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ORGANIC SPECTROSCOPY

Read all about Organic Spectroscopy on ORGANIC SPECTROSCOPY INTERNATIONAL 

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DR ANTHONY MELVIN CRASTO Ph.D

DR ANTHONY MELVIN CRASTO Ph.D

DR ANTHONY MELVIN CRASTO, Born in Mumbai in 1964 and graduated from Mumbai University, Completed his Ph.D from ICT, 1991,Matunga, Mumbai, India, in Organic Chemistry, The thesis topic was Synthesis of Novel Pyrethroid Analogues, Currently he is working with GLENMARK PHARMACEUTICALS LTD, Research Centre as Principal Scientist, Process Research (bulk actives) at Mahape, Navi Mumbai, India. Total Industry exp 30 plus yrs, Prior to joining Glenmark, he has worked with major multinationals like Hoechst Marion Roussel, now Sanofi, Searle India Ltd, now RPG lifesciences, etc. He has worked with notable scientists like Dr K Nagarajan, Dr Ralph Stapel, Prof S Seshadri, Dr T.V. Radhakrishnan and Dr B. K. Kulkarni, etc, He did custom synthesis for major multinationals in his career like BASF, Novartis, Sanofi, etc., He has worked in Discovery, Natural products, Bulk drugs, Generics, Intermediates, Fine chemicals, Neutraceuticals, GMP, Scaleups, etc, he is now helping millions, has 9 million plus hits on Google on all Organic chemistry websites. His friends call him Open superstar worlddrugtracker. His New Drug Approvals, Green Chemistry International, All about drugs, Eurekamoments, Organic spectroscopy international, etc in organic chemistry are some most read blogs He has hands on experience in initiation and developing novel routes for drug molecules and implementation them on commercial scale over a 30 year tenure till date Dec 2017, Around 35 plus products in his career. He has good knowledge of IPM, GMP, Regulatory aspects, he has several International patents published worldwide . He has good proficiency in Technology transfer, Spectroscopy, Stereochemistry, Synthesis, Polymorphism etc., He suffered a paralytic stroke/ Acute Transverse mylitis in Dec 2007 and is 90 %Paralysed, He is bound to a wheelchair, this seems to have injected feul in him to help chemists all around the world, he is more active than before and is pushing boundaries, He has 9 million plus hits on Google, 2.5 lakh plus connections on all networking sites, 50 Lakh plus views on dozen plus blogs, He makes himself available to all, contact him on +91 9323115463, email amcrasto@gmail.com, Twitter, @amcrasto , He lives and will die for his family, 90% paralysis cannot kill his soul., Notably he has 19 lakh plus views on New Drug Approvals Blog in 216 countries......https://newdrugapprovals.wordpress.com/ , He appreciates the help he gets from one and all, Friends, Family, Glenmark, Readers, Wellwishers, Doctors, Drug authorities, His Contacts, Physiotherapist, etc

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FDA approves new treatment Victoza (liraglutide) for pediatric patients with type 2 diabetes


The U.S. Food and Drug Administration today approved Victoza (liraglutide) injection for treatment of pediatric patients 10 years or older with type 2 diabetes. Victoza is the first non-insulin drug approved to treat type 2 diabetes in pediatric patients since metformin was approved for pediatric use in 2000. Victoza has been approved to treat adult patients with type 2 diabetes since 2010.

“The FDA encourages drugs to be made available to the widest number of patients possible when there is evidence of safety and efficacy,” said Lisa Yanoff, M.D, acting director of the Division of Metabolism and Endocrinology Products in the FDA’s Center for Drug Evaluation and Research. “Victoza has now been shown to improve blood sugar control in pediatric patients with type 2 diabetes. The expanded indication provides an additional treatment option at a time when

June 17, 2019

The U.S. Food and Drug Administration today approved Victoza (liraglutide) injection for treatment of pediatric patients 10 years or older with type 2 diabetes. Victoza is the first non-insulin drug approved to treat type 2 diabetes in pediatric patients since metformin was approved for pediatric use in 2000. Victoza has been approved to treat adult patients with type 2 diabetes since 2010.

“The FDA encourages drugs to be made available to the widest number of patients possible when there is evidence of safety and efficacy,” said Lisa Yanoff, M.D, acting director of the Division of Metabolism and Endocrinology Products in the FDA’s Center for Drug Evaluation and Research. “Victoza has now been shown to improve blood sugar control in pediatric patients with type 2 diabetes. The expanded indication provides an additional treatment option at a time when an increasing number of children are being diagnosed with this disease.”

Type 2 diabetes is the most common form of diabetes, occurring when the pancreas cannot make enough insulin to keep blood sugar at normal levels. Although type 2 diabetes primarily occurs in patients over the age of 45, the prevalence rate among younger patients has been rising dramatically over the past couple of decades. The Diabetes Report Card published by the U.S. Centers for Disease Control and Prevention estimates that more than 5,000 new cases of type 2 diabetes are diagnosed each year among U.S. youth younger than age 20.

Victoza improves blood sugar levels by creating the same effects in the body as the glucagon-like peptide (GLP-1) receptor protein in the pancreas. GLP-1 is often found in insufficient levels in type 2 diabetes patients. Like GLP-1, Victoza slows digestion, prevents the liver from making too much glucose (a simple sugar), and helps the pancreas produce more insulin when needed. As noted on the label, Victoza is not a substitute for insulin and is not indicated for patients with type 1 diabetes or those with diabetic ketoacidosis, a condition associated with diabetes where the body breaks down fat too quickly because there is inadequate insulin or none at all. Victoza is also indicated to reduce the risk of major adverse cardiovascular events in adults with type 2 diabetes and established cardiovascular disease; however, its effect on major adverse cardiovascular events in pediatrics was not studied and it is not indicated for this use in children.

The efficacy and safety of Victoza for reducing blood sugar in patients with type 2 diabetes was studied in several placebo-controlled trials in adults and one placebo-controlled trial with 134 pediatric patients 10 years and older for more than 26 weeks. Approximately 64% of patients in the pediatric study had a reduction in their hemoglobin A1c (HbA1c) below 7% while on Victoza, compared to only 37% who achieved these results with the placebo. HbA1c is a blood test that is routinely performed to evaluate how well a patient’s diabetes is controlled, and a lower number indicates better control of the disease. These results occurred regardless of whether the patient also took insulin at the same time. Adult patients who took Victoza with insulin or other drugs that increase the amount of insulin the body makes (e.g., sulfonylurea) may have an increased risk of hypoglycemia (low blood sugar). Meanwhile, pediatric patients 10 years and older taking Victoza had a higher risk of hypoglycemia regardless of whether they took other therapies for diabetes.

The prescribing information for Victoza includes a Boxed Warning to advise health care professionals and patients about the increased risk of thyroid C-cell tumors. For this reason, patients who have had, or have family members who have ever had medullary thyroid carcinoma (MTC) should not use Victoza, nor should patients who have an endocrine system condition called multiple endocrine neoplasia syndrome type 2 (MEN 2). In addition, people who have a prior serious hypersensitivity reaction to Victoza or any of the product components should not use Victoza. Victoza also carries warnings about pancreatitis, Victoza pen sharing, hypoglycemia when used in conjunction with certain other drugs known to cause hypoglycemia including insulin and sulfonylurea, renal impairment or kidney failure, hypersensitivity and acute gallbladder disease. The most common side effects are nausea, diarrhea, vomiting, decreased appetite, indigestion and constipation.

The FDA granted this application Priority Review. The approval of Victoza was granted to Novo Nordisk.

https://www.fda.gov/news-events/press-announcements/fda-approves-new-treatment-pediatric-patients-type-2-diabetes?utm_campaign=061719_PR_FDA%20approves%20new%20treatment%20for%20pediatric%20patients%20with%20type%202%20diabetes&utm_medium=email&utm_source=Eloqua

//////Victoza, liraglutide, FDA 2019, Priority Review, Novo Nordisk, DIABETES

VX-445, Elexacaftor, エレクサカフトル


Elexacaftor.png

str1

VX-445, Elexacaftor, エレクサカフトル

597.658 g/mol, C26H34F3N7O4S

3-Pyridinecarboxamide, N-((1,3-dimethyl-1H-pyrazol-4-yl)sulfonyl)-6-(3-(3,3,3-trifluoro-2,2-dimethylpropoxy)-1H-pyrazol-1-yl)-2-((4S)-2,2,4-trimethyl-1-pyrrolidinyl)-

N-[(1,3-Dimethyl-1H-pyrazol-4-yl)sulfonyl]-6-[3-(3,3,3-trifluoro-2,2-dimethylpropoxy)-1H-pyrazol-1-yl]-2-[(4S)-2,2,4-trimethyl-1-pyrrolidinyl]-3-pyridinecarboxamide

3-Pyridinecarboxamide, N-((1,3-dimethyl-1H-pyrazol-4-yl)sulfonyl)-6-(3-(3,3,3-trifluoro-2,2-dimethylpropoxy)-1H-pyrazol-1-yl)-2-((4S)-2,2,4-trimethyl-1-pyrrolidinyl)-

UNII-RRN67GMB0V

RRN67GMB0V

VX-445

WHO 11180

Cas 2216712-66-0

WHO 11180

Treatment of cystic fibrosis, CFTR modulator

Elexacaftor is under investigation in clinical trial NCT03525548 (A Study of VX-445 Combination Therapy in CF Subjects Homozygous for F508del (F/F)).

Cystic fibrosis transmembrane conductance regulator (CFTR) corrector designed to restore Phe508del CFTR protein function in patients with cystic fibrosis when administered with tezacaftor and ivacaftor.

VX-445 (elexacaftor), tezacaftor, and ivacaftor triple-drug combo

Vertex Pharmaceuticals (NASDAQ: VRTX) already claims a virtual monopoly in treating the underlying cause of cystic fibrosis (CF). The biotech’s current three CF drugs should generate combined sales of close to $3.5 billion this year. Another blockbuster is likely to join those three drugs on the market in 2020 — Vertex’s triple-drug CF combo featuring VX-445 (elexacaftor), tezacaftor, and ivacaftor.

EvaluatePharma projects that this triple-drug combo will rake in close to $4.3 billion by 2024. The market researcher pegs the net present value of the drug at nearly $20 billion, making it the most valuable pipeline asset in the biopharmaceutical industry right now.

PATENT

WO 2018107100

https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2018107100&tab=PCTDESCRIPTION&queryString=novozymes&recNum=152&maxRec=27502

Also disclosed herein is Compound 1:

[0013] N-(1,3-dimethylpyrazol-4-yl)sulfonyl-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]-2-[(4S)-2,2,4-trimethylpyrrolidin-1-yl]pyridine-3-carboxamide.

Synthesis of Compound 1

[00256] Part A: Synthesis of (4S)-2,2,4-trimethylpyrrolidine hydrochloride

[00257] Step 1: methyl-2,4-dimethyl-4-nitro-pentanoate

[00258] Tetrahydrofuran (THF, 4.5 L) was added to a 20 L glass reactor and stirred under N2 at room temperature.2-Nitropropane (1.5 kg, 16.83 mol) and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) (1.282 kg, 8.42 mol) were then charged to the reactor, and the jacket temperature was increased to 50 °C. Once the reactor contents were close to 50 °C, methyl methacrylate (1.854 kg, 18.52 mol) was added slowly over 100 minutes. The reaction temperature was maintained at or close to 50 °C for 21 hours. The reaction mixture was concentrated in vacuo then transferred back to the reactor and diluted with methyl tert-butyl ether (MTBE) (14 L).2 M HCl (7.5 L) was added, and this mixture was stirred for 5 minutes then allowed to settle. Two clear layers were visible– a lower yellow aqueous phase and an upper green organic phase. The aqueous layer was removed, and the organic layer was stirred again with 2 M HCl (3 L). After separation, the HCl washes were recombined and stirred with MTBE (3 L) for 5 minutes. The aqueous layer was removed, and all of the organic layers were combined in the reactor and stirred with water (3 L) for 5 minutes. After separation, the organic layers were concentrated in vacuo to afford a cloudy green oil. Crude product was treated with MgSO4 and filtered to afford methyl-2,4-dimethyl-4-nitro-pentanoate as a clear green oil (3.16 kg, 99% yield).

[00259] 1H NMR (400 MHz, Chloroform-d) δ 3.68 (s, 3H), 2.56– 2.35 (m, 2H), 2.11 – 2.00 (m, 1H), 1.57 (s, 3H), 1.55 (s, 3H), 1.19 (d, J = 6.8 Hz, 3H).

[00260] Step 2: Synthesis of methyl (2S)-2,4-dimethyl-4-nitro-pentanoate

[00261] A reactor was charged with purified water (2090 L; 10 vol) and then potassium phosphate monobasic (27 kg, 198.4 moles; 13 g/L for water charge). The pH of the reactor contents was adjusted to pH 6.5 (± 0.2) with 20% (w/v) potassium carbonate solution. The reactor was charged with racemic methyl-2,4-dimethyl-4-nitro-pentanoate (209 kg; 1104.6 moles), and Palatase 20000L lipase (13 L, 15.8 kg; 0.06 vol).

[00262] The reaction mixture was adjusted to 32 ± 2 °C and stirred for 15-21 hours, and pH 6.5 was maintained using a pH stat with the automatic addition of 20% potassium carbonate solution. When the racemic starting material was converted to >98% ee of the S-enantiomer, as determined by chiral GC, external heating was switched off. The reactor was then charged with MTBE (35 L; 5 vol), and the aqueous layer was extracted with MTBE (3 times, 400-1000L). The combined organic extracts were washed with aqueous Na2CO3 (4 times, 522 L, 18 % w/w 2.5 vol), water (523 L; 2.5 vol), and 10% aqueous NaCl (314 L, 1.5 vol). The organic layer was concentrated in vacuo to afford methyl (2S)-2,4-dimethyl-4-nitro-pentanoate as a mobile yellow oil (>98% ee, 94.4 kg; 45 % yield).

[00263] Step 3: Synthesis of (3S)-3,5,5-trimethylpyrrolidin-2-one

[00264] A 20 L reactor was purged with N2. The vessel was charged sequentially with DI water-rinsed, damp Raney® Ni (2800 grade, 250 g), methyl (2S)-2,4-dimethyl-4-nitro-pentanoate (1741g, 9.2 mol), and ethanol (13.9 L, 8 vol). The reaction was stirred at 900 rpm, and the reactor was flushed with H2 and maintained at ~2.5 bar. The reaction mixture was then warmed to 60 °C for 5 hours. The reaction mixture was cooled and filtered to remove Raney nickel, and the solid cake was rinsed with ethanol (3.5 L, 2 vol). The ethanolic solution of the product was combined with a second equal sized batch and concentrated in vacuo to reduce to a minimum volume of ethanol (~1.5 volumes). Heptane (2.5 L) was added, and the suspension was concentrated again to ~1.5 volumes. This was repeated 3 times; the resulting suspension was cooled to 0-5 °C, filtered under suction, and washed with heptane (2.5 L). The product was dried under vacuum for 20 minutes then transferred to drying trays and dried in a vacuum oven at 40 °C overnight to afford (3S)-3,5,5-trimethylpyrrolidin-2-one as a white crystalline solid (2.042 kg, 16.1 mol, 87 %).1H NMR (400 MHz, Chloroform-d) δ 6.39 (s, 1H), 2.62 (ddq, J = 9.9, 8.6, 7.1 Hz, 1H), 2.17 (dd, J = 12.4, 8.6 Hz, 1H), 1.56 (dd, J = 12.5, 9.9 Hz, 1H), 1.31 (s, 3H), 1.25 (s, 3H), 1.20 (d, J = 7.1 Hz, 3H).

[00265] Step 4: Synthesis of (4S)-2,2,4-trimethylpyrrolidine hydrochloride

[00266] A glass lined 120 L reactor was charged with lithium aluminum hydride pellets (2.5 kg, 66 mol) and dry THF (60 L) and warmed to 30 °C. The resulting suspension was charged with (S)-3,5,5-trimethylpyrrolidin-2-one (7.0 kg, 54 mol) in THF (25 L) over 2 hours while maintaining the reaction temperature at 30 to 40 °C. After complete addition, the reaction temperature was increased to 60 – 63 °C and maintained overnight. The reaction mixture was cooled to 22 °C, then cautiously quenched with the addition of ethyl acetate (EtOAc) (1.0 L, 10 moles), followed by a mixture of THF (3.4 L) and water (2.5 kg, 2.0 eq), and then a mixture of water (1.75 kg) with 50 % aqueous sodium hydroxide (750 g, 2 equiv water with 1.4 equiv sodium hydroxide relative to aluminum), followed by 7.5 L water. After the addition was complete, the reaction mixture was cooled to room temperature, and the solid was removed by filtration and washed with THF (3 x 25 L). The filtrate and washings were combined and treated with 5.0 L (58 moles) of aqueous 37% HCl (1.05 equiv.) while maintaining the temperature below 30°C. The resultant solution was concentrated by

vacuum distillation to a slurry. Isopropanol (8 L) was added and the solution was concentrated to near dryness by vacuum distillation. Isopropanol (4 L) was added, and the product was slurried by warming to about 50 °C. MTBE (6 L) was added, and the slurry was cooled to 2-5 °C. The product was collected by filtration and rinsed with 12 L MTBE and dried in a vacuum oven (55 °C/300 torr/N2 bleed) to afford (4S)-2,2,4-trimethylpyrrolidine•HCl as a white, crystalline solid (6.21 kg, 75% yield). 1H NMR (400 MHz, DMSO-d6) δ 9.34 (br d, 2H), 3.33 (dd, J = 11.4, 8.4 Hz, 1H), 2.75 (dd, J = 11.4, 8.6 Hz, 1H), 2.50– 2.39 (m, 1H), 1.97 (dd, J = 12.7, 7.7 Hz, 1H), 1.42 (s, 3H), 1.38 (dd, J = 12.8, 10.1 Hz, 1H), 1.31 (s, 3H), 1.05 (d, J = 6.6 Hz, 3H).

[00267] Part B: Preparation of N-(1,3-dimethylpyrazol-4-yl)sulfonyl-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]-2-[(4S)-2,2,4-trimethylpyrrolidin-1-yl]pyridine-3-carboxamide (Compound 1)

[00268] Preparation of starting materials:

[00269] 3,3,3-Trifluoro-2,2-dimethyl-propan-1-ol

[00270] A 1 L 3 neck round bottom flask was fitted with a mechanical stirrer, a cooling bath, an addition funnel, and a J-Kem temperature probe. The vessel was charged with lithium aluminum hydride (LAH) pellets (6.3 g, 0.1665 mol) under a nitrogen atmosphere. The vessel was then charged with tetrahydrofuran (200 mL) under a nitrogen atmosphere. The mixture was allowed to stir at room temperature for 0.5 hours to allow the pellets to dissolve. The cooling bath was then charged with crushed ice in water and the reaction temperature was lowered to 0 oC. The addition funnel was charged with a solution of 3,3,3-trifluoro-2,2-dimethyl-propanoic acid (20 g, 0.1281 mol) in tetrahydrofuran (60 mL) and the clear pale yellow solution was added drop wise over 1 hour. After the addition was complete the mixture was allowed to slowly warm to room temperature and stirring was continued for 24 hours. The suspension was cooled to 0 oC with a crushed ice-water in the cooling bath and then quenched by the very slow and drop wise addition of water (6.3 ml), followed by sodium hydroxide solution (15 weight %; 6.3 mL) and then finally with water (18.9 mL). The reaction temperature of the resulting white suspension was recorded at 5 oC. The suspension was stirred at ~5 oC for 30 minutes and then filtered through a 20 mm layer of Celite. The filter cake was washed with tetrahydrofuran (2 x 100 mL). The filtrate was dried over sodium sulfate (150 g) and then filtered. The filtrate was concentrated under reduced pressure to provide a clear colorless oil (15 g) containing a mixture of the product 3,3,3-trifluoro-2,2-dimethyl-propan-1-ol in THF (73 % weight of product ~10.95g, and 27 wt.% THF as determined by 1H-NMR). The distillate from the rotary evaporation was distilled at atmospheric pressure using a 30 cm Vigreux column to provide 8.75 g of a residue containing 60 % weight of THF and 40 % weight of product (~3.5 g). The estimated total amount of product is 14.45 g (79% yield).1H NMR (400 MHz, DMSO-d6) δ 4.99 (t, J = 5.7 Hz, 1H), 3.38 (dd, J = 5.8, 0.9 Hz, 2H), 1.04 (d, J = 0.9 Hz, 6H).

[00271] tert-Butyl 3-oxo-2,3-dihydro-1H-pyrazole-1-carboxylate

[00272] A 50L Syrris controlled reactor was started and jacket set to 20 °C, stirring at 150 rpm, reflux condenser (10 °C) and nitrogen purge. MeOH (2.860 L) and methyl (E)-3-methoxyprop-2-enoate (2.643 kg, 22.76 mol) were added and the reactor was capped. The reaction was heated to an internal temperature of 40 °C and the system was set to hold jacket temp at 40 °C. Hydrazine hydrate (1300 g of 55 %w/w, 22.31 mol) was added portion wise via addition funnel over 30 min. The reaction was heated to 60 ^C for 1 h. The reaction mixture was cooled to 20 ^C and triethyamine (2.483 kg, 3.420 L, 24.54 mol) was added portion wise (exothermic), maintaining reaction temp <30 °C.

A solution of Boc anhydride (di-tert-butyl dicarbonate) (4.967 kg, 5.228 L, 22.76 mol) in MeOH (2.860 L) was added portion wise maintaining temperature <45 °C. The reaction mixture was stirred at 20 ^C for 16 h. The reaction solution was partially concentrated to remove MeOH, resulting in a clear light amber oil. The resulting oil was transferred to the 50L reactor, stirred and added water (7.150 L) and heptane (7.150 L). The additions caused a small amount of the product to precipitate. The aqueous layer was drained into a clean container and the interface and heptane layer were filtered to separate the solid (product). The aqueous layer was transferred back to the reactor, and the collected solid was placed back into the reactor and mixed with the aqueous layer. A dropping funnel was added to the reactor and loaded with acetic acid (1.474 kg, 1.396 L, 24.54 mol), then began dropwise addition of acid. The jacket was set to 0 °C to absorb the quench exotherm. After addition (pH=5), the reaction mixture was stirred for 1 h. The solid was collected by filtration and washed with water (7.150 L), and washed a second time with water (3.575 L) and pulled dry. The crystalline solid was scooped out of the filter into a 20L rotovap bulb and heptane (7.150 L) was added. The mixture was slurried at 45 °C for 30 mins, and then distilled off 1-2 volumes of solvent. The slurry in the rotovap flask was filtered and the solids washed with heptane (3.575 L) and pulled dry. The solid was further dried in vacuo (50 °C , 15 mbar) to give tert-butyl 5-oxo-1H-pyrazole-2-carboxylate (2921 g, 71%) as coarse, crystalline solid.1H NMR (400 MHz, DMSO-d6) δ 10.95 (s, 1H), 7.98 (d, J = 2.9 Hz, 1H), 5.90 (d, J = 2.9 Hz, 1H), 1.54 (s, 9H).

[00273] Step A: tert-Butyl 3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazole-1-carboxylate

[00274] A mixture of 3,3,3-trifluoro-2,2-dimethyl-propan-1-ol (10 g, 70.36 mmol) and tert-butyl 3-hydroxypyrazole-1-carboxylate (12.96 g, 70.36 mmol) in toluene (130 mL) was treated with triphenyl phosphine (20.30 g, 77.40 mmol) followed by isopropyl N-isopropoxycarbonyliminocarbamate (14.99 mL, 77.40 mmol) and the mixture was stirred at 110 °C for 16 hours. The yellow solution was concentrated under reduced

pressure, diluted with heptane (100mL) and the precipitated triphenylphosphine oxide was removed by filtration and washed with heptane/toluene 4:1 (100mL). The yellow filtrate was evaporated and the residue purified by silica gel chromatography with a linear gradient of ethyl acetate in hexane (0-40%) to give tert-butyl 3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazole-1-carboxylate (12.3 g, 57%) as an off white solid. ESI-MS m/z calc.308.13477, found 309.0 (M+1) +; Retention time: 1.84 minutes.1H NMR (400 MHz, DMSO-d6) δ 8.10 (d, J = 3.0 Hz, 1H), 6.15 (d, J = 3.0 Hz, 1H), 4.18 (s, 2H), 1.55 (s, 9H), 1.21 (s, 6H).

[00275] Step B: 3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)-1H-pyrazole

[00276] tert-Butyl 3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazole-1-carboxylate (13.5 g, 43.79 mmol) was treated with 4 M hydrogen chloride in dioxane (54.75 mL, 219.0 mmol) and the mixture was stirred at 45 °C for 1 hour. The reaction mixture was evaporated to dryness and the residue was extracted with 1 M aqueous NaOH (100ml) and methyl tert-butyl ether (100ml), washed with brine (50ml) and extracted with methyl tert-butyl ether (50ml). The combined organic phases were dried, filtered and evaporated to give 3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)-1H-pyrazole (9.0 g, 96%) as an off white waxy solid. ESI-MS m/z calc.208.08235, found 209.0 (M+1) +;

Retention time: 1.22 minutes.1H NMR (400 MHz, DMSO-d6) δ 11.91 (s, 1H), 7.52 (d, J = 2.2 Hz, 1H), 5.69 (t, J = 2.3 Hz, 1H), 4.06 (s, 2H), 1.19 (s, 6H).

[00277] Step C: tert-Butyl 2,6-dichloropyridine-3-carboxylate

[00278] A solution of 2,6-dichloropyridine-3-carboxylic acid (10 g, 52.08 mmol) in THF (210 mL) was treated successively with di-tert-butyl dicarbonate (17 g, 77.89 mmol) and 4-(dimethylamino)pyridine (3.2 g, 26.19 mmol) and left to stir overnight at room temperature. At this point, HCl 1N (400 mL) was added and the mixture was stirred vigorously for about 10 minutes. The product was extracted with ethyl acetate (2x300mL) and the combined organics layers were washed with water (300 mL) and brine (150 mL) and dried over sodium sulfate and concentrated under reduced pressure to give 12.94 g (96% yield) of tert-butyl 2,6-dichloropyridine-3-carboxylate as a colorless oil. ESI-MS m/z calc.247.01668, found 248.1 (M+1) +; Retention time: 2.27 minutes.1H NMR (300 MHz, CDCl3) ppm 1.60 (s, 9H), 7.30 (d, J=7.9 Hz, 1H), 8.05 (d, J=8.2 Hz, 1H).

[00279] Step D: tert-Butyl 2-chloro-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]pyridine-3-carboxylate

[00280] To a solution of tert-butyl 2,6-dichloropyridine-3-carboxylate (10.4 g, 41.9 mmol) and 3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)-1H-pyrazole (9.0 g, 41.93 mmol) in DMF (110 mL) were added potassium carbonate (7.53 g, 54.5 mmol) and 1,4-diazabicyclo[2.2.2]octane (706 mg, 6.29 mmol) and he mixture was stirred at room temperature for 16 hours. The cream suspension was cooled in a cold water bath and cold water (130 mL) was slowly added. The thick suspension was stirred at room temperature for 1 hour, filtered and washed with plenty of water to give tert-butyl 2-chloro-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]pyridine-3-carboxylate (17.6 g, 99%) as an off white solid. ESI-MS m/z calc.419.12234, found 420.0 (M+1) +; Retention time: 2.36 minutes.1H NMR (400 MHz, DMSO-d6) δ 8.44 (d, J = 2.9 Hz, 1H), 8.31 (d, J = 8.4 Hz, 1H), 7.76 (d, J = 8.4 Hz, 1H), 6.26 (d, J = 2.9 Hz, 1H), 4.27 (s, 2H), 1.57 (s, 9H), 1.24 (s, 6H).

[00281] Step E: 2-chloro-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]pyridine-3-carboxylic acid

[00282] tert-butyl 2-chloro-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]pyridine-3-carboxylate (17.6 g, 40.25 mmol) was suspended in isopropanol (85 mL) treated with hydrochloric acid (34 mL of 6 M, 201 mmol) and heated to reflux for 3 hours (went almost complete into solution at reflux and started to precipitate again). The suspension was diluted with water (51 mL) at reflux and left to cool to room

temperature under stirring for 2.5 h. The solid was collected by filtration, washed with isopropanol/water 1:1 (50mL), plenty of water and dried in a drying cabinet under vacuum at 45-50 °C with a nitrogen bleed overnight to give 2-chloro-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]pyridine-3-carboxylic acid (13.7 g, 91%) as an off white solid. ESI-MS m/z calc.363.05975, found 364.0 (M+1) +; Retention time: 1.79 minutes. 1H NMR (400 MHz, DMSO-d6) δ 13.61 (s, 1H), 8.44 (d, J = 2.9 Hz, 1H), 8.39 (d, J = 8.4 Hz, 1H), 7.77 (d, J = 8.4 Hz, 1H), 6.25 (d, J = 2.9 Hz, 1H), 4.28 (s, 2H), 1.24 (s, 6H).

[00283] Step F: 2-Chloro-N-(1,3-dimethylpyrazol-4-yl)sulfonyl-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]pyridine-3-carboxamide

[00284] 2-Chloro-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]pyridine-3-carboxylic acid (100 mg, 0.2667 mmol) and CDI (512 mg, 3.158 mmol) were combined in THF (582.0 µL) and the mixture was stirred at room temperature. Meanwhile, 1,3-dimethylpyrazole-4-sulfonyl chloride (62 mg, 0.3185 mmol) was combined with ammonia (in methanol) in a separate vial, instantly forming a white solid. After stirring for an additional 20 min, the volatiles were removed by evaporation, and 1 mL of dichloromethane was added to the solid residue, and was also evaporated. DBU (100 µL, 0.6687 mmol) was then added and the mixture stirred at 60 °C for 5 minutes, followed by addition of THF (1 mL) which was subsequently evaporated. The contents of the vial containing the CDI activated carboxylic acid in THF were then added to the vial containing the newly formed sulfonamide and DBU, and the reaction mixture was stirred for 4 hours at room temperature. The reaction mixture was diluted with 10 mL of ethyl acetate, and washed with 10 mL solution of citric acid (1 M). The aqueous layer was extracted with ethyl acetate (2x 10 mL) and the combined organics were washed with brine, dried over sodium sulfate, and concentrated to give the product as white solid (137 mg, 99%) that was used in the next step without further purification. ESI-MS m/z calc.520.09076, found 521.1 (M+1) +; Retention time: 0.68 minutes.

[00285] Step G: N-(1,3-dimethylpyrazol-4-yl)sulfonyl-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]-2-[(4S)-2,2,4-trimethylpyrrolidin-1-yl]pyridine-3-carboxamide

[00286] 2-Chloro-N-(1,3-dimethylpyrazol-4-yl)sulfonyl-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]pyridine-3-carboxamide (137 mg, 0.2630 mmol), (4S)-2,2,4-trimethylpyrrolidine (Hydrochloride salt) (118 mg, 0.7884 mmol) , and potassium carbonate (219 mg, 1.585 mmol) were combined in DMSO (685.0 µL) and the mixture was heated at 130 ^C for 16 hours. The reaction was cooled to room temperature, and 1 mL of water was added. After stirring for 15 minutes, the contents of the vial were allowed to settle, and the liquid portion was removed via pipet and the remaining solids were dissolved with 20 mL of ethyl acetate and were washed with 1 M citric acid (15 mL). The layers were separated and the aqueous layer was extracted two additional times with 15 mL of ethyl acetate. The organics were combined, washed with brine, dried over sodium sulfate and concentrated. The resulting solid was further purified by silica gel chromatography eluting with a gradient of methanol in dichloromethane (0-10%) to give N-(1,3-dimethylpyrazol-4-yl)sulfonyl-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]-2-[(4S)-2,2,4-trimethylpyrrolidin-1-yl]pyridine-3-carboxamide (72 mg, 41%) as a white solid. ESI-MS m/z calc.597.2345, found 598.3 (M+1) +; Retention time: 2.1 minutes.1H NMR (400 MHz, DMSO) δ 12.36 (s, 1H), 8.37 (s, 1H), 8.22 (d, J = 2.8 Hz, 1H), 7.74 (d, J = 8.2 Hz, 1H), 6.93 (d, J = 8.2 Hz, 1H), 6.17 (d, J = 2.8 Hz, 1H), 4.23 (s, 2H), 3.81 (s, 3H), 2.56 (d, J = 10.4 Hz, 1H), 2.41 (t, J = 8.7 Hz, 1H), 2.32 (s, 3H), 2.18 (dd, J = 12.4, 6.1 Hz, 1H), 1.87 (dd, J = 11.7, 5.5 Hz, 1H), 1.55 (d, J = 11.2 Hz, 6H), 1.42 (t, J = 12.0 Hz, 1H), 1.23 (s, 6H), 0.81 (d, J = 6.2 Hz, 3H).

[00287] Alternative Steps F and G:

[00288] Alternative Step F: 2-chloro-N-((1,3-dimethyl-1H-pyrazol-4-yl)sulfonyl)-6-(3-(3,3,3-trifluoro-2,2-dimethylpropoxy)-1H-pyrazol-1-yl)nicotinamide

[00289]

[00291] To a suspension of 2-chloro-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]pyridine-3-carboxylic acid (20.0 g, 53.89 mmol) in THF (78.40 mL) was added solid carbonyldiimidazole (approximately 10.49 g, 64.67 mmol) portion wise and the resulting solution was stirred at room temperature (slight exotherm from 18-21 °C was observed). After 1 h, solid 1,3-dimethylpyrazole-4-sulfonamide

(approximately 11.33 g, 64.67 mmol) was added, followed by DBU (approximately 9.845 g, 9.671 mL, 64.67 mmol) in two equal portions over 1 min (exotherm from 19 to 35 °C). The reaction mixture was stirred at room temperature for 16 h. The reaction mixture was diluted with ethyl acetate (118 mL) and then HCl (approximately 107.8 mL of 2 M, 215.6 mmol). The phases were separated and the aqueous phase was extracted

with ethyl aceate (78 mL). The combined organics were washed with water (39.2 mL), then brine (40 mL), dried over sodium sulfate and concentrated. The resulting foam was crystallized from a 1:1 isopropanol:heptane mixture (80 mL) to afford 2-chloro-N-((1,3-dimethyl-1H-pyrazol-4-yl)sulfonyl)-6-(3-(3,3,3-trifluoro-2,2-dimethylpropoxy)-1H-pyrazol-1-yl)nicotinamide (26.1 g, 93%) as a white solid. ESI-MS m/z calc.520.0, found 520.9 (M+1) +; Retention time: 1.83 minutes.

[00292] Alternative Step G: N-(1,3-dimethylpyrazol-4-yl)sulfonyl-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]-2-[(4S)-2,2,4-trimethylpyrrolidin-1-yl]pyridine-3-carboxamide

[00294] 2-chloro-N-(1,3-dimethylpyrazol-4-yl)sulfonyl-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]pyridine-3-carboxamide (20.0 g, 38.39 mmol), (4S)-2,2,4-trimethylpyrrolidine (Hydrochloride salt) (approximately 14.36 g, 95.98 mmol), and K2CO3 (approximately 26.54 g, 192.0 mmol) were combined in DMSO (80.00 mL) and 1,2-diethoxyethane (20.00 mL) in a 500-mL flask with reflux condenser. The reaction mixture was heated at 120 °C for 16 h then cooled to room temperature. The reaction was diluted with DCM (200.0 mL) and HCl (approximately 172.8 mL of 2 M, 345.5 mmol); aqueous pH ~1. The phases were separated, and the aqueous phase was extracted with DCM (100.0 mL). The organic phases were combined, washed with water (100.0 mL) (3 x), and dried (Na2SO4) to afford an amber solution. The solution was filtered through a DCM-packed silica gel bed (80 g; 4 g/g) and washed with 20% EtOAc/DCM (5 x 200 mL). The combined filtrate/washes were concentrated to afford 22.2 g of an off-white powder. The powder was slurried in MTBE (140 mL) for 30 min. The solid was collected by filtration (paper/sintered-glass) to afford 24 g after air-drying. The solid was transferred to a drying dish and vacuum-dried (40 °C/200 torr/N2 bleed) overnight to afford 20.70 g (90%) of a white powder. ESI-MS m/z calc.

597.2345, found 598.0 (M+1)+; Retention time: 2.18 minutes.

[00295] 1H NMR (400 MHz, Chloroform-d) δ 13.85 (s, 1H), 8.30 (d, J = 8.6 Hz, 1H), 8.23 (d, J = 2.8 Hz, 1H), 8.08 (s, 1H), 7.55 (d, J = 8.5 Hz, 1H), 5.98 (d, J = 2.8 Hz, 1H), 4.24 (s, 2H), 3.86 (s, 3H), 3.44 (dd, J = 10.3, 8.4 Hz, 1H), 3.09 (dd, J = 10.3, 7.8 Hz, 1H), 2.67– 2.52 (m, 1H), 2.47 (s, 3H), 2.12 (dd, J = 12.3, 7.8 Hz, 1H), 1.70 (dd, J = 12.4, 9.6 Hz, 1H), 1.37 (s, 3H), 1.33 (s, 3H), 1.27 (s, 6H), 1.20 (d, 3H).

[00296] Alternative Synthesis of 3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)-1H-pyrazole

Step 1: Preparation of 3,3,3-trifluoro-2,2-dimethylpropan-1-ol

A reactor was loaded with toluene (300 mL) and 3,3,3-trifluoro-2,2-dimethylpropanoic acid (30 g, 192.2 mmol), capped, purged under nitrogen. The reaction was set to control the internal temperature to 40 °C. A solution of Vitride (65% in toluene. approximately 119.6 g of 65 %w/w, 115.4 mL of 65 %w/w, 384.4 mmol) was set up for addition via syringe, and addition was begun at 40 °C, with the target addition temperature between 40 and 50 °C. The reaction was stirred at 40 °C for 90 min. The reaction was cooled to 10 °C then the remaining Vitride was quenched with slow addition of water (6 mL). A solution of 15 % aq NaOH (30 mL) was added in portions, and solids precipitated half way through the base addition. Water (60.00 mL) was added. The mixture was warmed to 30 °C and held for at least 15 mins. The mixture was then cooled to 20 °C. The

aqueous layer was removed. The organic layer was washed with water (60 mL x 3), and then washed with brine (60 mL). The washed organic layer was dried under Na2SO4, followed with MgSO4. The mix was filtered through Celite, and the cake washed with toluene (60.00 mL) and pulled dry. The product 3,3,3-trifluoro-2,2-dimethyl-propan-1-ol (22.5 g, 82%) was obtained as clear colorless solution.

Step 2: Preparation of 1-(tert-butyl) 4-ethyl 3-(3,3,3-trifluoro-2,2-dimethylpropoxy)-1H-pyrazole-1,4-dicarboxylate

A reactor was charged with 3,3,3-trifluoro-2,2-dimethylpropan-1-ol (17.48 g, 123.0 mmol) solution in toluene (250g), 1-(tert-butyl) 4-ethyl 3-hydroxy-1H-pyrazole-1,4-dicarboxylate (30.0 g, 117.1 mmol), and PPh3 (35.33 g, 134.7 mmol). The reaction was heated to 40 °C. DIAD (26.09 mL, 134.7 mmol) was weighed and placed into a syringe and added over 10 minutes while maintaining an internal temperature ranging between 40 and 50 °C. The reaction was then heated to 100 °C over 30 minutes. After holding at 100 °C for 30 minutes, the reaction was complete, and the mixture was cooled to 70 °C over 15 minutes. Heptane (180.0 mL) was added, and the jacket was cooled to 15 °C over 1 hour. (TPPO began crystallizing at ~35 °C). The mixture stirring at 15 °C was filtered (fast), the cake was washed with a pre-mixed solution of toluene (60 mL) and heptane (60 mL) and then pulled dry. The clear solution was concentrated to a waxy solid (45 °C, vacuum, rotovap). Crude 1-(tert-butyl) 4-ethyl 3-(3,3,3-trifluoro-2,2-dimethylpropoxy)-1H-pyrazole-1,4-dicarboxylate (53.49g) was obtained as a waxy solid, (~120% of theoretical mass recovered).

Step 3: Preparation of 3-(3,3,3-trifluoro-2,2-dimethylpropoxy)-1H-pyrazole-4-carboxylic acid

A solution of 1-(tert-butyl) 4-ethyl 3-(3,3,3-trifluoro-2,2-dimethylpropoxy)-1H-pyrazole-1,4-dicarboxylate (50.0 g, 131 mmol) in 2-methyltetrahydrofuran (500 mL) was prepared in a reactor and stirred at 40 °C. Portions of KOt-Bu (80.85 g, 720.5 mmol) were then added over 30 minutes. Addition was exothermic. After 2053.49g UPLC-MS showed complete removal of the Boc group, so water (3.53 g, 3.53 mL, 196 mmol) was added drop-wise addition via syringe over 20 min to keep the reaction temperature between 40-50 °C. The mixture was then stirred for 17 hours to complete the reaction. The mixture was then cooled to 20 °C and water (400 mL) was added. The stirring was stopped and the layers were separated. The desired product in the aqueous layer was returned to the reactor and the organic layer was discarded. The aqueous layer was washed with 2-Me-THF (200 mL). Isopropanol (50. mL) was added followed by dropwise addition of aqueous HCl (131 mL of 6.0 M, 786.0 mmol) to adjust the pH to ❤ while maintaining the temperature below 30 °C. The resulting solid was then isolated by filtration and the filter cake washer with water (100 mL) then pulled dry until a sticky cake was obtained. The solids were then dried under vacuum at 55 °C to afford 3-(3,3,3-trifluoro-2,2-dimethylpropoxy)-1H-pyrazole-4-carboxylic acid (23.25 g) as an off-white fine solid.

[00297] Step 4: Preparation of 3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)-1H-pyrazole

3-(3,3,3-trifluoro-2,2-dimethylpropoxy)-1H-pyrazole-4-carboxylic acid (1.0 equiv) was added to a reactor followed by DMF (6.0 vol, 2.6 wt equiv). The mixture was stirred at 18– 22 °C. DBU (0.2 equiv.) was charged to the reaction mixture at a rate of approximately 45 mL/min. The reaction temperature was then raised to 98– 102 °C over 45 minutes. The reaction mixture was stirred at 98– 102 °C for no less than 10 h. The reaction mixture was then cooled to -2°C to 2 °C over approximately 1 hour and was used without isolation to make ethyl 2-chloro-6-(3-(3,3,3-trifluoro-2,2-dimethylpropoxy)-1H-pyrazol-1-yl)nicotinate.

[00298] Alternate procedure for the preparation of 2-chloro-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]pyridine-3-carboxylic acid

[00299] Step 1. Ethyl 2-chloro-6-(3-(3,3,3-trifluoro-2,2-dimethylpropoxy)-1H-pyrazol-1-yl)nicotinate

[00300] A solution of ethyl 2,6-dichloronicotinate (256 g, 1.16 mol) and 3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)-1H-pyrazole (242 g, 1.16 mol) in DMF (1.53 L) was treated with potassium carbonate (209 g, 1.51 mol) and DABCO (19.6 g, 174 mmol). The resultant suspension was stirred allowed to exotherm from 14 to 25 °C and then maintained at 20– 25 °C with external cooling for 3 days. The suspension was cooled to below 10 °C when water (2.0 L) was added in a thin stream while maintaining the temperature below 25 °C. After the addition was complete, the suspension was stirred for an additional 1 h. The solid was collected by filtration (sintered-glass/polypad) and the filter-cake was washed with water (2 x 500-mL) and dried with suction for 2 h to afford water-damp ethyl 2-chloro-6-(3-(3,3,3-trifluoro-2,2-dimethylpropoxy)-1H-pyrazol-1-yl)nicotinate (512 g; 113% yield) as white powder which was used without further steps in the subsequent reaction.

[00301] Step 2.2-chloro-6-(3-(3,3,3-trifluoro-2,2-dimethylpropoxy)-1h-pyrazol-1-yl)nicotinic acid

[00302] The water-damp ethyl 2-chloro-6-(3-(3,3,3-trifluoro-2,2-dimethylpropoxy)-1H-pyrazol-1-yl)nicotinate (455 g, 1.16 mol; assumed 100% yield from previous step) in EtOH (1.14 L) and THF (455 mL) was stirred at ambient temperature (17 °C) when 1 M NaOH (1.16 L, 1.16 mol) was added. The reaction mixture exothermed to 30 °C and was further warmed at 40 °C for 2 h. The solution was quenched with 1 M HCl (1.39 L, 1.39 mol) which resulted in an immediate precipitation which became thicker as the acid was added. The creamy suspension was allowed to cool to room temperature and was stirred overnight. The solid was collected by filtration (sintered-glass/poly pad). The filter-cake was washed with water (2 x 500-mL). The filter-cake was dried by suction for 1 h but remained wet. The damp solid was transferred to a 10-L Buchi flask for further drying (50 °C/20 torr), but was not effective. Further effort to dry by chasing with i-PrOH was also ineffective. Successful drying was accomplished after the damp solid was backfilled with i-PrOAc (3 L), the suspension was heated at 60 °C (homogenization), and re-concentrated to dryness (50 °C/20 torr) to afford dry 2-chloro-6-(3-(3,3,3-trifluoro-2,2-dimethylpropoxy)-1h-pyrazol-1-yl)nicotinic acid (408 g; 97% yield for two steps) as a fine, white powder. The product was further dried in a vacuum oven (50 °C/10 torr/N2 bleed) for 2 h but marginal weight loss was observed. 1H NMR (400 MHz, DMSO-d6) δ 13.64 (s, 1H), 8.49– 8.36 (m, 2H), 7.77 (d, J = 8.4 Hz, 1H), 6.26 (d, J = 2.8 Hz, 1H), 4.28 (s, 2H), 1.24 (s, 6H).19F NMR (376 MHz, DMSO-d6) δ -75.2. KF analysis: 0.04% water.

2. Preparation of Form A of Compound 1

[00303] The crystalline Form A of Compound 1 was obtained as a result of the following synthesis. Combined 2-chloro-N-(1,3-dimethylpyrazol-4-yl)sulfonyl-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]pyridine-3-carboxamide(108 g, 207.3 mmol), (4S)-2,2,4-trimethylpyrrolidine (Hydrochloride salt) (77.55 g, 518.2 mmol), was combined with K2CO3 (143.2 g, 1.036 mol) in DMSO (432.0 mL) and 1,2-

diethoxyethane (108.0 mL) in a 1-L RB flask with a reflux condenser. The resulting suspension was heated at 120°C and was stirred at temperature overnight. Then the reaction was diluted with DCM (1.080 L) and HCl (933.0 mL of 2 M, 1.866 mol) was slowly added. The liquid phases were separated, and the aqueous phase was extracted with DCM (540.0 mL).The organic phases were combined, washed with water (540.0 mL) (3 x), then dried with (Na2SO4) to afford an amber solution. Silica gel (25 g) was added and then the drying agent/silica gel was filtered off. The filter-bed was washed with DCM (3 x 50-mL). The organic phases were combined and concentrated (40 °C/40 torr) to afford crude N-(1,3-dimethylpyrazol-4-yl)sulfonyl-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]-2-[(4S)-2,2,4-trimethylpyrrolidin-1-yl]pyridine-3-carboxamide (198.6 g, 160% theory) as an off-white solid. The solid was diluted with MTBE (750 mL), warmed at 60 °C (external temperature), and mixed to a homogenous suspension. The suspension was cooled to 30 °C with stirring and the solid was collected by filtration, air-dried, and vacuum-dried to afford Compound 1 (111.1 g; 90 %) as a fine, white powder.

[00304] The crystalline Form A of Compound 1 was also obtained through the following procedure. A suspension of Compound 1 (150.0 g, 228.1 mmol) in iPrOH (480 mL) and water (120 mL) was heated at 82 °C to obtain a solution. The solution was cooled with a J-Kem controller at a cooling rate of 10 °C/h. Once the temperature reached 74 °C, the solution was seeded with a sample of Compound 1 in crystalline Form A. Crystallization occurred immediately. The suspension was cooled to 20 °C. The solid was collected by filtration, washed with i-PrOH (2 x 75 mL), air-dried with suction, and vacuum-dried (55 °C/300 torr/N2 bleed) to afford Compound 1, Form A (103.3 g) as a white powder.. The sample was cooled to ~5 °C, let stir for 1 h, and then the solid was collected by filtration (sintered glass/paper). the filter-cake was washed with i-PrOH (75 mL) (2 x), air-dried with suction, air-dried in a drying dish (120.6 g mostly dried), vacuum-dried (55 °C/300 torr/N2 bleed) for 4 h, and then RT overnight. Overnight drying afforded 118.3 g (87% yield) of a white powder.

PATENT

WO-2019113476

Example 1: Synthesis of (4S)-2,2,4-trimethylpyrrolidine hydrochloride

Step 1: methyl-2,4-dimethyl-4-nitro-pentanoate

[00110] Tetrahydrofuran (THF, 4.5 L) was added to a 20 L glass reactor and stirred under N2 at room temperature. 2-Nitropropane (1.5 kg, 16.83 mol) and 1,8-diazabicyclo[5.4.0]undec-7-ene (DBU) (1.282 kg, 8.42 mol) were then charged to the reactor, and the jacket temperature was increased to 50 °C. Once the reactor contents were close to 50 °C, methyl methacrylate (1.854 kg, 18.52 mol) was added slowly over 100 minutes. The reaction temperature was maintained at or close to 50 °C for 21 hours. The reaction mixture was concentrated in vacuo then transferred back to the reactor and diluted with methyl tert-butyl ether (MTBE) (14 L). 2 M HCl (7.5 L) was added, and this mixture was stirred for 5 minutes then allowed to settle. Two clear layers were visible– a lower yellow aqueous phase and an upper green organic phase. The aqueous layer was removed, and the organic layer was stirred again with 2 M HCl (3 L). After separation, the HCl washes were recombined and stirred with MTBE (3 L) for 5 minutes. The aqueous layer was removed, and all of the organic layers were combined in the reactor and stirred with water (3 L) for 5 minutes. After separation, the organic layers were concentrated in vacuo to afford a cloudy green oil. Crude product was treated with MgSO4 and filtered to afford methyl-2,4-dimethyl-4-nitro-pentanoate as a clear green oil (3.16 kg, 99% yield).

[00111] 1H NMR (400 MHz, Chloroform-d) δ 3.68 (s, 3H), 2.56– 2.35 (m, 2H), 2.11 – 2.00 (m, 1H), 1.57 (s, 3H), 1.55 (s, 3H), 1.19 (d, J = 6.8 Hz, 3H).

Step 2: Synthesis of methyl (2S)-2,4-dimethyl-4-nitro-pentanoate

[00112] A reactor was charged with purified water (2090 L; 10 vol) and then potassium phosphate monobasic (27 kg, 198.4 moles; 13 g/L for water charge). The pH of the reactor contents was adjusted to pH 6.5 (± 0.2) with 20% (w/v) potassium carbonate solution. The reactor was charged with racemic methyl-2,4-dimethyl-4-nitro-pentanoate (209 kg; 1104.6 moles), and Palatase 20000L lipase (13 L, 15.8 kg; 0.06 vol).

[00113] The reaction mixture was adjusted to 32 ± 2 °C and stirred for 15-21 hours, and pH 6.5 was maintained using a pH stat with the automatic addition of 20% potassium carbonate solution. When the racemic starting material was converted to >98% ee of the S-enantiomer, as determined by chiral GC, external heating was switched off. The reactor was then charged with MTBE (35 L; 5 vol), and the aqueous layer was extracted with MTBE (3 times, 400-1000L). The combined organic extracts were washed with aqueous Na2CO3 (4 times, 522 L, 18 % w/w 2.5 vol), water (523 L; 2.5 vol), and 10% aqueous NaCl (314 L, 1.5 vol). The organic layer was concentrated in vacuo to afford methyl (2S)-2,4-dimethyl-4-nitro-pentanoate as a mobile yellow oil (>98% ee, 94.4 kg; 45 % yield).

Step 3: Synthesis of (3S)-3,5,5-trimethylpyrrolidin-2-one

[00114] A 20 L reactor was purged with N2. The vessel was charged sequentially with DI water-rinsed, damp Raney® Ni (2800 grade, 250 g), methyl (2S)-2,4-dimethyl-4-nitro-pentanoate (1741g, 9.2 mol), and ethanol (13.9 L, 8 vol). The reaction was stirred at 900 rpm, and the reactor was flushed with H2 and maintained at ~2.5 bar. The reaction mixture was then warmed to 60 °C for 5 hours. The reaction mixture was cooled and filtered to remove Raney nickel, and the solid cake was rinsed with ethanol (3.5 L, 2 vol). The ethanolic solution of the product was combined with a second equal sized batch and concentrated in vacuo to reduce to a minimum volume of ethanol (~1.5 volumes). Heptane (2.5 L) was added, and the suspension was concentrated again to ~1.5 volumes. This was repeated 3 times; the resulting suspension was cooled to 0-5 °C, filtered under suction, and washed with heptane (2.5 L). The product was dried under vacuum for 20 minutes then transferred to drying trays and dried in a vacuum oven at 40 °C overnight to afford (3S)-3,5,5-trimethylpyrrolidin-2-one as a white solid (2.042 kg, 16.1 mol, 87 %). 1H NMR (400 MHz, Chloroform-d) δ 6.39 (s, 1H), 2.62 (ddq, J = 9.9, 8.6, 7.1 Hz, 1H), 2.17 (dd, J = 12.4, 8.6 Hz, 1H), 1.56 (dd, J = 12.5, 9.9 Hz, 1H), 1.31 (s, 3H), 1.25 (s, 3H), 1.20 (d, J = 7.1 Hz, 3H).

Step 4: Synthesis of (4S)-2,2,4-trimethylpyrrolidine hydrochloride

[00115] A glass lined 120 L reactor was charged with lithium aluminum hydride pellets (2.5 kg, 66 mol) and dry THF (60 L) and warmed to 30 °C. The resulting suspension was charged with (S)-3,5,5-trimethylpyrrolidin-2-one (7.0 kg, 54 mol) in THF (25 L) over 2 hours while maintaining the reaction temperature at 30 to 40 °C. After complete addition, the reaction temperature was increased to 60 – 63 °C and maintained overnight. The reaction mixture was cooled to 22 °C, then cautiously quenched with the addition of ethyl acetate (EtOAc) (1.0 L, 10 moles), followed by a mixture of THF (3.4 L) and water (2.5 kg, 2.0 eq), and then a mixture of water (1.75 kg) with 50 % aqueous sodium hydroxide (750 g, 2 equiv water with 1.4 equiv sodium hydroxide relative to aluminum), followed by 7.5 L water. After the addition was complete, the reaction mixture was cooled to room temperature, and the solid was removed by filtration and washed with THF (3 x 25 L). The filtrate and washings were combined and treated with 5.0 L (58 moles) of aqueous 37% HCl (1.05 equiv.) while maintaining the temperature below 30°C. The resultant solution was concentrated by vacuum distillation to a slurry. Isopropanol (8 L) was added and the solution was concentrated to near dryness by vacuum distillation. Isopropanol (4 L) was added, and the product was slurried by warming to about 50 °C. MTBE (6 L) was added, and the slurry was cooled to 2-5 °C. The product was collected by filtration and rinsed with 12 L MTBE and dried in a vacuum oven (55 °C/300 torr/N2 bleed) to afford (4S)-2,2,4-trimethylpyrrolidine•HCl as a white solid (6.21 kg, 75% yield). 1H NMR (400 MHz, DMSO-d6) δ 9.34 (br d, 2H), 3.33 (dd, J = 11.4, 8.4 Hz, 1H), 2.75 (dd, J = 11.4, 8.6 Hz, 1H), 2.50– 2.39 (m, 1H), 1.97 (dd, J = 12.7, 7.7 Hz, 1H), 1.42 (s, 3H), 1.38 (dd, J = 12.8, 10.1 Hz, 1H), 1.31 (s, 3H), 1.05 (d, J = 6.6 Hz, 3H).

Example 2: Synthesis of 5,5-dimethyl-3-methylenepyrrolidin-2-one

Example 2A

[00116] 2,2,6,6-tetramethylpiperidin-4-one (50.00 g, 305.983 mmol, 1.000 equiv), tributylmethyl ammonium chloride (2.89 g, 3.0 mL, 9.179 mmol, 0.030 equiv), chloroform (63.92 g, 43.2 mL, 535.470 mmol, 1.750 equiv), and DCM

(dichloromethane) (100.0 mL, 2.00 vol) were charged to a 1000 mL three-neck round bottom flask equipped with an overhead stirrer. The reaction mixture was stirred at 300 rpm, and 50 wt% NaOH (195.81 g, 133.2 mL, 2,447.863 mmol, 8.000 equiv) was added dropwise (via addition funnel) over 1.5 h while maintaining the temperature below 25 °C with intermittent ice/acetone bath. The reaction mixture was stirred at 500 rpm for 18 h, and monitored by GC (3% unreacted piperidinone after 18 h). The suspension was diluted with DCM (100.0 mL, 2.00 vol) and H2O (300.0 mL, 6.00 vol), and the phases were separated. The aqueous phase was extracted with DCM (100.0 mL, 2.00 vol). The organic phases were combined and 3 M hydrochloric acid (16.73 g, 153.0 mL, 458.974 mmol, 1.500 equiv) was added. The mixture was stirred at 500 rpm for 2 h. The conversion was complete after approximately 1 h. The aqueous phase was saturated with NaCl, H2O (100.0 mL, 2.00 vol) was added to help reduce the emulsion, and the phases were separated. The aqueous phase was extracted with DCM (100.0 mL, 2.00 vol) twice. H2O (100.0 mL, 2.00 vol) was added to help with emulsion separation. The organic phases were combined, dried (MgSO4), and concentrated to afford 32.6 g (85%) of crude 5,5-dimethyl-3-methylenepyrrolidin-2-one (19) as a pale orange clumpy solid. The crude was recrystallized from hot (90°C) iPrOAc (71.7 mL, 2.2 vol. of crude), cooled to 80 °C, and ~50 mg of crystalline 5,5-dimethyl-3-methylenepyrrolidin-2-one (19) was added for seeding. Crystallization started at 77 °C, the mixture was slowly cooled to ambient temperature, and aged for 2 h. The solid was collected by filtration, washed with 50/50 iPrOAc/heptane (20.0 mL, 0.40 vol) twice, and dried overnight in the vacuum oven at 40 °C to afford the desired product (23.70 g, 189.345 mmol, 62% yield) as a white sand colored crystalline solid.

1H NMR (400 MHz, CDCl3, 7.26 ppm) δ 7.33 (bs, 1H), 5.96– 5.95 (m, 1H), 5.31-5.30 (m, 1H), 2.6 (t, J = 2.5 Hz, 2H), 1.29 (s, 6H).

Example 2B

[00117] Step 1: Under a nitrogen atmosphere, 2,2,6,6-tetramethylpiperidin-4-one (257.4 kg, 1658.0 mol, 1.00 eq.), tri-butyl methyl ammonium chloride (14.86 kg, 63.0 mol, 0.038 eq.), chloroform (346.5 kg, 2901.5 mol, 1.75 eq.) and DCM (683.3 kg) were added to a 500 L enamel reactor. The reaction was stirred at 85 rpm and cooled to 15~17°C. The solution of 50wt% sodium hydroxide (1061.4 kg, 13264.0 mol, 8.00 eq.) was added dropwise over 40 h while maintaining the temperature between 15~25°C. The reaction mixture was stirred and monitored by GC.

[00118] Step 2: The suspension was diluted with DCM (683.3 kg) and water (1544.4 kg). The organic phase was separated. The aqueous phase was extracted with DCM (683.3 kg). The organic phases were combined, cooled to 10°C and then 3 M

hydrochloric acid (867.8 kg, 2559.0 mol, 1.5 eq.) was added. The mixture was stirred at 10~15 °C for 2 h. The organic phase was separated. The aqueous phase was extracted with DCM (683.3 kg x 2). The organic phases were combined, dried over Na2SO4 (145.0 kg) for 6 h. The solid was filtered off and washed with DCM (120.0 kg). The filtrate was stirred with active charcoal (55 kg) for 6 h. The resulting mixture was filtered and the filtrate was concentrated under reduced pressure (30~40°C, -0.1MPa). Then isopropyl acetate (338 kg) was added and the mixture was heated to 87~91°C, stirred for 1 h. Then the solution was cooled to 15 °C in 18 h and stirred for 1 h at 15 °C. The solid was collected by filtration, washed with 50% isopropyl acetate/hexane (80.0 kg x 2) and dried overnight in the vacuum oven at 50 °C to afford 5,5-dimethyl-3-methylenepyrrolidin-2-one as an off white solid, 55% yield.

Example 3: Synthesis of (S)-3,5,5-trimethyl-pyrrolidin-2-one from 5,5-dimethyl-3- methylenepyrrolidin-2-one

Example 3A – Use of Rh Catalyst

Step 1 – Preparation of Rh Catalyst Formation:

[00119] In a 3 L Schlenk flask, 1.0 l of tetrahydrofurn (THF) was degassed with an argon stream. Mandyphos Ligand SL-M004-1 (1.89 g) and [Rh(nbd)Cl]2 (98%, 0.35 g) (chloronorbornadiene rhodium(I) dimer) were added. The resulting orange catalyst solution was stirred for 30 min at room temperature to form a catalyst solution.

Step 2:

[00120] A 50 L stainless steel autoclave was charged with 5,5-dimethyl-3-methylenepyrrolidin-2-one (6.0 kg) and THF (29 L). The autoclave was sealed and the resulting suspension was flushed with nitrogen (3 cycles at 10 bar), and then released of pressure. Next the catalyst solution from Step 1 was added. The autoclave was flushed with nitrogen without stirring (3 cycles at 5 bar) and hydrogen (3 cycles at 5 bar). The pressure was set to 5 bar and a 50 L reservoir was connected. After 1.5 h with stirring at 1000 rpm and no hydrogen uptake the reactor was flushed again with nitrogen (3 cycles at 10 bar) with stirring and additional catalyst solution was added. The autoclave was again flushed to hydrogen with the above described procedure (3 x 5 bar N2, 3 x 5 bar H2) and adjusted to 5 bar. After 2 h, the pressure was released, the autoclave was flushed with nitrogen (3 cycles at 5 bar) and the product solution was discharged into a 60 L inline barrel. The autoclave was charged again with THF (5 L) and stirred with 1200 rpm for 5 min. The wash solution was added to the reaction mixture.

Step 3:

[00121] The combined solutions were transferred into a 60 L reactor. The inline barrel was washed with 1 L THF which was also added into the reactor. 20 L THF were removed by evaporation at 170 mbar and 40°C.15 L heptane were added. The distillation was continued and the removed solvent was continuously replaced by heptane until the THF content in the residue was 1% w/w (determined by NMR). The reaction mixture was heated to 89°C (turbid solution) and slowly cooled down again (ramp: 14°C/h). Several heating and cooling cycles around 55 to 65°C were made. The off-white suspension was transferred to a stirred pressure filter and filtered (ECTFE-pad, d = 414 mm, 60 my, Filtration time = 5 min). 10 L of the mother liquor was transferred back into the reactor to wash the crystals from the reactor walls and the obtained slurry was also added to the filter. The collected solid was washed with 2 x 2.5 l heptane, discharged and let dry on the rotovap at 40°C and 4 mbar to obtain the product, (S)-3,5,5-trimethyl-pyrrolidin-2-one; 5.48Kg (91%), 98.0% ee.

Example 3B – Use of Ru Catalyst

[00122] The reaction was performed in a similar manner as described above in Example 3A except the use of a Ru catalyst instead of a Rh catalyst.

[00123] Compound (15) (300 g) was dissolved in THF (2640 g, 10 Vol) in a vessel. In a separate vessel, a solution of [RuCl(p-cymene){(R)-segphos}]Cl (0.439g, 0.0002 eq) in THF (660 g, 2.5 Vol) was prepared. The solutions were premixed in situ and passed through a Plug-flow reactor (PFR). The flow rate for the Compound (15) solution was at 1.555 mL/min and the Ru catalyst solution was at 0.287 mL/min. Residence time in the PFR was 4 hours at 30 °C, with hydrogen pressure of 4.5 MPa. After completion of reaction, the THF solvent was distilled off to give a crude residue. Heptane (1026 g, 5 vol) was added and the resulting mixture was heated to 90 °C. The mixture was seeded with 0.001 eq. of Compound 16S seeds. The mixture was cooled to -15 °C at 20 °C/h. After cooling, heptane (410 g, 2 vol) was added and the solid product was recovered by filtration. The resulting product was dried in a vacuum oven at 35 °C to give (S)-3,5,5-trimethyl-pyrrolidin-2-one (281.77 g, 98.2 % ee, 92 % yield).

Example 3C – Analytical Measurements

[00124] Analytical chiral HPLC method for the determination of the conversion, chemoselectivity, and enantiomeric excess of the products from Example 3A and 3B was made under the following conditions

Instrument: Agilent Chemstation 1100

Column: Phenomenex Lux 5u Cellulose-2, 4.6 mm x 250 mm x 5 um, LHS6247 Solvent: Heptane/iPrOH (90:10)

Flow: 1.0 ml/min

Detection: UV (210 nm)

Temperature: 25°C

Sample concentration: 30 μl of reaction solution evaporated, dissolved in 1 mL heptane/iPrOH (80/20)

Injection volume: 10.0 μL, Run time 20 min

Retention times:

5,5–‐dimethyl–3–methylenepyrrolidin–‐2–‐one: 13.8 min (S)-3,5,5-trimethyl-pyrrolidin-2-one: 10.6 min

(R)-3,5,5-trimethyl-pyrrolidin-2-one: 12.4 min

Example 4: Synthesis of (S)-3,5,5-trimethyl-pyrrolidin-2-one from 5,5-dimethyl-3- methylenepyrrolidin-2-one

[00125] Mandyphos (0.00479 mmol, 0.12 eq) was weighed into a GC vial. In a separate vial Ru(Me-allyl)2(COD) (16.87 mg, 0.0528 mmol) was weighed and dissolved in DCM (1328 µL). In another vial HBF4•Et2O (6.6 µL) and BF3 ^Et2O (2.0 µL) were dissolved in DCM (240 µL). To the GC vial containing the ligand was added, under a flow of argon, the Ru(Me-allyl)2(COD) solution (100 µL; 0.00399 mmol, 0.1eq) and the HBF4•Et2O / BF3 ^Et2O solution (20 µL; 1 eq HBF4 ^Et2O and catalytic BF3 ^Et2O). The resulting mixtures were stirred under a flow of argon for 30 minutes.

[00126] 5,5-dimethyl-3-methylenepyrrolidin-2-one (5 mg, 0.0399 mmol) in EtOH (1 mL) was added. The vials were placed in the hydrogenation apparatus. The apparatus was flushed with H2 (3×) and charged with 5 bar H2. After standing for 45 minutes, the apparatus was placed in an oil bath at temperature of 45°C. The reaction mixtures were stirred overnight under H2.200 µL of the reaction mixture was diluted with MeOH (800 µL) and analyzed for conversion and ee.

1H NMR (400 MHz, Chloroform-d) δ 6.39 (s, 1H), 2.62 (ddq, J = 9.9, 8.6, 7.1 Hz, 1H), 2.17 (ddd, J = 12.4, 8.6, 0.8 Hz, 1H), 1.56 (dd, J = 12.5, 9.9 Hz, 1H), 1.31 (s, 3H), 1.25 (s, 3H), 1.20 (d, J = 7.1 Hz, 3H).

Table 1: IPC method for Asymmetric Hydrogenation

Example 5. Synthesis of (S)-2,2,4-trimethylpyrrolidine hydrochloride from (S)- 3,5,5-trimethyl-pyrrolidin-2-one

Example 5A

[00127] Anhydrous THF (100ml) was charged to a dry 750ml reactor and the jacket temperature was set to 50°C. Once the vessel contents were at 50°C LiAlH4pellets (10g, 263mmol, 1.34 eq.) were added. The mixture was stirred for 10 minutes, then a solution of (S)-3,5,5-trimethyl-pyrrolidin-2-one (16S) (25g, 197mmol) in anhydrous THF (100ml) was added dropwise over 45 minutes, maintaining the temperature between 50-60°C. Once the addition was complete the jacket temperature was increased to 68°C and the reaction stirred for 18.5hrs. The reaction mixture was cooled to 30°C then saturated sodium sulfate solution (20.9ml) was added dropwise over 30 minutes, keeping the temperature below 40°C. Vigorous evolution of hydrogen was observed and the reaction mixture thickened but remained mixable. The mixture thinned towards the end of the addition. The mixture was cooled to 20°C, diluted with iPrOAc (100ml) and stirred for an additional 10 minutes. The suspension was then drained and collected through the lower outlet valve, washing through with additional iPrOAc (50ml). The collected suspension was filtered through a celite pad on a sintered glass funnel under suction and washed with iPrOAc (2x50ml).

[00128] The filtrate was transferred back to the cleaned reactor and cooled to 0°C under nitrogen. 4M HCl in dioxane (49.1ml, 197mmol, 1eq.) was then added dropwise over 15 minutes, maintaining the temperature below 20°C. A white precipitate formed. The reactor was then reconfigured for distillation, the jacket temperature was increased to 100 °C, and distillation of solvent was carried out. Additional i-PrOAc (100 mL) was added during concentration, after >100 mL distillate had been collected. Distillation was continued until ~250 mL total distillate was collected, then a Dean-Stark trap was attached and reflux continued for 1 hour. No water was observed to collect. The reaction mixture was cooled to 20 °C and filtered under suction under nitrogen. The filtered solid was washed with i-PrOAc (100 mL), dried under suction in nitrogen, then transferred to a glass dish and dried in a vacuum oven at 40 °C with a nitrogen bleed. (S)-2,2,4-Trimethylpyrrolidine hydrochloride (17S•HCl) was obtained as a white solid (24.2g, 82%).

GC analysis (purity): >99.5%

GC chiral purity: 99.5%

Water content (by KF): 0.074%

Residual solvent (by 1H-NMR): 0.41%

Example 5B

[00129] To a glass lined 120 L reactor was charged LiAlH4 pellets (2.5 kg 66 mol, 1.2 equiv.) and dry THF (60 L) and warmed to 30 °C. To the resulting suspension was

charged (S)-3,5,5-trimethylpyrrolidin-2-one (7.0 kg, 54 mol) in THF (25 L) over 2 hours while maintaining the reaction temperature at 30 to 40 °C. After complete addition, the reaction temperature was increased to 60 – 63 °C and maintained overnight. The reaction mixture was cooled to 22 °C and sampled to check for completion, then cautiously quenched with the addition of EtOAc (1.0 L, 10 moles, 0.16 eq) followed by a mixture of THF (3.4 L) and water (2.5 kg, 2.0 eq) then followed by a mixture of water (1.75 kg) with 50 % aqueous sodium hydroxide (750 g, 2 eq water with 1.4 eq sodium hydroxide relative to aluminum), followed by 7.5 L water (6 eq“Fieser” quench). After the addition was completed, the reaction mixture was cooled to room temperature, and the solid was removed by filtration and washed with THF (3 x 25 L). The filtrate and washings were combined and treated with 5.0 L (58 moles) of aqueous 37% HCl (1.05 equiv.) while maintaining the temperature below 30°C.

[00130] The resultant solution was concentrated by vacuum distillation to a slurry in two equal part lots on the 20 L Buchi evaporator. Isopropanol (8 L) was charged and the solution reconcentrated to near dryness by vacuum distillation. Isopropanol (4 L) was added and the product slurried by warming to about 50 °C. Distillation from Isopropanol continued until water content by KF is≤ 0.1 %. Methyl tertbutyl ether (6 L) was added and the slurry cooled to 2-5 °C. The product was collected by filtration and rinsed with 12 L methyl tert-butyl ether and pulled dry with a strong nitrogen flow and further dried in a vacuum oven (55 °C/300 torr/N2bleed) to afford (S)-2,2,4-trimethylpyrrolidine•HCl as a white, crystalline solid (6.21 kg, 75% yield). 1H NMR (400 MHz, DMSO-d6) δ 9.34 (s, 2H), 3.33 (dd, J = 11.4, 8.4 Hz, 1H), 2.75 (dd, J = 11.4, 8.6 Hz, 1H), 2.50– 2.39 (m, 1H), 1.97 (dd, J = 12.7, 7.7 Hz, 1H), 1.42 (s, 3H), 1.38 (dd, J = 12.8, 10.1 Hz, 1H), 1.31 (s, 3H), 1.05 (d, J = 6.6 Hz, , 3H).

Example 5C

[00131] With efficient mechanical stirring, a suspension of LiAlH4 pellets (100 g 2.65 mol; 1.35 eq.) in THF (1 L; 4 vol. eq.) warmed at a temperature from 20 °C– 36 °C (heat of mixing). A solution of (S)-3,5,5-trimethylpyrrolidin-2-one (250 g; 1.97 mol) in THF (1 L; 4 vol. eq.) was added to the suspension over 30 min. while allowing the reaction temperature to rise to ~60 °C. The reaction temperature was increased to near reflux (~68 °C) and maintained for about 16 h. The reaction mixture was cooled to below 40 °C and cautiously quenched with drop-wise addition of a saturated aqueous solution of Na2SO4 (209 mL) over 2 h. After the addition was completed, the reaction mixture was cooled to ambient temperature, diluted with i-PrOAc (1 L), and mixed thoroughly. The solid was removed by filtration (Celite pad) and washed with i-PrOAc (2 x 500 mL). With external cooling and N2 blanket, the filtrate and washings were combined and treated with drop-wise addition of anhydrous 4 M HCl in dioxane (492 mL; 2.95 mol; 1 equiv.) while maintaining the temperature below 20 °C. After the addition was completed (20 min), the resultant suspension was concentrated by heating at reflux (74– 85 °C) and removing the distillate. The suspension was backfilled with i-PrOAc (1 L) during concentration. After about 2.5 L of distillate was collected, a Dean-Stark trap was attached and any residual water was azeotropically removed. The suspension was cooled to below 30 °C when the solid was collected by filtration under a N2 blanket. The solid is dried under N2 suction and further dried in a vacuum oven (55 °C/300 torr/N2 bleed) to afford 261 g (89% yield) of (S)-2,2,4-trimethylpyrrolidine•HCl as a white, crystalline solid. 1H NMR (400 MHz, DMSO-d6) δ 9.34 (s, 2H), 3.33 (dd, J = 11.4, 8.4 Hz, 1H), 2.75 (dd, J = 11.4, 8.6 Hz, 1H), 2.50– 2.39 (m, 1H), 1.97 (dd, J = 12.7, 7.7 Hz, 1H), 1.42 (s, 3H), 1.38 (dd, J = 12.8, 10.1 Hz, 1H), 1.31 (s, 3H), 1.05 (d, J = 6.6 Hz, 3H). 1H NMR (400 MHz, CDCl3) δ 9.55 (d, J = 44.9 Hz, 2H), 3.52 (ddt, J = 12.1, 8.7, 4.3 Hz, 1H), 2.94 (dq, J = 11.9, 5.9 Hz, 1H), 2.70– 2.51 (m, 1H), 2.02 (dd, J = 13.0, 7.5 Hz, 1H), 1.62 (s, 3H), 1.58– 1.47 (m, 4H), 1.15 (d, J = 6.7 Hz, 3H).

Example 5D

[00132] A 1L four-neck round bottom flask was degassed three times. A 2M solution of LiAlH4 in THF (100 mL) was charged via cannula transfer. (S)-3,5,5-trimethylpyrrolidin-2-one (19.0 g) in THF (150 mL) was added dropwise via an addition funnel over 1.5 hours at 50-60 °C, washing in with THF (19 mL). Upon completion of the addition, the reaction was stirred at 60 °C for 8 hours and allowed to cool to room temperature overnight. GC analysis showed <1% starting material remained.

[00133] Deionized water (7.6 mL) was added slowly to the reaction flask at 10-15 °C, followed by 15% potassium hydroxide (7.6 mL). Isopropyl acetate (76 mL) was added, the mixture was stirred for 15 minutes and filtered, washing through with isopropyl acetate (76 mL).

[00134] The filtrate was charged to a clean and dry 500 mL four neck round bottom flask and cooled to 0-5 °C. 36% Hydrochloric acid (15.1 g, 1.0 eq.) was added keeping the temperature below 20 °C. Distillation of the solvent, backfilling with isopropyl acetate (190 mL), was carried out to leave a residual volume of ~85 mL. Karl Fischer analysis = 0.11% w/w H2O. MTBE (methyl tertiary butyl ether) (19 mL) was added at 20-30 °C and the solids were filtered off under nitrogen at 15-20 °C, washing with isopropyl acetate (25 mL) and drying under vacuum at 40-45 °C to give crude (S)-2,2,4-trimethylpyrrolidine hydrochloride as a white crystalline solid (17.4 g, 78% yield). GC purity = 99.5%. Water content = 0.20% w/w. Chiral GC gave an ee of 99.0% (S).

Ruthenium content = 0.004 ppm. Lithium content = 0.07 ppm.

[00135] A portion of the dried crude (S)-2,2,4-trimethylpyrrolidine hydrochloride (14.3g) was charged to a clean and dry 250 mL four-neck round bottom flask with isopropanol (14.3 mL) and the mixture held at 80-85 °C (reflux) for 1 hour to give a clear solution. The solution was allowed to cool to 50 °C (solids precipitated on cooling) then MTBE (43 mL) was added and the suspension held at 50-55 °C (reflux) for 3 hours. The solids were filtered off at 10 °C, washing with MTBE (14 mL) and dried under vacuum at 40 °C to give recrystallised (S)-2,2,4-trimethylpyrrolidine hydrochloride (17S•HCl) as a white crystallised solid (13.5 g, 94% yield on recrystallisation, 73% yield). GC purity = 99.9%. Water content = 0.11% w/w. Chiral GC gave an ee of 99.6 (S). Ruthenium content = 0.001 ppm. Lithium content = 0.02 ppm.

Example 5E:

[00136] A reactor was charged with lithium aluminum hydride (LAH) (1.20 equiv.) and 2-MeTHF (2-methyltetrahydrofuran) (4.0 vol), and heated to internal temperature of 60 °C while stirring to disperse the LAH. A solution of (S)-3,5,5-trimethylpyrrolidin-2-one (1.0 equiv) in 2-MeTHF (6.0 vol) was prepared and stirred at 25 °C to fully dissolve the (S)-3,5,5-trimethylpyrrolidin-2-one. The (S)-3,5,5-trimethylpyrrolidin-2-one solution was added slowly to the reactor while keeping the off-gassing manageable, followed by rinsing the addition funnel with 2-MeTHF (1.0 vol) and adding it to the reactor. The reaction was stirred at an internal temperature of 60 ± 5 °C for no longer than 6 h. The internal temperature was set to 5 ± 5 °C and the agitation rate was increased. A solution of water (1.35 equiv.) in 2-MeTHF (4.0v) was prepared and added slowly to the reactor while the internal temperature was maintained at or below 25 °C. Additional water (1.35 equiv.) was charged slowly to the reactor while the internal temperature was maintained at or below 25 °C. Potassium hydroxide (0.16 equiv.) in water (0.40 vol) was added to the reactor over no less than 20 min while the temperature was maintained at or below 25 °C. The resulting solids were removed by filtration, and the reactor and cake were washed with 2-MeTHF (2 x 2.5 vol). The filtrate was transferred back to a jacketed

vessel, agitated, and the temperature was adjusted to 15 ± 5 °C. Concentrated aqueous HCl (35-37%, 1.05 equiv.) was added slowly to the filtrate while maintaining the temperature at or below 25 °C and was stirred no less than 30 min. Vacuum was applied and the solution was distilled down to a total of 4.0 volumes while maintaining the internal temperature at or below 55 °C, then 2-MeTHF (6.00 vol) was added to the vessel. The distillation was repeated until Karl Fischer analysis (KF) < 0.20% w/w H2O. Isopropanol was added (3.00 vol), and the temperature was adjusted to 70 °C (65– 75 °C) to achieve a homogenous solution, and stirred for no less than 30 minutes at 70 °C. The solution was cooled to 50 °C (47– 53 °C) over 1 hour and stirred for no less than 1 h, while the temperature was maintained at 50°C (47– 53 °C). The resulting slurry was cooled to -10 °C (-15 to -5°C) linearly over no less than 12 h. The slurry was stirred at -10 °C for no less than 2 h. The solids were isolated via filtration or centrifugation and were washed with a solution of 2-MeTHF (2.25 vol) and IPA (isopropanol) (0.75 vol). The solids were dried under vacuum at 45 ± 5 °C for not less than 6 h to yield (S)-2,2,4-trimethylpyrrolidine hydrochloride (17S•HCl).

Example 6: Phase Transfer Catalyst (PTC) Screens for the Synthesis of 5,5- dimethyl-3-methylenepyrrolidin-2-one

[00137] 2,2,6,6-tetramethylpiperidin-4-one (500.0 mg, 3.06 mmol, 1.0 eq.), PTC (0.05 eq.), and chloroform (0.64 g, 0.4 mL, 5.36 mmol, 1.75 eq.) were charged into a vial equipped with a magnetic stir bar. The vial was cooled in an ice bath and a solution of 50 wt% sodium hydroxide (0.98 g, 24.48 mmol, 8.0 eq.) was added dropwise over 2 min. The reaction mixture was stirred until completion as assessed by GC analysis. The reaction mixture was diluted with DCM (2.0 mL, 4.0v) and H2O (3.0 mL, 6.0v). The phases were separated and the aqueous phase was extracted with DCM (1.0 mL, 2.0v). The organic phases were combined and 2 M hydrochloric acid (0.17 g, 2.3 mL, 4.59 mmol, 1.5 eq.) was added. The reaction mixture was stirred until completion and assessed by HPLC. The aqueous phase was saturated with NaCl and the phases were separated. The aqueous phase was extracted with DCM (1.0 mL, 2.0v) twice, the

organic phases were combined, and 50 mg of biphenyl in 2 mL of MeCN was added as an internal HPLC standard. Solution yield was assessed by HPLC. Reaction results are summarized in Table 2.

Table 2

Example 7: Solvent Screens for the Synthesis of 5,5-dimethyl-3- methylenepyrrolidin-2-one

[00138] 2,2,6,6-tetramethylpiperidin-4-one (500.0 mg, 3.06 mmol, 1.0 eq.), tetrabutylammonium hydroxide (0.12 g, 0.153 mmol, 0.050 eq), chloroform (0.64 g, 0.4 mL, 5.36 mmol, 1.75 eq.), and solvent (2 vol. or 4 vol., as shown in Table 3 below) were charged into a vial equipped with a magnetic stir bar. The vial was cooled in an ice bath and a solution of 50 wt% sodium hydroxide (0.98 g, 24.48 mmol, 8.0 eq.) was added drop wise over 2 min. The reaction mixture was stirred until completion and assessed by GC analysis. The reaction mixture was diluted with DCM (2.0 mL, 4.0v) and H2O (3.0 mL, 6.0v). The phases were separated and the aqueous phase was extracted with DCM (1.0 mL, 2.0v). The organic phases were combined and 2 M hydrochloric acid (0.17 g, 2.3 mL, 4.59 mmol, 1.5 eq.) was added. The reaction mixture was stirred until completion, assessed by HPLC. The aqueous phase was saturated with NaCl and the phases were separated. The aqueous phase was extracted with DCM (1.0 mL,

2.0v) twice, the organic phases were combined, and 50 mg of biphenyl in 2 mL of MeCN was added as an internal HPLC standard. Solution yield was assessed by HPLC.

Reaction results are summarized in Table 3.

Table 3

Example 8: Base Screens for the Synthesis of 5,5-dimethyl-3-methylenepyrrolidin- 2-one

[00139] 2,2,6,6-tetramethylpiperidin-4-one (500.0 mg, 3.06 mmol, 1.0 eq.), tetrabutylammonium hydroxide (0.12 g, 0.153 mmol, 0.050 eq), and chloroform (0.64 g, 0.4 mL, 5.36 mmol, 1.75 eq.) were charged into a vial equipped with a magnetic stir bar. The vial was cooled in an ice bath, and a solution of an amount wt% sodium hydroxide as shown in Table 4 below in water (0.98 g, 24.48 mmol, 8.0 eq.) was added drop wise over 2 min. The reaction mixture was stirred until completion and assessed by GC analysis. The reaction mixture was diluted with DCM (2.0 mL, 4.0v) and H2O (3.0 mL, 6.0v). The phases were separated and the aqueous phase is extracted with DCM (1.0 mL, 2.0v). The organic phases were combined and 2 M hydrochloric acid (0.17 g, 2.3 mL, 4.59 mmol, 1.5 eq.) was added. The reaction mixture was stirred until completion, assessed by HPLC. The aqueous phase was saturated with NaCl and the phases were separated. The aqueous phase was extracted with DCM (1.0 mL, 2.0v) twice, the organic phases were combined, and 50 mg of biphenyl in 2 mL of MeCN was added as

an internal HPLC standard. Solution yield was assessed by HPLC. Reaction results are summarized in Table 4.

Table 4

Example 9: Various Amounts of Phase Transfer Catalyst (PTC) for the Synthesis of 5,5-dimethyl-3-methylenepyrrolidin-2-one

[00140] In this experiment, various amounts of PTCs were tested as described below: Tetrabutylammonium hydroxide (0.01 eq.), TBAB (0.01 eq.), Tributylmethylammonium chloride (0.01 eq.), Tetrabutylammonium hydroxide (0.02 eq.), TBAB (0.02 eq.), Tributylmethylammonium chloride (0.02 eq.), Tetrabutylammonium hydroxide (0.03 eq.), TBAB (0.03 eq.), Tributylmethylammonium chloride (0.03 eq.).

[00141] 2,2,6,6-tetramethylpiperidin-4-one (500.0 mg, 3.06 mmol, 1.0 eq.), PTC (0.12 g, 0.153 mmol, 0.050 eq), and chloroform (1.75 eq.) were charged into a vial equipped with a magnetic stir bar. The vial was cooled in an ice bath, and a solution of 50 wt% sodium hydroxide (0.98 g, 24.48 mmol, 8.0 eq.) was added drop wise over 2 min. The reaction mixture was stirred until completion, assessed by GC analysis. The reaction mixture was diluted with DCM (2.0 mL, 4.0v) and H2O (3.0 mL, 6.0v). The phases were separated and the aqueous phase was extracted with DCM (1.0 mL, 2.0v). The organic phases were combined and 2 M hydrochloric acid (0.17 g, 2.3 mL, 4.59 mmol, 1.5 eq.) was added. The reaction mixture was stirred until completion, assessed by

HPLC. The aqueous phase was saturated with NaCl and the phases were separated. The aqueous phase was extracted with DCM (1.0 mL, 2.0v) twice, the organic phases were combined, and 50 mg of biphenyl in 2 mL of MeCN was added as an internal HPLC standard. Solution yield was assessed by HPLC. The reaction results are summarized in Table 5.

Table 5

Example 10: Preparation of 2,2,6,6-tetramethylpiperidin-4-one hydrochloride (14•HCl)

[00142] 2,2,6,6-tetramethyl-4-piperidinone (14) (30 g, 193.2 mmol, 1.0 eq) was charged to a 500 mL nitrogen purged three necked round bottomed flask equipped with condenser. IPA (300 mL, 10 vol) was added to the flask and the mixture heated to 60 °C until dissolved.

[00143] To the solution at 60 °C was added 5-6 M HCl in IPA (40 mL, 214.7 mmol, 1.1 eq) over 10 min and the resulting suspension stirred at 60 °C for 30 min then allowed to cool to ambient temperature. The suspension was stirred at ambient temperature overnight, then filtered under vacuum and washed with IPA (3 x 60 mL, 3 x 2 vol). The cream colored solid was dried on the filter under vacuum for 10 min.

[00144] The wet cake was charged to a 1 L nitrogen purged three necked round bottomed flask equipped with condenser. IPA (450 mL, 15 vol) was added to the flask and the suspension heated to 80 °C until dissolved. The mixture was allowed to cool slowly to ambient temperature over 3 h and the resulting suspension stirred overnight at ambient temperature.

[00145] The suspension was filtered under vacuum, washed with IPA (60 mL, 2 vol) and dried on the filter under vacuum for 30 min. The resulting product was dried in a vacuum oven at 40 °C over the weekend to give 2,2,6,6-tetramethylpiperidin-4-one hydrochloride (14•HCl) a white crystalline solid, 21.4 g, 64% yield.

Example 11: Synthesis of (S)-2,2,4-trimethylpyrrolidine hydrochloride (17S•HCl) from (S)-3,5,5-trimethyl-pyrrolidin-2-one (16S)

[00146] Each reactor was charged with (S)-3,5,5-trimethyl-pyrrolidin-2-one (16S) in THF, H2, and the catalyst shown in the below table. The reactor was heated to 200 °C and pressurized to 60 bar, and allowed to react for 12 hours. GC analysis showed that (S)-2,2,4-trimethylpyrrolidine was produced in the columns denoted by“+.”

[00147] A 2.5% solution of (S)-3,5,5-trimethyl-pyrrolidin-2-one (16S) in THF was flowed at 0.05 mL/min into a packed bed reactor prepacked with 2% Pt-0.5%Sn/SiO2 catalyst immobilized on silica gel. H2 gas was also flowed into the packed bed reactor at 20 mL/min. The reaction was carried out at 130 °C under 80 bar pressure with a WHSV (Weigh Hourly Space Velocity) of 0.01-0.02 h-1. The product feed was collected in a batch tank and converted to (S)-2,2,4-trimethylpyrrolidine HCl in batch mode: 36% Hydrochloric acid (1.1 eq.) was added keeping the temperature below 20 °C. Distillation of the solvent, backfilling with isopropyl acetate (4v), was carried out to leave a residual volume of 5v. Karl Fischer analysis < 0.2% w/w H2O. MTBE (methyl tertiary butyl ether) (1v) was added at 20-30 °C and the solids were filtered off under nitrogen at 15-20 °C, washing with isopropyl acetate (1.5v) and drying under vacuum at 40-45 °C to give (S)-2,2,4-trimethylpyrrolidine hydrochloride (17S•HCl) as a white crystalline solid (74.8% yield, 96.1% ee).

Alternate synthesis

[00148] A 2.5% solution of (S)-3,5,5-trimethyl-pyrrolidin-2-one (16S) in THF was flowed at 0.05 mL/min into a packed bed reactor prepacked with 4% Pt-2%Sn/TiO2catalyst immobilized on silica gel. H2 gas was also flowed into the packed bed reactor at 20 mL/min. The reaction was carried out at 200 °C under 50 bar pressure with a WHSV (Weigh Hourly Space Velocity) of 0.01-0.02 h-1. The product feed was collected in a batch tank and converted to (S)-2,2,4-trimethylpyrrolidine HCl in batch mode: 36% Hydrochloric acid (1.1 eq.) was added keeping the temperature below 20 °C. Distillation of the solvent, backfilling with isopropyl acetate (4v), was carried out to leave a residual volume of 5v. Karl Fischer analysis < 0.2% w/w H2O. MTBE (methyl tertiary butyl ether) (1v) was added at 20-30 °C and the solids were filtered off under nitrogen at 15-20 °C, washing with isopropyl acetate (1.5v) and drying under vacuum at 40-45 °C to give (S)-2,2,4-trimethylpyrrolidine hydrochloride (17S•HCl) as a white crystalline solid (88.5% yield, 29.6% ee).

Alternate synthesis

[00149] A 2.5% solution of (S)-3,5,5-trimethyl-pyrrolidin-2-one (16S) in THF was flowed at 0.05 mL/min into a packed bed reactor prepacked with 2% Pt-0.5%Sn/TiO2 catalyst immobilized on silica gel. H2 gas was also flowed into the packed bed reactor at 20 mL/min. The reaction was carried out at 150 °C under 50 bar pressure with a WHSV (Weigh Hourly Space Velocity) of 0.01-0.02 h-1. The product feed was collected in a batch tank and converted to (S)-2,2,4-trimethylpyrrolidine HCl in batch mode: 36% Hydrochloric acid (1.1 eq.) was added keeping the temperature below 20 °C. Distillation of the solvent, backfilling with isopropyl acetate (4v), was carried out to leave a residual volume of 5v. Karl Fischer analysis < 0.2% w/w H2O. MTBE (methyl tertiary butyl ether) (1v) was added at 20-30 °C and the solids were filtered off under nitrogen at 15-20 °C, washing with isopropyl acetate (1.5v) and drying under vacuum at 40-45 °C to give (S)-2,2,4-trimethylpyrrolidine hydrochloride (17S•HCl) as a white crystalline solid (90.9% yield, 98.0% ee).

Alternate synthesis

[00150] A 2.5% solution of (S)-3,5,5-trimethyl-pyrrolidin-2-one (16S) in THF was flowed at 0.03 mL/min into a packed bed reactor prepacked with 2% Pt-8%Sn/TiO2catalyst immobilized on silica gel. H2 gas was also flowed into the packed bed reactor at 40 mL/min. The reaction was carried out at 180 °C under 55 bar pressure with a residence time of 6 min. The product feed was collected in a batch tank and converted to (S)-2,2,4-trimethylpyrrolidine HCl in batch mode: 36% Hydrochloric acid (1.1 eq.) was added keeping the temperature below 20 °C. Distillation of the solvent, backfilling with isopropyl acetate (4v), was carried out to leave a residual volume of 5v. Karl Fischer analysis < 0.2% w/w H2O. MTBE (methyl tertiary butyl ether) (1v) was added at 20-30 °C and the solids were filtered off under nitrogen at 15-20 °C, washing with isopropyl acetate (1.5v) and drying under vacuum at 40-45 °C to give (S)-2,2,4-trimethylpyrrolidine hydrochloride (17S•HCl) as a white crystalline solid (90.4% yield, 96.8% ee).

Example 12: Preparation of N-(1,3-dimethylpyrazol-4-yl)sulfonyl-6-[3-(3,3,3- trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]-2-[(4S)-2,2,4- trimethylpyrrolidin-1-yl]pyridine-3-carboxamide (Compound 1)


Compound 1

I. Preparation of Starting Materials:

A. Synthesis of 3,3,3-Trifluoro-2,2-dimethylpropionic acid (31), morpholine salt:

Step 1: tert-Butyl((1-ethoxy-2-methylprop-1-en-1-yl)oxy)dimethylsilane (28)

[00151] A 2L 3-necked round-bottom flask, equipped with a J-Kem thermocouple and an overhead stirrer, was purged with nitrogen for >20 minutes. Hexyllithium solution (2.3 M in hexanes; 1.05 equiv; 0.260 L, 597 mmol) was transferred into the flask via cannula. The flask was then cooled to–65°C in a dry ice/isopropyl alcohol bath and diisopropylamine (1.05 equiv; 0.842 L; 597mmol) was added via an addition funnel, and the internal temperature was maintained at–40 ±5 °C. Once the diisopropylamine addition was complete, tetrahydrofuran (THF) (0.423 L; 6.4 vol) was added to the reactor and the reaction was warmed to room temperature and stirred for 15 minutes. The solution was then cooled to–60 °C and ethyl isobutyrate (1.0 equiv; 0.754 L; 568 mmol) was added dropwise maintaining the temperature below–45 °C. 1,3-Dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (DMPU) (0.9 equiv; 0.616 L; 511 mmol) was then added dropwise to the reaction flask and the temperature was maintained below–45 °C. In a separate flask, tert-butyldimethylsilyl chloride (TBSCl) (1.05 equiv; 89.9 g; 597 mmol) was dissolved in THF (2.2 vol w.r.t. TBSCl) and then added to the 2L reactor. The internal temperature was maintained at≤–30°C during the addition of the TBSCl solution. The resulting reaction mixture was allowed to warm to room

temperature and stirred overnight under inert atmosphere. The reaction solution was transferred to a 2L one-neck round-bottom flask. Additional THF (50 mL, x 2) was used to rinse and transfer. The solution was concentrated in vacuo to remove most of the THF. Hexanes were added to the concentrated tert-butyl((1-ethoxy-2-methylprop-1-en-1-yl)oxy)dimethylsilane (500 mL). The organic phase was washed with three times with water (500 mL x 3), to remove salts. The organic layer was dried over Na2SO4 (100 g). The solution was filtered and the waste cake washed with additional hexanes (100 mL). The resulting hexanes solution of tert-butyl((1-ethoxy-2-methylprop-1-en-1-yl)oxy)dimethylsilane was concentrated in vacuo. A quantitative 1H-NMR assay was performed with benzyl benzoate as an internal standard. The quantitative NMR assay indicated that 108.6 grams of tert-butyl((1-ethoxy-2-methylprop-1-en-1-yl)oxy)dimethylsilane (83% yield) was present, and that 1.2 mol% of ethyl isobutyrate relative to tert-butyl((1-ethoxy-2-methylprop-1-en-1-yl)oxy)dimethylsilane was also present. The resulting tert-butyl((1-ethoxy-2-methylprop-1-en-1-yl)oxy)dimethylsilane solution was used without further purification for the photochemical reaction of Step 2.  Step 2: 3,3,3-Trifluoro-2,2-dimethylpropionic acid (31), morpholine salt

[00152] Stock solution A: The concentrated tert-butyl((1-ethoxy-2-methylprop-1-en-1- yl)oxy)dimethylsilane (198 g; 0.86 mol) was dissolved in acetonitrile (895 g; 1.14 L; 5.8 vol) to give a cloudy, yellow solution that was then filtered. The density of the clear, filtered solution was measured to be 0.81 g/mL and the molar concentration was calculated to be 0.6 M. This is referred to as stock solution A (substrate).

[00153] Stock solution B: The catalyst and reagent solution was prepared by dissolving Ru(bpy)3Cl2 hexahydrate in acetonitrile, followed by adding ethanol and pyrrolidine to give a red-colored solution (density measured: 0.810 g/mL). The molar concentration of the catalyst was calculated to be 0.00172 M. The molar concentration of the solution with respect to EtOH/pyrrolidine was calculated to be ~2.3 M. See Table 6.

Table 6

(i) Photochemical Trifluoromethylation

[00154] CF3I gas was delivered to the reactor directly from the lecture bottle using a regulator and mass flow controller. Stock solutions A and B were pumped at 6.7 g/min and 2.07 g/min, respectively, to mix in a static mixer. The resulting solution was then combined with CF3I in a static mixer. The CF3I was metered into the reactor via a mass flow controller at 2.00 g/min (2 equiv). Liquid chromatography (LC) assay indicated that 1.0% of the tert-butyl((1-ethoxy-2-methylprop-1-en-1-yl)oxy)dimethylsilane was left unreacted. Details of the reaction parameters are shown in the table below. The reaction stream was passed through the 52 mL photoreactor while being irradiated with the 800 W 440-445 LED light source. The first 5 minutes of eluent was discarded. Thereafter the eluent was collected for a total of 3.05 hours. A total of ~2.3 L of solution was collected during the reaction (~1.06 mol). See Table 7.

Table 7

(ii) Saponification & Salt Formation

[00155] The saponication of the crude solution (4.1 L, from 1.60 mol tert-butyl((1-ethoxy-2-methylprop-1-en-1-yl)oxy)dimethylsilane) was carried out in a 5L 4-necked round-bottomed flask in 2 roughly equal size batches using 15 wt% NaOH (aq) (total ~320g NaOH) at 50 °C for 2-4 h. Upon completion of the reaction determined by gas chromatography (GC) analysis, the re-combined batches were cooled to room

temperature and hexanes (500 mL) and toluene (500 mL) were added to give a clear phase separation. The top organic layer was washed with half-brine (1 L) and combined with the first portion of the product-containing aqueous solution (4.5 L). The combined aqueous stream was washed with hexanes (500 mL) and concentrated to 2-3 L to remove a majority of volatile acetonitrile. To the aqueous phase was added concentrated HCl (1 L, 12 N) and the resulting mixture was extracted with hexanes (4 x 1 L). The combined hexanes extracts were washed with half brine (2 x 500 mL) and concentrated to give an oil (216 g). The oil was dissolved in THF (580 mL), and morpholine (120 mL, 1.0 equiv) was added slowly via an addition funnel. Upon completion of addition, the batch was seeded (0.5-1 g) with morpholine salt, and the seeds were held and allowed to thicken over 30 min. Hexanes (1660 mL) were added over ~ 2 h, and the mixture was aged for another 3 h. The batch was filtered, washed with hexanes (~500 mL) in portions and dried under vacuum/dry air flush to give 3,3,3-trifluoro-2,2-dimethylpropionic acid, morpholine salt as a white solid (283 g, 73%).1H NMR (400 MHz, CD3OD) δ 3.84-3.86 (m, 4H), 3.15-3.18 (m, 4H), 1.33 (s, 6H); 19F NMR (376 MHz, CD3OD): δ -75.90 (s, 3F).

B. Synthesis of 3,3,3-Trifluoro-2,2-dimethyl-propan-1-ol (5)

[00156] A 1 L 3 neck round bottom flask was fitted with a mechanical stirrer, a cooling bath, an addition funnel, and a J-Kem temperature probe. The vessel was charged with lithium aluminum hydride (LAH) pellets (6.3 g, 0.1665 mol) under a nitrogen atmosphere. The vessel was then charged with tetrahydrofuran (200 mL) under a nitrogen atmosphere. The mixture was allowed to stir at room temperature for 0.5 hours to allow the pellets to dissolve. The cooling bath was then charged with crushed ice in water and the reaction temperature was lowered to 0 oC. The addition funnel was charged with a solution of 3,3,3-trifluoro-2,2-dimethyl-propanoic acid (20 g, 0.1281 mol) in tetrahydrofuran (60 mL) and the clear pale yellow solution was added drop wise over 1 hour. After the addition was complete the mixture was allowed to slowly warm to room temperature and stirring was continued for 24 hours. The suspension was cooled to 0 oC with a crushed ice-water in the cooling bath and then quenched by the very slow and drop wise addition of water (6.3 ml), followed by sodium hydroxide solution (15 weight %; 6.3 mL) and then finally with water (18.9 mL). The reaction temperature of the resulting white suspension was recorded at 5 oC. The suspension was stirred at ~5 oC for 30 minutes and then filtered through a 20 mm layer of Celite. The filter cake was washed with tetrahydrofuran (2 x 100 mL). The filtrate was dried over sodium sulfate (150 g) and then filtered. The filtrate was concentrated under reduced pressure to provide a clear colorless oil (15 g) containing a mixture of the product 3,3,3-trifluoro-2,2-dimethyl-propan-1-ol in THF (73 % weight of product ~10.95g, and 27 wt.% THF as determined by 1H-NMR). The distillate from the rotary evaporation was distilled at atmospheric pressure using a 30 cm Vigreux column to provide 8.75 g of a residue containing 60 % weight of THF and 40 % weight of product (~3.5 g), which corresponds to 14.45 g (79% yield).1H NMR (400 MHz, DMSO-d6) δ 4.99 (t, J = 5.7 Hz, 1H), 3.38 (dd, J = 5.8, 0.9 Hz, 2H), 1.04 (d, J = 0.9 Hz, 6H).

C. Synthesis of tert-Butyl 3-oxo-2,3-dihydro-1H-pyrazole-1-carboxylate (22)

[00157] A 50L Syrris controlled reactor was started and the jacket was set to 20 °C, stirring at 150 rpm, reflux condenser (10 °C) and nitrogen purge. MeOH (2.860 L) and methyl (E)-3-methoxyprop-2-enoate (2.643 kg, 22.76 mol) were added and the reactor was capped. The reaction was heated to an internal temperature of 40 °C and the system was set to hold jacket temp at 40 °C. Hydrazine hydrate (1300 g of 55 %w/w, 22.31 mol) was added portion wise via addition funnel over 30 min. The reaction was heated to 60 ^C for 1 h. The reaction mixture was cooled to 20 ^C and triethylamine (2.483 kg, 3.420 L, 24.54 mol) was added portion wise, maintaining reaction temp <30 °C. A solution of Boc anhydride (di-tert-butyl dicarbonate) (4.967 kg, 5.228 L, 22.76 mol) in MeOH (2.860 L) was added portion wise maintaining temperature <45 °C. The reaction mixture was stirred at 20 ^C for 16 h. The reaction solution was partially concentrated to remove MeOH, resulting in a clear light amber oil. The resulting oil was transferred to the 50L reactor, stirred and added water (7.150 L) and heptane (7.150 L). The additions caused a small amount of the product to precipitate. The aqueous layer was drained into a clean container and the interface and heptane layer were filtered to separate the solid (product). The aqueous layer was transferred back to the reactor, and the collected solid was placed back into the reactor and mixed with the aqueous layer. A dropping funnel was added to the reactor and loaded with acetic acid (1.474 kg, 1.396 L, 24.54 mol), then began dropwise addition of acid. The jacket was set to 0 °C to absorb the quench exotherm. After addition (pH=5), the reaction mixture was stirred for 1 h. The solid was collected by filtration and washed with water (7.150 L) and washed a second time with water (3.575 L) and pulled dry. The crystalline solid was scooped out of the filter into a 20L rotovap bulb and heptane (7.150 L) was added. The mixture was slurried at 45 °C for 30 mins, and then 1-2 volumes of solvent was distilled off. The slurry in the rotovap flask was filtered and the solids washed with heptane (3.575 L) and pulled dry. The solid was further dried in vacuo (50 °C, 15 mbar) to give tert-butyl 5-oxo-1H-pyrazole-2-carboxylate (2921 g, 71%) as coarse solid.1H NMR (400 MHz, DMSO-d6) δ 10.95 (s, 1H), 7.98 (d, J = 2.9 Hz, 1H), 5.90 (d, J = 2.9 Hz, 1H), 1.54 (s, 9H).

II. Preparation of Compound I

Step A: tert-Butyl 3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazole-1-carboxylate (23)

[00158] A mixture of 3,3,3-trifluoro-2,2-dimethyl-propan-1-ol (10 g, 70.36 mmol) and tert-butyl 3-hydroxypyrazole-1-carboxylate (12.96 g, 70.36 mmol) in toluene (130 mL) was treated with triphenyl phosphine (20.30 g, 77.40 mmol) followed by isopropyl N-

isopropoxycarbonyliminocarbamate (14.99 mL, 77.40 mmol) and the mixture was stirred at 110 °C for 16 hours. The yellow solution was concentrated under reduced pressure, diluted with heptane (100mL) and the precipitated triphenylphosphine oxide was removed by filtration and washed with heptane/toluene 4:1 (100mL). The yellow filtrate was evaporated and the residue purified by silica gel chromatography with a linear gradient of ethyl acetate in hexane (0-40%) to give tert-butyl 3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazole-1-carboxylate (12.3 g, 57%) as an off white solid. ESI-MS m/z calc.308.13477, found 309.0 (M+1) +; Retention time: 1.84 minutes.1H NMR (400 MHz, DMSO-d6) δ 8.10 (d, J = 3.0 Hz, 1H), 6.15 (d, J = 3.0 Hz, 1H), 4.18 (s, 2H), 1.55 (s, 9H), 1.21 (s, 6H).

Step B: 3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)-1H-pyrazole (7)

[00159] tert-Butyl 3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazole-1-carboxylate (13.5 g, 43.79 mmol) was treated with 4 M hydrogen chloride in dioxane (54.75 mL, 219.0 mmol) and the mixture was stirred at 45 °C for 1 hour. The reaction mixture was evaporated to dryness and the residue was extracted with 1 M aqueous NaOH (100ml) and methyl tert-butyl ether (100ml), washed with brine (50ml) and extracted with methyl tert-butyl ether (50ml). The combined organic phases were dried, filtered and evaporated to give 3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)-1H-pyrazole (9.0 g, 96%) as an off white solid. ESI-MS m/z calc.208.08235, found 209.0 (M+1) +; Retention time: 1.22 minutes.1H NMR (400 MHz, DMSO-d6) δ 11.91 (s, 1H), 7.52 (d, J = 2.2 Hz, 1H), 5.69 (t, J = 2.3 Hz, 1H), 4.06 (s, 2H), 1.19 (s, 6H).

Step C: tert-Butyl 2,6-dichloropyridine-3-carboxylate (25)

[00160] A solution of 2,6-dichloropyridine-3-carboxylic acid (10 g, 52.08 mmol) in THF (210 mL) was treated successively with di-tert-butyl dicarbonate (17 g, 77.89 mmol) and 4-(dimethylamino)pyridine (3.2 g, 26.19 mmol) and left to stir overnight at room temperature. At this point, HCl 1N (400 mL) was added and the mixture was stirred vigorously for about 10 minutes. The product was extracted with ethyl acetate (2x300mL) and the combined organics layers were washed with water (300 mL) and brine (150 mL) and dried over sodium sulfate and concentrated under reduced pressure to give 12.94 g (96% yield) of tert-butyl 2,6-dichloropyridine-3-carboxylate as a colorless oil. ESI-MS m/z calc.247.01668, found 248.1 (M+1) +; Retention time: 2.27 minutes.1H NMR (300 MHz, CDCl3) ppm 1.60 (s, 9H), 7.30 (d, J=7.9 Hz, 1H), 8.05 (d, J=8.2 Hz, 1H).

Step D: tert-Butyl 2-chloro-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]pyridine-3-carboxylate (26)

[00161] To a solution of tert-butyl 2,6-dichloropyridine-3-carboxylate (10.4 g, 41.9 mmol) and 3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)-1H-pyrazole (9.0 g, 41.93 mmol) in DMF (110 mL) were added potassium carbonate (7.53 g, 54.5 mmol) and 1,4-diazabicyclo[2.2.2]octane (706 mg, 6.29 mmol) and the mixture was stirred at room temperature for 16 hours. The cream suspension was cooled in a cold water bath and cold water (130 mL) was slowly added. The thick suspension was stirred at room temperature for 1 hour, filtered and washed with plenty of water to give tert-butyl 2-chloro-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]pyridine-3-carboxylate (17.6 g, 99%) as an off white solid. ESI-MS m/z calc.419.12234, found 420.0 (M+1) +; Retention time: 2.36 minutes.1H NMR (400 MHz, DMSO-d6) δ 8.44 (d, J = 2.9 Hz, 1H), 8.31 (d, J = 8.4 Hz, 1H), 7.76 (d, J = 8.4 Hz, 1H), 6.26 (d, J = 2.9 Hz, 1H), 4.27 (s, 2H), 1.57 (s, 9H), 1.24 (s, 6H).

Step E: 2-chloro-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]pyridine-3-carboxylic acid (10)

[00162] tert-Butyl 2-chloro-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]pyridine-3-carboxylate (17.6 g, 40.25 mmol) was suspended in isopropanol (85 mL) treated with hydrochloric acid (34 mL of 6 M, 201 mmol) and heated to reflux for 3 hours (went almost complete into solution at reflux and started to precipitate again). The suspension was diluted with water (51 mL) at reflux and left to cool to room temperature under stirring for 2.5 h. The solid was collected by filtration, washed with

isopropanol/water 1:1 (50mL), plenty of water and dried in a drying cabinet under vacuum at 45-50 °C with a nitrogen bleed overnight to give 2-chloro-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]pyridine-3-carboxylic acid (13.7 g, 91%) as an off white solid. ESI-MS m/z calc.363.05975, found 364.0 (M+1) +; Retention time: 1.79 minutes. 1H NMR (400 MHz, DMSO-d6) δ 13.61 (s, 1H), 8.44 (d, J = 2.9 Hz, 1H), 8.39 (d, J = 8.4 Hz, 1H), 7.77 (d, J = 8.4 Hz, 1H), 6.25 (d, J = 2.9 Hz, 1H), 4.28 (s, 2H), 1.24 (s, 6H).

Step F: 2-Chloro-N-(1,3-dimethylpyrazol-4-yl)sulfonyl-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]pyridine-3-carboxamide (13)

[00163] 2-Chloro-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]pyridine-3-carboxylic acid (100 mg, 0.2667 mmol) and CDI (512 mg, 3.158 mmol) were combined in THF (582.0 µL) and the mixture was stirred at room temperature. Meanwhile, 1,3-dimethylpyrazole-4-sulfonyl chloride (62 mg, 0.3185 mmol) was combined with ammonia (in methanol) in a separate vial, instantly forming a white solid. After stirring for an additional 20 min, the volatiles were removed by evaporation, and 1 mL of dichloromethane was added to the solid residue, and was also evaporated. DBU (100 µL, 0.6687 mmol) was then added and the mixture stirred at 60 °C for 5 minutes, followed by addition of THF (1 mL) which was subsequently evaporated. The contents of the vial containing the CDI activated carboxylic acid in THF were then added to the vial containing the newly formed sulfonamide and DBU, and the reaction mixture was stirred for 4 hours at room temperature. The reaction mixture was diluted with 10 mL of ethyl acetate, and washed with 10 mL solution of citric acid (1 M). The aqueous layer was extracted with ethyl acetate (2x 10 mL) and the combined organics were washed with brine, dried over sodium sulfate, and concentrated to give 2-chloro-N-(1,3-dimethylpyrazol-4-yl)sulfonyl-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]pyridine-3-carboxamide as white solid (137 mg, 99%) that was used in the next step without further purification. ESI-MS m/z calc.520.09076, found 521.1 (M+1) +;

Retention time: 0.68 minutes.

Step G: N-(1,3-dimethylpyrazol-4-yl)sulfonyl-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]-2-[(4S)-2,2,4-trimethylpyrrolidin-1-yl]pyridine-3-carboxamide (Compound 1)

[00164] 2-Chloro-N-(1,3-dimethylpyrazol-4-yl)sulfonyl-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]pyridine-3-carboxamide (137 mg, 0.2630 mmol), (4S)-2,2,4-trimethylpyrrolidine (Hydrochloride salt) (118 mg, 0.7884 mmol), and potassium carbonate (219 mg, 1.585 mmol) were combined in DMSO (685.0 µL) and the mixture was heated at 130 ^C for 16 hours. The reaction was cooled to room temperature, and 1 mL of water was added. After stirring for 15 minutes, the contents of the vial were allowed to settle, and the liquid portion was removed via pipet and the remaining solids were dissolved with 20 mL of ethyl acetate and were washed with 1 M citric acid (15 mL). The layers were separated and the aqueous layer was extracted two additional times with 15 mL of ethyl acetate. The organics were combined, washed with brine, dried over sodium sulfate and concentrated. The resulting solid was further purified by silica gel chromatography eluting with a gradient of methanol in dichloromethane (0-10%) to give N-(1,3-dimethylpyrazol-4-yl)sulfonyl-6-[3-(3,3,3-trifluoro-2,2-dimethyl-propoxy)pyrazol-1-yl]-2-[(4S)-2,2,4-trimethylpyrrolidin-1-yl]pyridine-3-carboxamide (72 mg, 41%) as a white solid. ESI-MS m/z calc.597.2345, found 598.3 (M+1) +; Retention time: 2.1 minutes.1H NMR (400 MHz, DMSO) δ 12.36 (s, 1H), 8.37 (s, 1H), 8.22 (d, J = 2.8 Hz, 1H), 7.74 (d, J = 8.2 Hz, 1H), 6.93 (d, J = 8.2 Hz, 1H), 6.17 (d, J = 2.8 Hz, 1H), 4.23 (s, 2H), 3.81 (s, 3H), 2.56 (d, J = 10.4 Hz, 1H), 2.41 (t, J = 8.7 Hz, 1H), 2.32 (s, 3H), 2.18 (dd, J = 12.4, 6.1 Hz, 1H), 1.87 (dd, J = 11.7, 5.5 Hz, 1H), 1.55 (d, J = 11.2 Hz, 6H), 1.42 (t, J = 12.0 Hz, 1H), 1.23 (s, 6H), 0.81 (d, J = 6.2 Hz, 3H).

///////////VX-445, Elexacaftor, VX445, エレクサカフトル  , PHASE 3, CYSTIC FIBRIOSIS, VX 445

C[C@@H]1CN(c2nc(ccc2C(=O)NS(=O)(=O)c3cn(C)nc3C)n4ccc(OCC(C)(C)C(F)(F)F)n4)C(C)(C)C1

CC1CC(N(C1)C2=C(C=CC(=N2)N3C=CC(=N3)OCC(C)(C)C(F)(F)F)C(=O)NS(=O)(=O)C4=CN(N=C4C)C)(C)C

MITAPIVAT


Structure of MITAPIVAT

Mitapivat

MITAPIVAT

CAS 1260075-17-9

MF C24H26N4O3S
MW 450.55

8-Quinolinesulfonamide, N-[4-[[4-(cyclopropylmethyl)-1-piperazinyl]carbonyl]phenyl]-

N-[4-[[4-(Cyclopropylmethyl)-1-piperazinyl]carbonyl]phenyl]-8-quinolinesulfonamide

  • Originator Agios Pharmaceuticals
  • Class Antianaemics; Piperazines; Quinolines; Small molecules; Sulfonamides
  • Mechanism of Action Pyruvate kinase stimulants
  • Orphan Drug Status Yes – Inborn error metabolic disorders
  • New Molecular Entity Yes
  • Phase III Inborn error metabolic disorders
  • Phase II  Thalassaemia
  • 27 Feb 2019 Agios Pharmaceuticals plans a phase III trial for Inborn error metabolic disorders (Pyruvate kinase deficiency) (Treatment-experienced) in the US, Brazil, Canada, Czech Republic, Denmark, France, Germany, Ireland, Italy, Japan, South Korea, Netherlands, Portugal, Spain, Switzerland, Thailand, Turkey and United Kingdom in March 2019 (NCT03853798) (EudraCT2018-003459-39)
  • 11 Dec 2018 Phase-II clinical trials in Thalassaemia in Canada (PO) (NCT03692052)
  • 29 Aug 2018 Chemical structure information added

Activator of pyruvate kinase isoenzyme M2 (PKM2), an enzyme involved in glycolysis. Since all tumor cells exclusively express the embryonic M2 isoform of PK, it is hypothesized that PKM2 is a potential target for cancer therapy. Modulation of PKM2 might also be effective in the treatment of obesity, diabetes, autoimmune conditions, and antiproliferation-dependent diseases.

Agios Pharmaceuticals is developing AG-348 (in phase 3 , in June 2019), an oral small-molecule allosteric activator of the red blood cell-specific form of pyruvate kinase (PK-R), for treating PK deficiency and non-transfusion-dependent thalassemia.

SYN

WO 20100331307

str1

CAS 59878-57-8 TO CAS 57184-25-5

Eisai Co., Ltd., EP1508570,  Lithium aluminium hydride (770 mg, 20.3 mmol) was suspended in tetrahydrofuran (150 mL), 1-(cyclopropylcarbonyl)piperazine (1.56 g, 10.1 mmol) was gradually added thereto, and the reaction mixture was heated under reflux for 30 minutes. The reaction mixture was cooled to room temperature, and 0.8 mL of water, 0.8 mL of a 15percent aqueous solution of sodium hydroxide and 2.3 mL of water were seque ntially gradually added thereto. The precipitated insoluble matter was removed by filtration through Celite, and the filtrate was evaporated to give the title compound (1.40g) as a colorless oil. The product was used for the synthesis of (8E,12E,14E)-7-((4-cyclopropylmethylpiperazin-1-yl)carbonyl)oxy-3,6,16,21-tetrahydroxy-6,10,12,16,20-pentamethyl-18,19-epoxytricosa-8,12,14-trien-11-olide (the co mpound of Example 27) without further purification.1H-NMR Spectrum (CDCl3,400MHz) delta(ppm): 0.09-0.15(2H,m), 0.48-0.56(2H,m),0.82-0.93(1H,m),2.25(2H,d,J=7.2Hz) 2.48-2.65(4H,m),2.90-2.99(4H,m).

str1

CAS 91-22-5 TO CAD 18704-37-5

chlorosulfonic acid;

Russian Journal of Organic Chemistry, vol. 36, 6, (2000), p. 851 – 853

Yield : 52%1-Step Reaction

NMR

US2010/331307

dimethylsulfoxide-d6, 1H

1H NMR (400 MHz, DMSO-d6) δ: 1.2 (t, 2H), 1.3 (t, 2H), 1.31-1.35 (m, 1H), 2.40 (s, 2H), 3.68 (br s, 4H), 3.4-3.6 (m, 4H), 7.06 (m, 6H), 7.25-7.42 (m, 3H), 9.18 (s, 1H) 10.4 (s, 1H)

1H NMR (400 MHz, DMSO-d6) δ: 0.04-0.45 (m, 2H), 0.61-0.66 (m, 2H), 1.4-1.6 (m, 1H), 2.21-2.38 (m, 4H), 2.61 (d, 2H), 3.31-3.61 (br s, 4H), 6.94-7.06 (m, 4H), 7.40 (d, 2H), 7.56-7.63 (m, 2H), 8.28 (d, 1H), 9.18 (s, 1H), 10.4 (s, 1H)

Development Overview

Introduction

Mitapivat (designated AG 348), an orally available, first-in-class, small molecule stimulator of pyruvate kinase (PK), is being developed by Agios Pharmaceuticals for the treatment of pyruvate kinase deficiency (Inborn error metabolic disorders in development table) and thalassemia. Mitapivat is designed to activate the wild-type (normal) and mutated PK-R (the isoform of pyruvate kinase that is present in erythrocytes), in order to correct the defects in red cell glycolysis found within mutant cells. Clinical development is underway for inborn error metabolic disorders in the US, Spain and Denmark and for Thalassaemia in Canada.

Mitapivat emerged from Agios’ research programme focussed on the discovery of small molecule therapeutics for inborn metabolic disorders [see Adis Insight Drug Profile 800036791].

Key Development Milestones

In April 2017, the US FDA granted fast track designation to mitapivat for the treatment of pyruvate kinase deficiency 

In June 2018, Agios Pharmaceuticals initiated the phase III ACTIVATE trial to evaluate the efficacy and safety of orally administered mitapivat as compared with placebo in participants with pyruvate kinase deficiency (PKD), who are not regularly receiving blood transfusions (NCT03548220; AG348-C-006). The randomised, double-blind, placebo-controlled global trial intends to enrol 80 patients in the US, Canada, Denmark, France, Germany, Italy, Japan, South Korea, Netherlands, Poland, Portugal, Spain, Switzerland, Thailand and United Kingdom. The study design has two parts. Part 1 is a dose optimisation period where patients start at 5mg of mitapivat or placebo twice daily, with the flexibility to titrate up to 20mg or 50mg twice daily over a three month period to establish their individual optimal dose, as measured by maximum increase in hemoglobin levels. After the dose optimisation period, patients will receive their optimal dose for an additional three months in part 2. The primary endpoint of the study is the proportion of patients who achieve at least a 1.5 g/dL increase in haemoglobin sustained over multiple visits in part 2 of the trial 

In February 2018, Agios Pharmaceuticals initiated the phase III ACTIVATE-T trial to assess the efficacy and safety of mitapivat in regularly transfused adult subjects with pyruvate kinase deficiency (Inborn error metabolism disorders in development table) (EudraCT2017-003803-22; AG348-C-007). The open label trial will enrol approximately 20 patients in Denmark and Spain and will expand to Canada, France, Italy, Japan, the Netherlands, the UK and the US 

In December 2018, Agios Pharmaceuticals initiated a phase II study to assess the safety, efficacy, pharmacokinetics and pharmacodynamics of mitapivat (50mg and 100mg) for the treatment of patients with non-transfusion-dependent thalassemia (AG348-C-010; EudraCT2018-002217-35; NCT03692052). This study will include a 24-week core period followed by a 2-year extension period for eligible participants. The open-label trial intends to enrol approximately 17 patients. Enrolment has been initiated in Canada and may expand to the US and the UK 

Agios Pharmaceuticals, in June 2015 initiated the phase II DRIVE PK trial to evaluate the safety, efficacy, pharmacokinetics and pharmacodynamics of mitapivat in adult transfusion-independent patients with pyruvate kinase deficiency (Inborn error metabolism disorders in development table) (AG348-C-003; NCT02476916). The trial will include two arms with 25 patients each. The patients in the first arm will receive 50mg twice daily, and the patients in the second arm will receive 300mg twice daily. The study will include a six-month dosing period with the opportunity for continued treatment beyond six months based on safety and clinical activity. The open-label, randomised trial completed enrolment of targeted 52 patients in the US, in November 2016. Preliminary data from the trial was presented at the 21st Congress of the European Haematology Association (EHA-2016). Updated results were presented by Agios at the 58th Annual Meeting and Exposition of the American Society of Haematology in December 2016. Based on results of the DRIVE PK trial, Agios plans to develop a registration path for mitapivat. Updated data from the trial was presented at the 22nd Congress of the European Haematology Association (EHA-2017) 

In December 2017, Agios pharmaceuticals presented updated safety and efficacy data from this trial at the 59th Annual Meeting and Exposition of the American Society of Hematology (ASH- Hem 2017). Results showed that chronic daily dosing with mitapivat has been well tolerated and has resulted in clinically relevant, durable increases in Hb and reductions in markers of haemolysis across a range of doses 

In June 2018, Agios Pharmaceuticals completed a phase I trial in healthy male volunteers to assess the absorption, distribution, metabolism, excretion and absolute bioavailability of AG 348 (AG348-C-009; NCT03703505). Radiolabelled analytes of AG 348 ([14C]AG 348 and [13C6]AG 348) were administered in a single oral and intravenous dose on day 1. The open label trial was initiated in May 2018 and enrolled 8 volunteers in the US 

In November 2017, Agios Pharmaceuticals completed a phase I trial that evaluated the relative bioavailability and safety of the mitapivat tablet and capsule formulations after single-dose administration in healthy adults (AG348-C-005; NCT03397329). The open-label trial enrolled 26 subjects in the US and was initiated in October 2017 

In October 2017, Agios Pharmaceuticals completed a phase I trial that evaluated the pharmacokinetics, safety and effect on QTc interval of mitapivat in healthy volunteers (AG348-C-004; NCT03250598). This single-dose, open-label trial was initiated in August 2017 and enrolled 60 volunteers in the US

In November 2014, Agios completed a randomised, double-blind, placebo-controlled phase I trial that assessed the safety, pharmacokinetics and pharmacodynamics of multiple escalating doses of mitapivat in healthy volunteers (MAD; AG-348MAD; AG348-C-002; NCT02149966). Mitapivat was dosed daily for 14 days. The trial recruited 48 subjects in the US. In June 2015, positive results from the trial were presented at the 20th congress of the European Haematology Association (EHA-2015). Mitapivat showed a favourable pharmacokinetic profile with rapid absorption, low to moderate variability and a dose-proportional increase in exposure following multiple doses and serum hormone changes consistent with reversible aromatase inhibition were also observed 

Agios Pharmaceuticals completed a randomised, double-blind, placebo-controlled phase I clinical trial of mitapivat in August 2014 (AG-348 SAD; AG348-C-001; NCT02108106). The study evaluated the safety, pharmacokinetics and pharmacodynamics of single escalating doses of the agent in healthy volunteers. Potential metabolic biomarkers were also explored. The trial enrolled 48 participants in the US 

IND-enabling studies were conducted in 2013 In December 2013, Agios presented data from in vitro studies at the 55th Annual Meeting and Exposition of the American Society of Hematology (ASH-Hem-2013), showing that mitapivat activates a range of pyruvate kinase mutant proteins in blood samples taken from patients with pyruvate kinase deficiency. The company hypothesised that mitapivat may restore the glycolytic pathway activity and normalise erythrocyte metabolism in vivo The US FDA granted orphan designation for mitapivat for the treatment of pyruvate kinase deficiency. The designation was granted to Agios Pharmaceuticals, in March 2015.

Patent Information

As of January 2018, Agios Pharmaceuticals owned approximately six issued US patents, 65 issued foreign patents, five pending US patent applications and 55 pending foreign patent applications in a number of jurisdictions directed to PK deficiency programme, including mitapivat (AG 348). The patents are valid till at least 2030 

Patents

US 20100331307 A1
WO 2011002817 A1
WO 2012151451 A1
WO 2013056153 A1
WO 2014018851 A1
WO 2016201227 A1

WO2011002817

Mitapivat, also known as PKM2 activator 1020, is an activator of a pyruvate kinase PKM2, an enzyme involved in glycolysis. It was disclosed in a patent publication WO 2011002817 A1 as compound 78.

WO2019099651 ,

PATENT

WO-2019104134

Novel crystalline and amorphous forms of N-(4-(4-(cyclopropylmethyl)piperazine-1-carbonyl)phenyl)quinoline-8-sulfonamide (also known as mitapivat ) and their hemi-sulfate, solvates, hydrates, sesquihydrate, anhydrous and ethanol solvate (designated as Form A-J), processes for their preparation and compositions comprising them are claimed. Also claims are their use for treating pyruvate kinase deficiency, such as sickle cell disease, thalassemia and hemolytic anemia.

Pyruvate kinase deficiency (PKD) is a disease of the red blood cells caused by a deficiency of the pyruvate kinase R (PKR) enzyme due to recessive mutations of PKLR gene (Wijk et al. Human Mutation, 2008, 30 (3) 446-453). PKR activators can be beneficial to treat PKD, thalassemia (e.g., beta-thalessemia), abetalipoproteinemia or Bassen-Kornzweig syndrome, sickle cell disease, paroxysmal nocturnal hemoglobinuria, anemia (e.g., congenital anemias (e.g., enzymopathies), hemolytic anemia (e.g. hereditary and/or congenital hemolytic anemia, acquired hemolytic anemia, chronic hemolytic anemia caused by phosphoglycerate kinase deficiency, anemia of chronic diseases, non- spherocytic hemolytic anemia or hereditary spherocytosis). Treatment of PKD is supportive, including blood transfusions, splenectomy, chelation therapy to address iron overload, and/or interventions for other disease-related morbidity. Currently, however, there is no approved medicine that treats the underlying cause of PKD, and thus the etiology of life-long hemolytic anemia.

[0003] N-(4-(4-(cyclopropylmethyl)piperazine-l-carbonyl)phenyl)quinoline-8-sulfonamide, herein referred to as Compound 1, is an allosteric activator of red cell isoform of pyruvate kinase (PKR). See e.g., WO 2011/002817 and WO 2016/201227, the contents of which are incorporated herein by reference.


(Compound 1)

[0004] Compound 1 was developed to treat PKD and is currently being investigated in phase 2 clinical trials. See e.g., U.S. clinical trials identifier NCT02476916. Given its therapeutic benefits, there is a need to develo

Compound 1, i.e., the non-crystalline free base, can be prepared following the procedures described below.

Preparation of ethyl -4-(quinoline-8-sulfonamido) benzoate

EtO TV 

[00170] A solution containing ethyl-4-aminobenzoate (16. Og, 97mmol) and pyridine (l4.0g, l77mmol) in acetonitrile (55mL) was added over 1.2 hours to a stirred suspension of quinoline- 8 -sulfonyl chloride (20.0g, 88mmol) in anhydrous acetonitrile (100 mL) at 65°C. The mixture was stirred for 3.5 hours at 65 °C, cooled to 20°C over 1.5 hours and held until water (140 mL) was added over 1 hour. Solids were recovered by filtration, washed 2 times (lOOmL each) with acetonitrile/water (40/60 wt./wt.) and dried to constant weight in a vacuum oven at 85°C. Analyses of the white solid (30.8g, 87mmol) found (A) HPLC purity = 99.4% ethyl -4-(quinoline-8-sulfonamido) benzoate, (B) LC-MS consistent with structure, (M+l)= 357 (C18 column eluting 95-5, CH3CN/water, modified with formic acid, over 2 minutes), and (C) 1H NMR consistent with structure (400 MHz, DMSO-i 6) = d 10.71 (s, 1H), 9.09 (dd, 7 = 4.3, 1.6 Hz, 1H), 8.46 (ddt, 7 = 15.1, 7.3, 1.5 Hz, 2H), 8.26 (dd, 7 = 8.3, 1.4 Hz, 1H), 7.84 – 7.54 (m, 4H), 7.18 (dd, 7 = 8.6, 1.3 Hz, 2H), 4.26 – 4.07 (m, 2H), 1.19 (td, 7 = 7.1, 1.2 Hz, 3H).

Preparation of 4-(quinoline-8-sulfonamide) benzoic acid

Step 2

[00171] A NaOH solution (16.2g, l22mmol) was added over 30 minutes to a stirred suspension of ethyl -4-(quinoline-8-sulfonamido) benzoate (20. Og, 56.2mmol) in water (125 mL) at 75°C. The mixture was stirred at 75°-80°C for 3 hours, cooled 20°C and held until THF (150 mL) was added. Hydrochloric acid (11% HCL, 8lmL, l32mmol) was added over >1 hour to the pH of 3.0. The solids were recovered by filtration at 5°C, washed with water (2X lOOmL) and dried to constant weight in a vacuum oven at 85°C. Analysis of the white solid (16.7g, 51 mmol) found (A) HPLC puurity = >99.9% 4-(quinoline-8-sulfonamide)benzoic acid, LC-MS consistent with structure (M+l) = 329 (Cl 8 column eluting 95-5 CH3CN/water, modified with formic acid, over 2 minutes.) and 1H NMR consistent with structure (400 MHz, DMSO-76) = d 12.60 (s, 1H), 10.67 (s, 1H), 9.09 (dd, 7 = 4.2, 1.7 Hz, 1H), 8.46 (ddt, 7 = 13.1, 7.3, 1.5 Hz, 2H), 8.26 (dd, 7 = 8.2, 1.5 Hz, 1H), 7.77 -7.62 (m, 3H), 7.64 (d, 7 = 1.3 Hz, 1H), 7.16 (dd, 7 = 8.7, 1.4 Hz, 2H).

Preparation of l-(cyclopropylmethyl)piperazine dihydrochloride (4)

1 ) NaBH(OAc)3

2 3 acetone 4

[00172] To a 1 L reactor under N2 was charged tert-butyl piperazine- l-carboxylate (2) (100.0 g, 536.9 mmol), cyclopropanecarbaldehyde (3) (41.4 g, 590.7 mmol ), toluene (500.0 mL) and 2-propanol (50.0 mL). To the obtained solution was added NaBH(OAc)3 (136.6 g, 644.5 mmol) in portions at 25-35 °C and the mixture was stirred at 25 °C for 2 h. Water (300.0 mL) was added followed by NaOH solution (30%, 225.0 mL) to the pH of 12. The layers were separated and the organic layer was washed with water (100.0 mLx2). To the organic layer was added hydrochloric acid (37%, 135.0 mL, 1.62 mol) and the mixture was stirred at 25 °C for 6 h. The layers were separated and the aqueous layer was added to acetone (2.0 L) at 25 °C in lh. The resulted suspension was cooled to 0 °C. The solid was filtered at 0 °C, washed with acetone (100.0 mLx2) and dried to afford 4 (105.0 g) in 92% isolated yield. LC-MS (C18 column eluting 90-10 CH3CN/water over 2 minutes) found (M+l) =141. 1H NMR (400 MHz, DMSO-76) d 11.93 (br.s, 1H), 10.08 (br., 2H), 3.65 (br.s, 2H), 3.46 (br.s, 6H), 3.04 (d, / = 7.3 Hz, 2H), 1.14 – 1.04 (m, 1H), 0.65 – 0.54 (m, 2H), 0.45 – 0.34 (m, 2H) ppm.

Preparation of N-(4-(4-(cyclopropylmethyl)piperazine-l-carbonyl)phenyl)quinoline-8- sulfonamide (1)

[00173] To a 2 L reactor under N2 was charged 4-(quinoline-8-sulfonamido) benzoic acid (5) (100.0 g, 304.5 mmol) and DMA (500.0 mL). To the resulted suspension was added CDI (74.0 g, 456.4 mmol) in portions at 25 °C and the mixture was stirred at 25 °C for 2 h. To the resulted suspension was added l-(cyclopropylmethyl)piperazine dihydrochloride (4) (97.4 g, 457.0 mmol) in one portion at 25 °C and the mixture was stirred at 25 °C for 4 h. Water (1.0 L) was added in 2 h. The solid was filtered at 25 °C, washed with water and dried under vacuum at 65 °C to afford 1 (124.0 g) in 90 % isolated yield. LC-MS (C18 column eluting 90-10 CH3CN/water over 2 minutes) found (M+l) =451. 1H NMR (400 MHz, DMSO-76) d

10.40 (br.s, 1H), 9.11 (dd, 7 = 4.3, 1.6 Hz, 1H), 8.48 (dd, / = 8.4, 1.7 Hz, 1H), 8.40 (dt, /

7.4, 1.1 Hz, 1H), 8.25 (dd, 7 = 8.3, 1.3 Hz, 1H), 7.76 – 7.63 (m, 2H), 7.17 – 7.05 (m, 4H), 3.57 – 3.06 (m, 4H), 2.44 – 2.23 (m, 4H), 2.13 (d, J = 6.6 Hz, 2H), 0.79 – 0.72 (m, 1H), 0.45 – 0.34 (m, 2H), 0.07 – 0.01 (m, 2H) ppm.

[00174] Two impurities are also identified from this step of synthesis. The first impurity is Compound IM- 1 (about 0.11% area percent based on representative HPLC) with the following structure:


Compound IM-l)

Compound IM-l was generated due to the presence of N-methyl piperazine, an impurity in compound 2, and was carried along to react with compound 5. LC-MS found (M+l) =411.2;

(M-l)= 409.2. 1H NMR (400 MHz, DMSO-76) d 10.43 (brs, 1H) 9.13-9.12 (m, 1H), 8.52-8.50 (m, 1H), 8.43-8.41 (m, 1H), 8.26 (d, 7=4.0 Hz, 1 H), 7.73-7.70 (m, 2H), 7.15-7.097.69 (m, 4H), 3.60-3.25 (brs, 4H), 2.21 (brs, 4H), 2.13 (s, 3H).

[00175] The second impurity is Compound IM-2 (about 0.07% area percent based on the representative HPLC) with the following structure:


(Compound IM-2)

Compound IM-2 was due to the presence of piperazine, an impurity generated by

deprotection of compound 2. The piperazine residue was carried along to react with two molecules of compound 5 to give Compound IM-2. LC-MS found (M+l) =707. 1H NMR (400 MHz, CF3COOD) d 9.30-9.23 (m, 4H), 8.51 (s, 4H), 8.20-8.00 (m, 4H), 7.38-7.28 (m, 8H), 4.02-3.54 (m, 8H).

Solubility Experiments

[00176] Solubility measurements were done by gravimetric method in 20 different solvents at two temperatures (23 °C and 50 °C). About 20-30 mg of Form A, the synthesis of which is described below, was weighed and 0.75 mL solvent was added to form a slurry. The slurry was then stirred for two days at the specified temperature. The vial was centrifuged and the supernatant was collected for solubility measurement through gravimetric method. The saturated supernatant was transferred into pre- weighed 2 mL HPLC vials and weighed again (vial + liquid). The uncapped vial was then left on a 50 °C hot plate to slowly evaporate the solvent overnight. The vials were then left in the oven at 50 °C and under vacuum to remove the residual solvent so that only the dissolved solid remained. The vial was then weighed (vial + solid). From these three weights; vial, vial+liquid and vial+solid; the weight of dissolved solid and the solvent were calculated. Then using solvent density the solubility was calculated as mg solid/mL of solvent. Solubility data are summarized in Table 1.

Table 1

Optimized Crystalline Form A Hemisulfate Salt Scale-up Procedure

[00202] An optimized preparation of Form A as a hemisulfate sesquihydrate salt with and without seeding is provided below.

Preparation of l-(cyclopropylmethyl)-4-(4-(quinoline-8-sulfonamido)benzoyl)piperazin- 1-ium sulfate trihydrate (Form A) with seeding

[00203] To a 2 L reactor under N2 was charged N-(4-(4-(cyclopropylmethyl)piperazine-l-carbonyl)phenyl)quinoline-8-sulfonamide (5) (111.0 g, 246.4 mmol), and a pre-mixed process solvent of ethanol (638.6 g), toluene (266.1 g) and water (159.6 g). The suspension was stirred and heated above 60°C to dissolve the solids, and then the resulting solution was cooled to 50°C. To the solution was added an aqueous solution of H2S04 (2.4 M, 14.1 mL, 33.8 mmol), followed by l-(cyclopropylmethyl)-4-(4-(quinoline-8-sulfonamido)benzoyl)piperazin-l-ium sulfate trihydrate (6) (1.1 g, 2.1 mmol). After 1 h stirring, to the suspension was added an aqueous solution of H2S04 (2.4 M, 42.3 mL, 101.5 mmol) over 5 h. The suspension was cooled to 22°C and stirred for 8 h. The solids were filtered at 22°C, washed with fresh process solvent (2 x 175 g) and dried to give the product (121.6 g) in 94% isolated yield. LC-MS (C18 column eluting 90-10 CH3CN/water over 2 minutes) found (M+l) = 451. 1H NMR (400 MHz, DMSO-76) d 10.45 (s, 1H), 9.11 (dd, J =

4.2, 1.7 Hz, 1H), 8.50 (dd, 7 = 8.4, 1.7 Hz, 1H), 8.41 (dd, 7 = 7.3, 1.5 Hz, 1H), 8.27 (dd, 7 8.2, 1.5 Hz, 1H), 7.79 – 7.60 (m, 2H), 7.17 (d, / = 8.4 Hz, 2H), 7.11 (d, J = 8.4 Hz, 2H), 3.44 (d, J = 8.9 Hz, 5H), 3.03 – 2.50 (m, 6H), 0.88 (p, J = 6.3 Hz, 1H), 0.50 (d, J = 7.6 Hz, 2H), 0.17 (d, 7 = 4.9 Hz, 2H).

Preparation of l-(cyclopropylmethyl)-4-(4-(quinoline-8-sulfonamido)benzoyl)piperazin- 1-ium sulfate trihydrate (Form A) without seeding

[00204] To a 50 L reactor was charged N-(4-(4-(cyclopropylmethyl)piperazine-l-carbonyl)phenyl)quinoline-8-sulfonamide (5) (1.20 kg, 2.66 mol) and water (23.23 L) at 28°C. While stirring the suspension, an aqueous solution of H2S04 (1.0 M, 261 g) was added dropwise over 2 h. The reaction was stirred at 25 – 30°C for 24 h. The solids were filtered and dried under vacuum below 30°C for 96 h to give the product (1.26 kg) in 90% isolated yield.

11. Reproduction and Preparation of Various Patterns

[00205] The patterns observed during the previous experiments were reproduced for characterization. Patterns B, D, E, F were reproducible. Pattern G was reproduced at lower crystallinity. Pattern I was reproduced, although, it was missing a few peaks. Refer to Table 20.

Table 20

Crystalline Free Base Form of Compound 1

[00215] The crystalline free-base form of Compound 1 can be prepared via the following method.

[00216] 14.8 kg S-l and 120 kg DMAc are charged into a round bottom under N2 protection and the reaction is stirred at 30 °C under N2 protection for 40min, to obtain a clear yellow solution. 7.5 kg CDI (1.02 eq.) is added and the reaction is stirred at 30 °C for 2.5h under N2 protection. 0.6 kg of CDI (0.08 eq.) at 30 °C was added and the mixture was stirred at 30 °C for 2h under N2 protection. The reaction was tested again for material consumption. 11.0 kg (1.14 eq.) l-(cyclopropylmethyl)piperazine chloride was charged in the round bottom at 30 °C and the reaction was stirred under N2 protection for 6h (clear solution). 7.5 X H20 was added dropwise over 2h, some solid formed and the reaction was stirred for lh at 30 °C. 16.8 X H20 was added over 2.5h and the reaction was stirred stir for 2.5h. 3.8 kg (0.25 X) NaOH (30%, w / w, 0.6 eq.) was added and the reaction was stirred for 3h at 30 °C. The reaction was filtered and the wet cake was rinsed with H20 / DMAc=44 kg / 15 kg. 23.35 kg wet cake was obtained (KF: 4%). The sample was re-crystallized by adding 10.0 X DMAc and stirred for lh at 70 °C, clear solution; 4.7 X H20 was added over 2h at 70 °C and the reaction was stirred 2h at 70 °C; 12.8 X H20 was added dropwise over 3h and stirred for 2h at 70 °C; the reaction was adjusted to 30 °C over 5h and stirred for 2h at 30 °C; the reaction was filtered and the wet cake was rinsed with DMAc / H20=l5 kg / 29 kg and 150 kg H20. 19.2 kg wet cake was obtained. The material was recrystallized again as follows. To the wet cake was added 10.0 X DMAc and the reaction was stirred for lh at 70 °C, clear solution.

16.4 X H20 was added dropwise at 70 °C and the reaction was stirred for 2h at 70 °C. The reaction was adjusted to 30 °C over 5.5h and stirred for 2h at 30 °C. The reaction was centrifuged and 21.75 kg wet cake was obtained. The material was dried under vacuum at 70°C for 25h. 16.55 kg of the crystalline free base form of compound 1 was obtained. Purity of 99.6%.

C Kung. Activators of pyruvate kinase M2 and methods of treating disease. PCT Int. Appl. WO 2013056153 A1. 
FG Salituro et al. Preparation of aroylpiperazines and related compounds as pyruvate kinase M2 modulators useful in treatment of cancer. U.S. Pat. Appl. US 20100331307 A1. 

Drug Properties & Chemical Synopsis

  • Route of administrationPO
  • FormulationTablet, unspecified
  • ClassAntianaemics, Piperazines, Quinolines, Small molecules, Sulfonamides
  • Mechanism of ActionPyruvate kinase stimulants
  • WHO ATC codeA16A-X (Various alimentary tract and metabolism products)B03 (Antianemic Preparations)B06A (Other Hematological Agents)
  • EPhMRA codeA16A (Other Alimentary Tract and Metabolism Products)B3 (Anti-Anaemic Preparations)B6 (All Other Haematological Agents)
  • Chemical nameN-[4-[4-(cyclopropylmethyl)piperazine-1-carbonyl]phenyl]quinoline-8-sulfonamide
  • Molecular formulaC24 H26 N4 O3 S

References

  1. Agios Reports First Quarter 2017 Financial Results.

    Media Release 

  2. Agios Announces Initiation of Global Phase 3 Trial (ACTIVATE) of AG-348 in Adults with Pyruvate Kinase Deficiency Who Are Not Regularly Transfused.

    Media Release 

  3. A Phase 3, Randomized, Double-Blind, Placebo-Controlled Study to Evaluate the Efficacy and Safety of AG-348 in Not Regularly Transfused Adult Subjects With Pyruvate Kinase Deficiency

    ctiprofile 

  4. Agios Provides Business Update on Discovery Research Strategy and Pipeline, Progress on Clinical Programs, Commercial Launch Preparations and Reports First Quarter 2018 Financial Results at Investor Day.

    Media Release 

  5. An Open-Label Study To Evaluate the Efficacy and Safety of AG-348 in Regularly Transfused Adult Subjects With Pyruvate Kinase (PK) Deficiency

    ctiprofile 

  6. A Phase 2, Open-label, Multicenter Study to Determine the Efficacy, Safety, Pharmacokinetics, and Pharmacodynamics of AG-348 in Adult Subjects With Non-transfusion-dependent Thalassemia

    ctiprofile 

  7. Agios Announces Key Upcoming Milestones to Support Evolution to a Commercial Stage Biopharmaceutical Company in 2017.

    Media Release 

  8. Agios to Present Clinical and Preclinical Data at the 20th Congress of the European Hematology Association.

    Media Release 

  9. Agios Announces Updated Data from Fully Enrolled DRIVE PK Study Demonstrating AG-348s Potential as the First Disease-modifying Treatment for Patients with Pyruvate Kinase Deficiency.

    Media Release 

  10. Agios Announces New Data from AG-348 and AG-519 Demonstrating Potential for First Disease-modifying Treatment for Patients with PK Deficiency.

    Media Release 

  11. Agios Provides Update on PKR Program.

    Media Release 

  12. AG-348 Achieves Proof-of-Concept in Ongoing Phase 2 DRIVE-PK Study and Demonstrates Rapid and Sustained Hemoglobin Increases in Adults with Pyruvate Kinase Deficiency.

    Media Release 

  13. Agios Reports New, Final Data from Phase 1 Multiple Ascending Dose (MAD) Study in Healthy Volunteers for AG-348, an Investigational Medicine for Pyruvate Kinase (PK) Deficiency.

    Media Release 

  14. Grace RF, Layton DM, Galacteros F, Rose C, Barcellini W, Morton DH, et al. Results Update from the DRIVE PK Study: Effects of AG-348, a Pyruvate Kinase Activator, in Patients with Pyruvate Kinase Deficiency. ASH-Hem-2017 2017; abstr. 2194.

    Available from: URL: https://ash.confex.com/ash/2017/webprogram/Paper102236.html

  15. A Phase 2, Open Label, Randomized, Dose Ranging, Safety, Efficacy, Pharmacokinetic and Pharmacodynamic Study of AG-348 in Adult Patients With Pyruvate Kinase Deficiency

    ctiprofile 

  16. A Phase I, Open-label Study to Evaluate the Absorption, Distribution, Metabolism, and Excretion and to Assess the Absolute Bioavailability of AG-348 in Healthy Male Subjects Following Administration of a Single Oral Dose of [14C]AG-348 and Concomitant Single Intravenous Microdose of [13C6]AG-348

    ctiprofile 

  17. A Phase 1, Randomized, Open-Label, Two-Period Crossover Study Evaluating the Relative Bioavailability and Safety of the AG-348 Tablet and Capsule Formulations After Single-Dose Administration in Healthy Adults

    ctiprofile 

  18. A Phase 1, Single-Dose, Open-Label Study to Characterize and Compare the Pharmacokinetics, Safety, and Effect on QTc Interval of AG-348 in Healthy Subjects of Japanese Origin and Healthy Subjects of Non-Asian Origin

    ctiprofile 

  19. Agios Pharmaceuticals Initiates Multiple Ascending Dose Trial in Healthy Volunteers of AG-348 for the Potential Treatment of PK Deficiency, a Rare, Hemolytic Anemia.

    Media Release 

  20. A Phase 1, Randomized, Double-Blind, Placebo-Controlled, Multiple Ascending Dose, Safety, Pharmacokinetic, and Pharmacodynamic Study of Orally Administered AG-348 in Healthy Volunteers

    ctiprofile 

  21. Agios Initiates Phase 1 Study of AG-348, a First-in-class PKR Activator, for Pyruvate Kinase Deficiency.

    Media Release 

  22. A Phase I, Randomized, Double-Blind, Placebo-Controlled, Single Ascending Dose, Safety, Pharmacokinetic and Pharmacodynamic Study of Orally Administered AG-348 in Healthy Volunteers

    ctiprofile 

  23. Agios Pharmaceuticals Reports First Quarter 2014 Financial Results.

    Media Release 

  24. Agios Pharmaceuticals Reports Third Quarter 2013 Financial Results.

    Media Release 

  25. Agios Pharmaceuticals to Present Preclinical Research at the 2013 American Society of Hematology Annual Meeting.

    Media Release 

  26. Agios Presents Preclinical Data from Lead Programs at American Society of Hematology Annual Meeting.

    Media Release 

  27. Agios Pharmaceuticals Form 10-K, February 2018. Internet-Doc 2018;.

    Available from: URL: https://www.sec.gov/Archives/edgar/data/1439222/000143922218000004/agio-123117x10k.htm

  28. Agios Outlines Key 2018 Priorities Expanding Clinical and Research Programs to Drive Long Term Value.

    Media Release 

  29. Grace RF, Layton DM, Galacteros F, Rose C, Barcellini W, Morton DH, et al. Effects of Ag-348, a Pyruvate Kinase Activator, in Patients with Pyruvate Kinase Deficiency: Updated Results from the Drive Pk Study. EHA-2017 2017; abstr. S451.

    Available from: URL: https://learningcenter.ehaweb.org/eha/2017/22nd/181738/rachael.f.grace.effects.of.ag-348.a.pyruvate.kinase.activator.in.patients.with.html?f=m3e1181l15534

  30. Agios Presents Updated Data from DRIVE PK Study Demonstrating AG-348 is Well-Tolerated and Results in Clinically Relevant, Rapid and Sustained Hemoglobin Increases in Patients with Pyruvate Kinase Deficiency.

    Media Release 

////////////MITAPIVAT, PHASE 3, Orphan Drug Status, Inborn error metabolic disorders, AGIOS

ABACAVIR


Abacavir
Abacavir.svg
Abacavir
CAS Registry Number: 136470-78-5
CAS Name: (1S,4R)-4-[2-Amino-6-(cyclopropylamino)-9H-purin-9-yl]-2-cyclopentene-1-methanol
Additional Names: (-)-cis-4-[2-amino-6-(cyclopropylamino)-9H-purin-9-yl]-2-cyclopentene-1-methanol
Manufacturers’ Codes: 1592U89
Molecular Formula: C14H18N6O
Molecular Weight: 286.33
Percent Composition: C 58.73%, H 6.34%, N 29.35%, O 5.59%
Literature References: Nucleoside reverse transcriptase inhibitor (NRTI).
Prepn: S. M. Daluge, EP 349242 (1990 to Wellcome Found.); idem, US 5034394 (1991 to Burroughs Wellcome). Asymmetric synthesis: M. T. Crimmins, B. W. King, J. Org. Chem. 61,4192 (1996).
Pharmacology and biological profile: S. M. Daluge et al., Antimicrob. Agents Chemother. 41, 1082 (1997).
Review of antiviral activity and clinical evaluations: R. H. Foster, D. Faulds, Drugs 55, 729-736 (1998).
Clinical trial of triple nucleoside regimen in HIV patients: S. Staszewski et al., J. Am. Med. Assoc. 285, 1155 (2001).
Properties: White solid foam from acetonitrile, mp 165°. uv max (pH 1): 296, 255 nm (e 14000, 10700); uv max (pH 7): 284, 259 nm (e 15900, 9200); uv max (pH 13): 284, 259 nm (e 15800, 9100). [a]D20 -59.7°; [a]43620 -127.8°; [a]36520 -218.1° (c = 0.15 in methanol). Log P (1-octanol/0.1M sodium phosphate): 1.22 ±0.03 (pH 7.4). pKa 5.01. Soly in water (25°): >80 mM (pH 7).
Melting point: mp 165°
pKa: pKa 5.01
Optical Rotation: [a]D20 -59.7°; [a]43620 -127.8°; [a]36520 -218.1° (c = 0.15 in methanol)
Log P: Log P (1-octanol/0.1M sodium phosphate): 1.22 ±0.03 (pH 7.4)
Absorption maximum: uv max (pH 1): 296, 255 nm (e 14000, 10700); uv max (pH 7): 284, 259 nm (e 15900, 9200); uv max (pH 13): 284, 259 nm (e 15800, 9100)
Derivative Type: Sulfate
CAS Registry Number: 188062-50-2
Trademarks: Ziagen (GSK)
Molecular Formula: (C14H18N6O)2.H2SO4
Molecular Weight: 670.74
Percent Composition: C 50.14%, H 5.71%, N 25.06%, O 14.31%, S 4.78%
Therap-Cat: Antiviral.
Keywords: Reverse Transcriptase Inhibitor; Antiviral; Purines/Pyrimidinones.

Abacavir (ABC) is a medication used to prevent and treat HIV/AIDS.[1][2] Similar to other nucleoside analog reverse-transcriptase inhibitors (NRTIs), abacavir is used together with other HIV medications, and is not recommended by itself.[3] It is taken by mouth as a tablet or solution and may be used in children over the age of three months.[1][4]

Abacavir is generally well tolerated.[4] Common side effects include vomiting, trouble sleeping, fever, and feeling tired.[1] More severe side effects include hypersensitivityliver damage, and lactic acidosis.[1] Genetic testing can indicate whether a person is at higher risk of developing hypersensitivity.[1] Symptoms of hypersensitivity include rash, vomiting, and shortness of breath.[4] Abacavir is in the NRTI class of medications, which work by blocking reverse transcriptase, an enzyme needed for HIV virus replication.[5] Within the NRTI class, abacavir is a carbocyclic nucleoside.[1]

Abacavir was patented in 1988 and approved for use in the United States in 1998.[6][7] It is on the World Health Organization’s List of Essential Medicines, the most effective and safe medicines needed in a health system.[8] It is available as a generic medication.[1] The wholesale cost in the developing world as of 2014 is between US$0.36 and US$0.83 per day.[9] As of 2016 the wholesale cost for a typical month of medication in the United States is US$70.50.[10] Commonly, abacavir is sold together with other HIV medications, such as abacavir/lamivudine/zidovudineabacavir/dolutegravir/lamivudine, and abacavir/lamivudine.[4][5]

Medical uses

Two Abacavir 300mg tablets

Abacavir tablets and oral solution, in combination with other antiretroviral agents, are indicated for the treatment of HIV-1 infection.

Abacavir should always be used in combination with other antiretroviral agents. Abacavir should not be added as a single agent when antiretroviral regimens are changed due to loss of virologic response.

Side effects

Common adverse reactions include nausea, headache, fatigue, vomiting, diarrhea, loss of appetite and trouble sleeping. Rare but serious side effects include hypersensitivity reaction or rash, elevated AST and ALT, depression, anxiety, fever/chills, URI, lactic acidosis, hypertriglyceridemia, and lipodystrophy.[11]

People with liver disease should be cautious about using abacavir because it can aggravate the condition. Signs of liver problems include nausea and vomiting, abdominal pain, dark-colored urine and yellowing of the skin or whites of the eyes. The use of nucleosidedrugs such as abacavir can very rarely cause lactic acidosis. Signs of lactic acidosis include fast or irregular heartbeat, unusual muscle pain, fatigue, difficulty breathing and stomach pain with nausea and vomiting.[12] Abacavir can also lead to immune reconstitution inflammatory syndrome, a change in body fat as well as an increased risk of heart attack.

Resistance to abacavir has developed in laboratory versions of HIV which are also resistant to other HIV-specific antiretrovirals such as lamivudinedidanosine, and zalcitabine. HIV strains that are resistant to protease inhibitors are not likely to be resistant to abacavir.

Abacavir is contraindicated for use in infants under 3 months of age.

Little is known about the effects of Abacavir overdose. Overdose victims should be taken to a hospital emergency room for treatment.

Hypersensitivity syndrome

Hypersensitivity to abacavir is strongly associated with a specific allele at the human leukocyte antigen B locus namely HLA-B*5701.[13][14][15] There is an association between the prevalence of HLA-B*5701 and ancestry. The prevalence of the allele is estimated to be 3.4 to 5.8 percent on average in populations of European ancestry, 17.6 percent in Indian Americans, 3.0 percent in Hispanic Americans, and 1.2 percent in Chinese Americans.[16][17] There is significant variability in the prevalence of HLA-B*5701 among African populations. In African Americans, the prevalence is estimated to be 1.0 percent on average, 0 percent in the Yorubafrom Nigeria, 3.3 percent in the Luhya from Kenya, and 13.6 percent in the Masai from Kenya, although the average values are derived from highly variable frequencies within sample groups.[18]

Common symptoms of abacavir hypersensitivity syndrome include fevermalaisenausea, and diarrhea. Some patients may also develop a skin rash.[19] Symptoms of AHS typically manifest within six weeks of treatment using abacavir, although they may be confused with symptoms of HIVimmune reconstitution syndrome, hypersensitivity syndromes associated with other drugs, or infection.[20] The U.S. Food and Drug Administration (FDA) released an alert concerning abacavir and abacavir-containing medications on July 24, 2008,[21] and the FDA-approved drug label for abacavir recommends pre-therapy screening for the HLA-B*5701 allele and the use of alternative therapy in subjects with this allele.[22] Additionally, both the Clinical Pharmacogenetics Implementation Consortium and the Dutch Pharmacogenetics Working Group recommend use of an alternative therapy in individuals with the HLA-B*5701 allele.[23][24]

Skin-patch testing may also be used to determine whether an individual will experience a hypersensitivity reaction to abacavir, although some patients susceptible to developing AHS may not react to the patch test.[25]

The development of suspected hypersensitivity reactions to abacavir requires immediate and permanent discontinuation of abacavir therapy in all patients, including patients who do not possess the HLA-B*5701 allele. On March 1, 2011, the FDA informed the public about an ongoing safety review of abacavir and a possible increased risk of heart attack associated with the drug. A meta-analysis of 26 studies conducted by the FDA, however, did not find any association between abacavir use and heart attack [26][27]

Immunopathogenesis

The mechanism underlying abacavir hypersensitivity syndrome is related to the change in the HLA-B*5701 protein product. Abacavir binds with high specificity to the HLA-B*5701 protein, changing the shape and chemistry of the antigen-binding cleft. This results in a change in immunological tolerance and the subsequent activation of abacavir-specific cytotoxic T cells, which produce a systemic reaction known as abacavir hypersensitivity syndrome.[28]

Interaction

Abacavir, and in general NRTIs, do not undergo hepatic metabolism and therefore have very limited (to none) interaction with the CYP enzymes and drugs that effect these enzymes. That being said there are still few interactions that can affect the absorption or the availability of abacavir. Below are few of the common established drug and food interaction that can take place during abacavir co-administration:

  • Protease inhibitors such as tipranavir or ritonovir may decrease the serum concentration of abacavir through induction of glucuronidation. Abacavir is metabolized by both alcohol dehydrogenase and glucuronidation.[29][30]
  • Ethanol may result in increased levels of abacavir through the inhibition of alcohol dehydrogenase. Abacavir is metabolized by both alcohol dehydrogenase and glucuronidation.[29][31]
  • Methadone may diminish the therapeutic effect of Abacavir. Abacavir may decrease the serum concentration of Methadone.[32][33]
  • Orlistat may decrease the serum concentration of antiretroviral drugs. The mechanism of this interaction is not fully established but it is suspected that it is due to the decreased absorption of abacavir by orlistat.[34]
  • Cabozantinib: Drugs from the MPR2 inhibitor (Multidrug resistance-associated protein 2 inhibitors) family such as abacavir could increase the serum concentration of Cabozantinib.[35]

Mechanism of action

Abacavir is a nucleoside reverse transcriptase inhibitor that inhibits viral replication. It is a guanosine analogue that is phosphorylated to carbovir triphosphate (CBV-TP). CBV-TP competes with the viral molecules and is incorporated into the viral DNA. Once CBV-TP is integrated into the viral DNA, transcription and HIV reverse transcriptase is inhibited.[36]

Pharmacokinetics

Abacavir is given orally and is rapidly absorbed with a high bioavailability of 83%. Solution and tablet have comparable concentrations and bioavailability. Abacavir can be taken with or without food.

Abacavir can cross the blood-brain barrier. Abacavir is metabolized primarily through the enzymes alcohol dehydrogenase and glucuronyl transferase to an inactive carboxylate and glucuronide metabolites. It has a half-life of approximately 1.5-2.0 hours. If a person has liver failure, abacavir’s half life is increased by 58%.

Abacavir is eliminated via excretion in the urine (83%) and feces (16%). It is unclear whether abacavir can be removed by hemodialysis or peritoneal dialysis.[36]

History

Robert Vince and Susan Daluge along with Mei Hua, a visiting scientist from China, developed the medication in the ’80s.[37][38][39]

Abacavir was approved by the Food and Drug Administration (FDA) on December 18, 1998, and is thus the fifteenth approved antiretroviral drug in the United States. Its patent expired in the United States on 2009-12-26.

Synthesis

Abacavir synthesis:[40]

References

From internet free resources
From internet free resources
From internet free resources
From internet free resources

ABOVE From internet free resources

SYN
  1. Crimmins, M. T.; King, B. W. (1996). “An Efficient Asymmetric Approach to Carbocyclic Nucleosides: Asymmetric Synthesis of 1592U89, a Potent Inhibitor of HIV Reverse Transcriptase”. The Journal of Organic Chemistry61 (13): 4192–4193. doi:10.1021/jo960708pPMID 11667311.

Image result for abacavir synthesis
 
The reaction of 4,6-dihydroxypyrimidine-2,5-diamine (I) with (chloromethylene)dimethylammonium chloride (II) in refluxing chloroform gives 4,6-dichloro-2,5-bis(dimethylaminomethyleneamino)pyrimidine (III), which by reaction with aqueous HCl in hot ethanol yields monoamine (IV). The reaction of (IV) with a refluxing phosphate buffer (pH 3.2) affords N-(2-amino-4,6-dichloropyrimidin-5-yl)formamide (V). The condensation of (V) with (1S,4R)-4-amino-2-cyclopentene-1-methanol (VI) (which was obtained by optical resolution of the cis-racemate (VII) with D-dibenzoyltartaric acid, and elimination of the acid with ion exchange resin Amberlite IA-400, by means of triethylamine and NaOH in refluxing ethanol) gives N-[2-amino-4-chloro-6-[4(S)-(hydroxymethyl)-2-cyclopenten-1(R)-ylamino]pyrimidin-5-yl]formamide (VIII). The cyclization of (VIII) with refluxing diethoxymethyl acetate or triethyl orthoformate yields the corresponding purine derivative (IX), which is finally treated with cyclopropylamine (X) in refluxing n-butanol. 2) The formylation of N-(5-amino-4,6-dichloropyrimidin-2-yl)acetamide (XI) with 95% formic acid in acetic anhydride gives the expected formamide (XII), which is condensed with (1S,4R)-4-amino-2-cyclopentene-1-methanol (VI) by means of triethylamine in hot ethanol to yield the substituted pyrimidine (XIII). Finally, the cyclization of (XIII) with diethoxymethyl acetate as before affords the purine intermediate (IX).
AU 8937025; EP 0349242; JP 1990045486; JP 1999139976; US 5034394; US 5089500

 

SYN 2

The condensation of (?-cis-4-acetamido-2-cyclopentenylmethyl acetate (XIV) with 2-amino-4,6-dichloropyrimidine (XV) by means of Ba(OH)2 and triethylamine in refluxing butanol gives the expected condensation product (XVI), which is treated with 4-chlorophenyldiazonium chloride (XVII) in water/acetic acid to yield the corresponding azo-compound (XVIII). The reduction of (XVIII) with Zn/acetic acid in ethanol affords the diamine (XIX), which is cyclized with refluxing diethoxymethyl acetate (XX) to afford the corresponding purine (XXI). The reaction of (XXI) with cyclopropylamine (X) in refluxing ethanol affords racemic abacavir (XXII), which is phosphorylated with POCl3 giving the racemic 4′-O-phosphate (XXIII). Finally, this compound is submitted to stereoselective enzymatic dephosphorylation using snake venom 5′-nucleotidase (EC 3.1.3.5) from Crotalus atrox yielding the (-)-enantiomer, abacavir.

SYN 3

The acylation of 4(S)-benzyloxazolidin-2-one (XXIV) with 4-pentenoyl pivaloyl anhydride (XXV) by means of NaH in THF gives 4(S)-benzyl-3-(4-pentenoyl)oxazolidin-2-one (XXVI), which is submitted to a diastereoselective syn aldol condensation with acrolein (XXVII), using dibutylboron triflate as catalyst, affording the aldol (XXVIII). The cyclization of (XXVIII) by means of the Grubbs catalyst in dichloromethane yields the cyclopentenol (XXIX), which is reduced with LiBH4 in THF/methanol to give the key intermediate 5(R)-(hydroxymethyl)-2-cyclopenten-1(R)-ol (XXX). The reaction of (XXX) with methyl chloroformate/pyridine/DMAP or methyl chloroformate/triethylamine/DMAP or acetic anhydride gives the diols (XXXI), (XXXII) and (XXXIII), respectively, each of which coupled with 2-amino-6-chloropurine (XXXIV) in the presence of NaH and palladium tetrakis(triphenylphosphine) in THF/DMSO, affords the purine intermediate (IX) already reported.

SYN

The water promoted condensation of glyoxylic acid (XXXV) with cyclopentadiene (XXXVI) gives the racemic cis-hydroxylactone (XXXVII), which is acetylated with acetic anhydride to the acetate (XXXVIII). The selective enzymatic hydrolysis of (XXXVIII) with Pseudomonas fluorescens lipase yields the pre (-)-enantiomer (XXXIX), which is reduced with LiAlH4 in refluxing THF, affording triol (XL). The oxidation of the vicinal glycol of (XL) with NaIO4 in ethyl ether/water yields the hydroxyaldehyde (XLI), which is reduced with NaBH4 in ethanol to give the key intermediate 5(R)-(hydroxymethyl)-2-cyclopenten-1(R)-ol (XXX). This compound, by reaction with triphosgene and triethylamine in dichloromethane, results in the cyclic carbonate intermediate (XXXII), already reported.

SYN

A new solid phase synthesis of abacavir has been reported: Condensation of the chiral 4(R)-benzyl-3-(4-pentenoyl)oxazolidin-2-thione (I) with acrolein (II) by means of TiCl4 and DIEA gives the adduct (III), which was transformed into the chiral cyclopentene (IV) by catalytic ring-closing metathesis. The reductive removal of the chiral auxiliary with LiBH4 affords the chiral diol (V), which is selectively silylated with TBDMSCl providing the primary silyl ether (VI). Acylation of the secondary alcohol of (VI) with benzoic anhydride gives the benzoate (VII), which is desilylated with HF in acetonitrile yielding the allylic benzoate (VIII). Benzoate (VIII) is condensed with a p-nitrophenyl Wang carbonate resin (IX) by means of DIEA and DMAP affording the solid phase resin (X) which is condensed with 2-amino-6-chloropurine (XI) by means of a Pd catalyst furnishing the adduct (XII). Thermal condensation of (XII) with cyclopropylamine (XIII) yields the diaminopurine resin (XIV) which, after cleavage from the resin by a treatment with TFA in dichloromethane, gives directly abacavir.

SYN

The condensation of the chiral oxazolidinone (I) with the pentenoic anhydride (II) by means of n-BuLi in THF gives the N-pentenoyloxazolidinone (III), which is condensed with acrolein (IV) catalyzed by TiCl4 and (-)-spartein in dichloromethane, yielding the chiral adduct (V). The ring-closing metathesis of (V) by means of a Ru catalyst in dichloromethane affords the chiral cyclopentenol derivative (VI), which is reduced to the (R,R)-5-(hydroxymethyl)-2-cyclopenten-1-ol (VII) by means of LiBH4 in THF. The reaction of diol (VII) with Ac2O; with methyl chloroformate, TEA and DMAP; or with ethyl chloroformate and pyridine gives the diacetate (VIII), the cyclic carbonate (IX) or the dicarbonate (X), respectively. The condensation of (VIII), (IX) or (X) with 2-amino-6-chloropurine (XI) by means of Pd(PPh3)4 yields the carbocyclic purines (XII), (XIII) or (XIV), respectively. Finally, these compounds are hydrolyzed with aqueous NaOH to the target carbocyclic guanine.

SYN

Alternatively, the (R,R)-5-(hydroxymethyl)-2-cyclopenten-1-ol (VII) can also be obtained as follows: The condensation of the chiral oxazolidinethione (XV) with the pentenoic anhydride (II) by means of n-BuLi in THF gives the N-pentenoyloxazolidinethione (XVI), which is condensed with crotonaldehyde (XVII) catalyzed by TiCl4 and (-)-spartein in dichloromethane, yielding the chiral adduct (XVIII). The ring-closing metathesis of (XVIII) by means of a Ru catalyst in dichloromethane affords the chiral cyclopentenol derivative (XIX), which is reduced to the target diol (VII) by means of LiBH4 in THF.

SYN

An efficient asymmetric synthesis of abacavir has been reported: Acylation of the chiral oxazolidinone (I) with the mixed anhydride (II) by means of BuLi in THF gives the N-pentenoyloxazolidinone (III), which by condensation with acrolein (IV) catalyzed by TiCl4 and (?-spartein in dichloromethane yields the chiral adduct (V). The ring-closing metathesis of adduct (V) by means of the ruthenium catalyst (Cy3P)Cl2Ru=CHPh in dichloromethane affords the chiral cyclopentenol (VI), which is reduced to 5(R)-(hydroxymethyl)-2-cyclopenten-1(R)-ol (VII) by means of LiBH4 in THF. Reaction of diol (VII) with a) Ac2O, TEA and DMAP, b) methyl chloroformate, TEA and DMAP or c) methyl chloroformate, pyridine and DMAP gives a) the diacetate (VIII), b) the cyclic carbonate (IX) or c) the dicarbonate (X), respectively. The condensation of diacetate (VIII), cyclic carbonate (IX) or dicarbonate (X) with 2-amino-6-chloropurine (XI) by means of Pd(PPh3)4 yields the carbocyclic purines (XII), (XIII) or (XIV), respectively. Treatment of these chloro-purines (XII), (XIII) and (XIV) with cyclopropylamine (XV) in hot DMSO provides the corresponding cyclopropylaminopurine carbonate (XVI), abacavir or cyclopropylaminopurine acetate (XVII), respectively. Finally, the protecting groups of purines (XVI) and (XVII) are hydrolyzed with aqueous NaOH.

SYN

Alternatively, 5(R)-(hydroxymethyl)-2-cyclopenten-1(R)-ol (VII) can also be obtained as follows: Acylation of the chiral oxazolidinethione (XIX) with the mixed anhydride (II) by means of BuLi in THF gives the N-pentenoyl-oxazolidinethione (XX), which by condensation with crotonaldehyde (XXI) catalyzed by TiCl4 and (?-spartein in dichloromethane yields the chiral adduct (XXII). The ring-closing metathesis of (XXII) by means of the ruthenium catalyst in dichloromethane affords the chiral cyclopentenol derivative (XXIII), which is reduced to the target diol (VII) by means of LiBH4 in THF.

SYN

Alternatively, 2-amino-6-chloropurine (XI) is treated with cyclopropylamine (XV) in hot DMSO to give 2-amino-6-(cyclopropylamino)purine (XVIII), which is condensed with the chiral diacetate (VIII) by means of Pd(PPh3)4 to yield the carbocyclic purine acetate (XVI). Finally, purine (XVI) is deprotected by hydrolysis with aqueous NaOH.

CLIP

Image result for abacavir synthesis

https://www.sciencedirect.com/science/article/pii/S0960894X15007581

CLIP

Image result for abacavir synthesis

CLIP

CLIP

 Production of Abacavir
030-8 1.0g (0.0053mol), in the reaction flask was added cesium carbonate 1.75 g (0.0054 mol) and dry DMSO 50ml, stirred under N2 protection, the temperature was raised to 60 °C and stirred at this temperature for 2 h the mixture wascooled to room temperature, then add tetrakis (triphenylphosphine) combined palladium (TTP) [0.85 (0.00074mol)] and compound 030-5 [0.79g (0.0034 mol), DMSO (10 ml) solution was stirred and heated to 65 °C held 65 °C and stirred reaction 2.25h. The you can get the mixture containing compounds 030-9.

To the mixture was added methanol 100ml and K2CO3 is 2.10g, the mixture reaction was stirred for 45min at 40 °C, a solid precipitate which was filtered through a Celite layer and the filtrate was evaporated to a small volume under vacuum at 90 °C, and the remaining gum pounding mill was extracted with dichloromethane (100ml * 2) to give a brown solid residue was purified by silica gel (Merck 9385) column chromatography [eluent: dichloromethane / methanol (volume ratio 9:1)] to give a yellow foam was 030 0.26 g, yield 26.8.

Production of Abacavir

CLIP

Image result for abacavir synthesis

https://pubs.rsc.org/en/content/articlehtml/2012/ra/c2ra20842c

References

  1. Jump up to:a b c d e f g h “Abacavir Sulfate”. The American Society of Health-System Pharmacists. Archived from the original on 8 September 2017. Retrieved 31 July 2015.
  2. ^ “Drug Name Abbreviations Adult and Adolescent ARV Guidelines”AIDSinfoArchived from the original on 2016-11-09. Retrieved 2016-11-08.
  3. ^ “What Not to Use Adult and Adolescent ARV Guidelines”AIDSinfoArchived from the original on 2016-11-09. Retrieved 2016-11-08.
  4. Jump up to:a b c d Yuen, GJ; Weller, S; Pakes, GE (2008). “A review of the pharmacokinetics of abacavir”. Clinical Pharmacokinetics47 (6): 351–71. doi:10.2165/00003088-200847060-00001PMID 18479171.
  5. Jump up to:a b “Nucleoside reverse transcriptase inhibitors (NRTIs or ‘nukes’) – HIV/AIDS”http://www.hiv.va.govArchived from the original on 2016-11-09. Retrieved 2016-11-08.
  6. ^ Fischer, Janos; Ganellin, C. Robin (2006). Analogue-based Drug Discovery. John Wiley & Sons. p. 505. ISBN 9783527607495Archived from the original on 2017-09-08.
  7. ^ Kane, Brigid M. (2008). HIV/AIDS Treatment Drugs. Infobase Publishing. p. 56. ISBN 9781438102078Archived from the original on 2017-09-08.
  8. ^ “WHO Model List of Essential Medicines (19th List)” (PDF)World Health Organization. April 2015. Archived (PDF) from the original on 13 December 2016. Retrieved 8 December 2016.
  9. ^ “International Drug Price Indicator Guide”ERC. Retrieved 20 November 2016.
  10. ^ “NADAC as of 2016-12-07 | Data.Medicaid.gov”Centers for Medicare and Medicaid ServicesArchived from the original on 21 December 2016. Retrieved 12 December 2016.
  11. ^ “Abacavir Adverse Reactions”Epocrates Online.
  12. ^ “Abacavir | Dosage, Side Effects | AIDSinfo”AIDSinfoArchived from the original on 2017-03-06. Retrieved 2016-11-08.
  13. ^ Mallal, S., Phillips, E., Carosi, G.; et al. (2008). “HLA-B*5701 screening for hypersensitivity to abacavir”. New England Journal of Medicine358 (6): 568–579. doi:10.1056/nejmoa0706135PMID 18256392.
  14. ^ Rauch, A., Nolan, D., Martin, A.; et al. (2006). “Prospective genetic screening decreases the incidence of abacavir hypersensitivity reactions in the Western Australian HIV cohort study”. Clinical Infectious Diseases43 (1): 99–102. doi:10.1086/504874PMID 16758424.
  15. ^ Dean, Laura (2012), Pratt, Victoria; McLeod, Howard; Rubinstein, Wendy; Dean, Laura (eds.), “Abacavir Therapy and HLA-B*57:01 Genotype”Medical Genetics Summaries, National Center for Biotechnology Information (US), PMID 28520363, retrieved 2019-01-14
  16. ^ Heatherington; et al. (2002). “Genetic variations in HLA-B region and hypersensitivity reactions to abacavir”. Lancet359 (9312): 1121–1122. doi:10.1016/s0140-6736(02)08158-8PMID 11943262.
  17. ^ Mallal; et al. (2002). “Association between presence of HLA*B5701, HLA-DR7, and HLA-DQ3 and hypersensitivity to HIV-1 reverse-transcriptase inhibitor abacavir”. Lancet359(9308): 727–732. doi:10.1016/s0140-6736(02)07873-xPMID 11888582.
  18. ^ Rotimi, C. N.; Jorde, L. B. (2010). “Ancestry and disease in the age of genomic medicine”. New England Journal of Medicine363 (16): 1551–1558. doi:10.1056/nejmra0911564PMID 20942671.
  19. ^ Phillips, E., Mallal, S. (2009). “Successful translation of pharmacogenetics into the clinic”. Molecular Diagnosis & Therapy13: 1–9. doi:10.1007/bf03256308.
  20. ^ Phillips, E., Mallal S. (2007). “Drug hypersensitivity in HIV”. Current Opinion in Allergy and Clinical Immunology7 (4): 324–330. doi:10.1097/aci.0b013e32825ea68aPMID 17620824.
  21. ^ “Postmarket Drug Safety Information for Patients and Providers – Information for Healthcare Professionals: Abacavir (marketed as Ziagen) and Abacavir-Containing Medications”Center for Drug Evaluation and Research at the US FDAArchived from the original on 2013-12-11. Retrieved 2013-11-29.
  22. ^ “Archived copy”Archived from the original on 2014-08-08. Retrieved 2014-07-31.
  23. ^ Swen JJ, Nijenhuis M, de Boer A, et al. (May 2011). “Pharmacogenetics: from bench to byte–an update of guidelines”. Clin Pharmacol Ther89 (5): 662–73. doi:10.1038/clpt.2011.34PMID 21412232.
  24. ^ Martin MA, Hoffman JM, Freimuth RR, et al. (May 2014). “Clinical Pharmacogenetics Implementation Consortium Guidelines for HLA-B Genotype and Abacavir Dosing: 2014 update”Clin Pharmacol Ther95 (5): 499–500. doi:10.1038/clpt.2014.38PMC 3994233PMID 24561393.
  25. ^ Shear, N.H., Milpied, B., Bruynzeel, D. P.; et al. (2008). “A review of drug patch testing and implications for HIV clinicians”. AIDS22 (9): 999–1007. doi:10.1097/qad.0b013e3282f7cb60PMID 18520343.
  26. ^ “FDA Alert: Abacavir – Ongoing Safety Review: Possible Increased Risk of Heart Attack”Drugs.comArchived from the original on 2013-12-10. Retrieved 2013-11-29.
  27. ^ Ding X, Andraca-Carrera E, Cooper C, et al. (December 2012). “No association of abacavir use with myocardial infarction: findings of an FDA meta-analysis”. J Acquir Immune Defic Syndr61 (4): 441–7. doi:10.1097/QAI.0b013e31826f993cPMID 22932321.
  28. ^ Illing, PT; et al. (2012). “Immune self-reactivity triggered by drug-modified HLA-peptide repertoire”. Nature486 (7404): 554–8. doi:10.1038/nature11147PMID 22722860.
  29. Jump up to:a b Prescribing information. Ziagen (abacavir). Research Triangle Park, NC: GlaxoSmithKline, July 2002
  30. ^ Vourvahis, M; Kashuba, AD (2007). “Mechanisms of Pharmacokinetic and Pharmacodynamic Drug Interactions Associated with Ritonavir-Enhanced Tipranavir”. Pharmacotherapy27 (6): 888–909. doi:10.1592/phco.27.6.888PMID 17542771.
  31. ^ McDowell, JA; Chittick, GE; Stevens, CP; et al. (2000). , “Pharmacokinetic Interaction of Abacavir (1592U89) and Ethanol in Human Immunodeficiency Virus-Infected Adults”Antimicrob Agents Chemother44 (6): 1686–90. doi:10.1128/aac.44.6.1686-1690.2000PMC 89933PMID 10817729.
  32. ^ Berenguer, J; Perez-Elias, MJ; Bellon, JM; et al. (2006). “Effectiveness and safety of abacavir, lamivudine, and zidovudine in antiretroviral therapy-naive HIV-infected patients: results from a large multicenter observational cohort”. J Acquir Immune Defic Syndr41 (2): 154–159. doi:10.1097/01.qai.0000194231.08207.8aPMID 16394846.
  33. ^ Dolophine(methadone) [prescribing information]. Columbus, OH: Roxane Laboratories, Inc.; March 2015.
  34. ^ Gervasoni, C; Cattaneo, D; Di Cristo, V; et al. (2016). “Orlistat: weight lost at cost of HIV rebound”. J Antimicrob Chemother71 (6): 1739–1741. doi:10.1093/jac/dkw033PMID 26945709.
  35. ^ Cometriq (cabozantinib) [prescribing information]. South San Francisco, CA: Exelixis, Inc.; May 2016.
  36. Jump up to:a b Product Information: ZIAGEN(R) oral tablets, oral solution, abacavir sulfate oral tablets, oral solution. ViiV Healthcare (per Manufacturer), Research Triangle Park, NC, 2015.
  37. ^ “Dr. Robert Vince – 2010 Inductee”Minnesota Inventors Hall of Fame. Minnesota Inventors Hall of Fame. Archived from the original on 15 February 2016. Retrieved 10 February 2016.
  38. ^ “Robert Vince, PhD (faculty listing)”University of Minnesota. University of Minnesota. Archived from the original on 2016-02-17.
  39. ^ Daluge SM, Good SS, Faletto MB, Miller WH, St Clair MH, Boone LR, Tisdale M, Parry NR, Reardon JE, Dornsife RE, Averett DR (May 1997). “1592U89, a novel carbocyclic nucleoside analog with potent, selective anti-human immunodeficiency virus activity”Antimicrobial Agents and Chemotherapy41 (5): 1082–1093. doi:10.1128/AAC.41.5.1082PMC 163855PMID 9145874.
  40. ^ Crimmins, M. T.; King, B. W. (1996). “An Efficient Asymmetric Approach to Carbocyclic Nucleosides: Asymmetric Synthesis of 1592U89, a Potent Inhibitor of HIV Reverse Transcriptase”. The Journal of Organic Chemistry61 (13): 4192–4193. doi:10.1021/jo960708pPMID 11667311.

External links

References

    •  Crimmins, M.T. et al.: J. Org. Chem. (JOCEAH) 61 4192 (1996).
    • b Olivo, H.F. et al.: J. Chem. Soc., Perkin Trans. 1 (JCPRB4) 1998, 391.
    • US 5 089 500 (Burroughs Wellcome; 18.2.1992; GB-prior. 27.6.1988).
    • a EP 434 450 (Wellcome Found.; 26.6.1991; appl. 21.12.1990; USA-prior. 22.12.1989).
    •  EP 1 857 458 (Solmag; appl. 5.5.2006).
    • aa EP 424 064 (Enzymatix; appl. 24.4.1991; GB-prior. 16.10.1989).
    •  US 6 340 587 (SmithKline Beecham; 22.1.2002; appl. 20.8.1998; GB-prior. 22.8.1997).
    • c US 5 034 394 (Welcome Found.; 23.7.1991; appl. 22.12.1989; GB-prior. 27.6.1988).
    • d WO 9 924 431 (Glaxo; appl. 12.11.1998; WO-prior. 12.11.1997).
  • Alternative syntheses:

    • EP 878 548 (Lonza; appl. 13.5.1998; CH-prior. 13.5.1997).
  • Preparation of chloropyrimidine intermediate V:

    • US 6 448 403 (SmithKline Beecham; 10.9.2002; appl. 3.2.1995; GB-prior. 4.2.1994).
  • Condensation of pyrimidines with cyclopentylamine IV:

    • Vince, R.; Hua, M.: J. Med. Chem. (JMCMAR) 33 (1), 17 (1990).
    • Grumam, A. et al.: Tetrahedron Lett. (TELEAY) 36 (42), 7767 (1995).
    • EP 349 242 (Wellcome Found.; appl. 26.6.1989; GB-prior. 27.6.1988).
    • EP 366 385 (Wellcome Found.; appl. 23.10.1989; GB-prior. 24.10.1988).
    • US 6 646 125 (SmithKline Beecham; 11.11.2003; appl. 14.10.1998; GB-prior. 14.10.1997).
    • JP 1 022 853 (Asahi Glass Co.; appl. 17.7.1987).
  • Alternative preparation of 4-amino-2-cyclopentene-1-methanol:

    • EP 926 131 (Lonza; appl. 24.11.1998; CH-prior. 27.11.1997).
    • WO 9 745 529 (Lonza; appl. 30.5.1997; CH-prior. 30.5.1996).
    • WO 9 910 519 (Glaxo; 4.3.1999; GB-prior. 20.8.1998).
    • WO 9 824 741 (Glaxo; 11.6.1998; GB-prior. 7.12.1996).
    • WO 2 001 017 952 (Chirotech; 15.3.2001; GB-prior. 9.9.1999).
  • Abacavir hemisulfate salt:

    • US 6 294 540 (Glaxo Wellcome; 25.9.2001; appl. 14.5.1998; GB-prior. 17.5.1997).
  • Abacavir succinate as antiviral agent:

    • WO 9 606 844 (Wellcome; 7.3.1996; appl. 25.8.1995; GB-prior. 26.8.1994).
  • Pharmaceutical formulations:

    • US 6 641 843 (SmithKline Beecham; 4.11.2003; appl. 4.2.1999; GB-prior. 6.2.1998).
  • Synergistic combinations for treatment of HIV infection:

    • WO 9 630 025 (Wellcome; 3.10.1996; appl. 28.3.1996; GB-prior. 30.3.1995).
Abacavir
Abacavir.svg
Abacavir ball-and-stick model.png

Chemical structure of abacavir
Clinical data
Pronunciation /əˈbækəvɪər/ (About this soundlisten)
Trade names Ziagen, others[1]
AHFS/Drugs.com Monograph
MedlinePlus a699012
License data
Pregnancy
category
  • AU: B3
  • US: C (Risk not ruled out)
Routes of
administration
By mouth (solution or tablets)
ATC code
Legal status
Legal status
Pharmacokinetic data
Bioavailability 83%
Metabolism Liver
Elimination half-life 1.54 ± 0.63 h
Excretion Kidney (1.2% abacavir, 30% 5′-carboxylic acid metabolite, 36% 5′-glucuronide metabolite, 15% unidentified minor metabolites). Fecal (16%)
Identifiers
CAS Number
PubChem CID
DrugBank
ChemSpider
UNII
KEGG
ChEBI
ChEMBL
NIAID ChemDB
ECHA InfoCard 100.149.341 Edit this at Wikidata
Chemical and physical data
Formula C14H18N6O
Molar mass 286.332 g/mol g·mol−1
3D model (JSmol)
Melting point 165 °C (329 °F)
/////////
OLD POST
Abacavir.svg
Abacavir 3d structure.png

Chemical structure of abacavir

{(1S,4R)-4-[2-amino-6-(cyclopropylamino)-9H-purin-9-yl]cyclopent-2-en-1-yl}methanol

(-)-cis-4-[2-Amino-6-(cyclopropylmethylamino)-9H-purin-9-yl]-2-cyclopentene-1-methanol

(1S, 4R)-4-[2-amino-6-(cyclopropylamino)-9H purin-9-yl]-2- cyclopentene-1 -methanol

136470-78-5

Abacavir

Abacavir (ABC) is a powerful nucleoside analog reverse transcriptase inhibitor (NRTI) used to treat HIV and AIDS. [Wikipedia] Chemically, it is a synthetic carbocyclic nucleoside and is the enantiomer with 1S, 4R absolute configuration on the cyclopentene ring. In vivo, abacavir sulfate dissociates to its free base, abacavir.

Abacavir (ABC) Listeni/ʌ.bæk.ʌ.vɪər/ is a nucleoside analog reverse transcriptase inhibitor (NRTI) used to treat HIV and AIDS. It is available under the trade name Ziagen (ViiV Healthcare) and in the combination formulations Trizivir (abacavir, zidovudine andlamivudine) and Kivexa/Epzicom (abacavir and lamivudine). It has been well tolerated: the main side effect is hypersensitivity, which can be severe, and in rare cases, fatal. Genetic testing can indicate whether an individual will be hypersensitive; over 90% of patients can safely take abacavir. However, in a separate study, the risk of heart attack increased by nearly 90%.[1]

Viral strains that are resistant to zidovudine (AZT) or lamivudine (3TC) are generally sensitive to abacavir (ABC), whereas some strains that are resistant to AZT and 3TC are not as sensitive to abacavir.

It is on the World Health Organization’s List of Essential Medicines, a list of the most important medication needed in a basic health system.[2]

Abacavir is a nucleoside reverse transcriptase inhibitor (NRTI) with activity against Human Immunodeficiency Virus Type 1 (HIV-1). Abacavir is phosphorylated to active metabolites that compete for incorporation into viral DNA. They inhibit the HIV reverse transcriptase enzyme competitively and act as a chain terminator of DNA synthesis. The concentration of drug necessary to effect viral replication by 50 percent (EC50) ranged from 3.7 to 5.8 μM (1 μM = 0.28 mcg/mL) and 0.07 to 1.0 μM against HIV-1IIIB and HIV-1BaL, respectively, and was 0.26 ± 0.18 μM against 8 clinical isolates. Abacavir had synergistic activity in cell culture in combination with the nucleoside reverse transcriptase inhibitor (NRTI) zidovudine, the non-nucleoside reverse transcriptase inhibitor (NNRTI) nevirapine, and the protease inhibitor (PI) amprenavir; and additive activity in combination with the NRTIs didanosine, emtricitabine, lamivudine, stavudine, tenofovir, and zalcitabine.

Brief background information

Salt ATC Formula MM CAS
J05AF06 C 14 H 18 N 6 O 286.34 g / mol 136470-78-5
succinate J05AF06 C 14 H 18 N 6 O · C 4 H 6 O 356.43 g / mol 168146-84-7
sulfate J05AF06 C 14 H 18 N 6 O · 1 / 2H 2 SO 4 670.76 g / mol 188062-50-2
Systematic (IUPAC) name
{(1S,4R)-4-[2-amino-6-(cyclopropylamino)-9H-purin-9-yl]cyclopent-2-en-1-yl}methanol
Clinical data
Trade names Ziagen
AHFS/Drugs.com monograph
MedlinePlus a699012
Pregnancy cat. B3 (AU) C (US)
Legal status POM (UK) -only (US)
Routes Oral (solution or tablets)
Pharmacokinetic data
Bioavailability 83%
Metabolism Hepatic
Half-life 1.54 ± 0.63 h
Excretion Renal (1.2% abacavir, 30% 5′-carboxylic acid metabolite, 36% 5′-glucuronide metabolite, 15% unidentified minor metabolites). Fecal (16%)
Identifiers
CAS number 136470-78-5 Yes
ATC code J05AF06
PubChem CID 441300
DrugBank DB01048
ChemSpider 390063 Yes
UNII WR2TIP26VS Yes
KEGG D07057 Yes
ChEBI CHEBI:421707 Yes
ChEMBL CHEMBL1380 Yes
NIAID ChemDB 028596
Chemical data
Formula C14H18N6O 
Mol. mass 286.332 g/mol

 Abacavir is a carbocyclic synthetic nucleoside analogue and an antiviral agent. Intracellularly, abacavir is converted by cellular enzymes to the active metabolite carbovir triphosphate, an analogue of deoxyguanosine-5′-triphosphate (dGTP). Carbovir triphosphate inhibits the activity of HIV-1 reverse transcriptase (RT) both by competing with the natural substrate dGTP and by its incorporation into viral DNA. Viral DNA growth is terminated because the incorporated nucleotide lacks a 3′-OH group, which is needed to form the 5′ to 3′ phosphodiester linkage essential for DNA chain elongation.

Application

  • an antiviral agent, is used in the treatment of AIDS
  • ingibitor convertibility transkriptazы

Classes of substances

  • Adenine (6-aminopurines)
    • Aminoalcohols
      • Cyclopentenes and cyclopentadienes
        • Tsyklopropanы

PATENT

US5034394

Synthesis pathway

Abacavir, (-) cis-[4-[2-amino-6-cyclopropylamino)-9H-purin-9-yl]-2-cyclopenten-yl]-1 – methanol, a carbocyclic nucleoside which possesses a 2,3-dehydrocyclopentene ring, is referred to in United States Patent 5,034,394 as a reverse transcriptase inhibitor. Recently, a general synthetic strategy for the preparation of this type of compound and intermediates was reported [Crimmins, et. al., J. Org. Chem., 61 , 4192-4193 (1996) and 65, 8499-8509-4193 (2000)].

    • Abacavir is the International Nonproprietary Name (INN) of {(1S,4R)-4-[2-amino-6-(cyclopropylamino)-9H-purin-9-yl]-cyclopent-2-enyl}methanol and CAS No. 136470-78-5. Abacavir and therapeutically acceptable salts thereof, in particular the hemisulfate salt, are well-known as potent selective inhibitors of HIV-1 and HIV-2, and can be used in the treatment of human immunodeficiency virus (HIV) infection.

The structure of abacavir corresponds to formula (I):

  • Figure imgb0001
  • EP 434450-A discloses certain 9-substituted-2-aminopurines including abacavir and its salts, methods for their preparation, and pharmaceutical compositions using these compounds.
  • Different preparation processes of abacavir are known in the art. In some of them abacavir is obtained starting from an appropriate pyrimidine compound, coupling it with a sugar analogue residue, followed by a cyclisation to form the imidazole ring and a final introduction of the cyclopropylamino group at the 6 position of the purine ring.
  • According to the teachings of EP 434450-A , the abacavir base is finally isolated by trituration using acetonitrile (ACN) or by chromatography, and subsequently it can be transformed to a salt of abacavir by reaction with the corresponding acid. Such isolation methods (trituration and chromatography) usually are limited to laboratory scale because they are not appropriate for industrial use. Furthermore, the isolation of the abacavir base by trituration using acetonitrile gives a gummy solid (Example 7) and the isolation by chromatography (eluted from methanol/ethyl acetate) yields a solid foam (Example 19 or 28).
  • Other documents also describe the isolation of abacavir by trituration or chromatography, but always a gummy solid or solid foam is obtained (cf. WO9921861 and EP741710 ), which would be difficult to operate on industrial scale.
  • WO9852949 describes the preparation of abacavir which is isolated from acetone. According to this document the manufacture of the abacavir free base produces an amorphous solid which traps solvents and is, therefore, unsuitable for large scale purification, or for formulation, without additional purification procedures (cf. page 1 of WO 9852949 ). In this document, it is proposed the use of a salt of abacavir, in particular the hemisulfate salt which shows improved physical properties regarding the abacavir base known in the art. Said properties allow the manufacture of the salt on industrial scale, and in particular its use for the preparation of pharmaceutical formulations.
  • However, the preparation of a salt of abacavir involves an extra processing step of preparing the salt, increasing the cost and the time to manufacture the compound. Generally, the abacavir free base is the precursor compound for the preparation of the salt. Thus, depending on the preparation process used for the preparation of the salt, the isolation step of the abacavir free base must also be done.

 

………………………………

http://www.google.co.in/patents/US5034394

EXAMPLE 21(-)-cis-4-[2-Amino-6-(cyclopropylmethylamino)-9H-purin-9-yl]-2-cyclopentene-1-methanol

The title compound of Example 7, (2.00 g, 6.50 mmol) was dissolved in 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)-pyrimidinone (Aldrich, 20 mL). Phosphoryl chloride (2.28 mL, 24.0 mmol) was added to the stirred, cooled (-10° C.) solution. After 3 minutes, cold water (80 mL) was added. The solution was extracted with chloroform (3×80 mL). The aqueous layer was diluted with ethanol (400 mL) and the pH adjusted to 6 with saturated aqueous NaOH. The precipitated inorganic salts were filtered off. The filtrate was further diluted with ethanol to a volume of 1 liter and the pH adjusted to 8 with additional NaOH. The resulting precipitate was filtered and dried to give the 5′-monophosphate of (±)-cis-4-[2-amino-6-(cyclopropylmethylamino)-9H-purin-9-yl]-2-cyclopentene-1-methanol as white powder (4.0 mmoles, 62% quantitated by UV absorbance); HPLC analysis as in Example 17 shows one peak. This racemic 5′ -monophosphate was dissolved in water (200 mL) and snake venom 5′-nucleotidase (EC 3.1.3.5) from Crotalus atrox (5,000 IU, Sigma) was added. After incubation at 37° C. for 10 days, HPLC analysis as in Example 17 showed that 50% of the starting nucleotide had been dephosphorylated to the nucleoside. These were separated on a 5×14 cm column of DEAE Sephadex A25 (Pharmacia) which had been preequilibrated with 50 mM ammonium bicarbonate. Title compound was eluted with 2 liters of 50 mM ammonium bicarbonate. Evaporation of water gave white powder which was dissolved in methanol, adsorbed on silica gel, and applied to a silica gel column. Title compound was eluted with methanol:chloroform/1:9 as a colorless glass. An acetonitrile solution was evaporated to give white solid foam, dried at 0.3 mm Hg over P2 O5 ; 649 mg (72% from racemate); 1 H-NMR in DMSO-d6 and mass spectrum identical with those of the racemate (title compound of Example 7); [α]20 D -48.0°, [α]20 436 -97.1°, [α]20 365 -149° (c=0.14, methanol).

Anal. Calcd. for C15 H20 N6 O.0.10CH3 CN: C, 59.96; H, 6.72; N, 28.06. Found: C, 59.93; H, 6.76; N, 28.03.

Continued elution of the Sephadex column with 2 liters of 100 mM ammonium bicarbonate and then with 2 liters of 200 mM ammonium bicarbonate gave 5′-monophosphate (see Example 22) which was stable to 5′-nucleotidase.

…………………………………………

Синтез a)







Синтез b)




Preparation c)



Synthesis d)

An enantiopure β-lactam with a suitably disposed electron withdrawing group on nitrogen, participated in a π-allylpalladium mediated reaction with 2,6-dichloropurine tetrabutylammonium salt to afford an advanced cis-1,4-substituted cyclopentenoid with both high regio- and stereoselectivity. This advanced intermediate was successfully manipulated to the total synthesis of (−)-Abacavir.

Graphical abstract: Enantioselective synthesis of the carbocyclic nucleoside (−)-abacavir

http://pubs.rsc.org/en/content/articlelanding/2012/ob/c2ob06775g#!divAbstract

………………………………….

http://www.google.com.ar/patents/EP2085397A1?cl=en

Example 1: Preparation of crystalline Form I of abacavir base using methanol as solvent

  • [0026]
    Abacavir (1.00 g, containing about 17% of dichloromethane) was dissolved in refluxing methanol (2.2 mL). The solution was slowly cooled to – 5 °C and, the resulting suspension, was kept at that temperature overnight under gentle stirring. The mixture was filtered off and dried under vacuum (7-10 mbar) at 40 °C for 4 hours to give a white solid (0.55 g, 66% yield, < 5000 ppm of methanol). The PXRD analysis gave the diffractogram shown in FIG. 1.

……………………………………..

http://www.google.com/patents/WO2008037760A1?cl=en

Abacavir, is the International Nonproprietary Name (INN) of {(1 S,4R)-4-[2- amino-6-(cyclopropylamino)-9H-purin-9-yl]-cyclopent-2-enyl}methanol, and CAS No. 136470-78-5. Abacavir sulfate is a potent selective inhibitor of HIV-1 and HIV-2, and can be used in the treatment of human immunodeficiency virus (HIV) infection.

The structure of abacavir hemisulfate salt corresponds to formula (I):

Figure imgf000002_0001

(I)

EP 434450-A discloses certain 9-substituted-2-aminopuhnes including abacavir and its salts, methods for their preparation, and pharmaceutical compositions using these compounds.

Different preparation processes of abacavir are known in the art. In some of them abacavir is obtained starting from an appropriate pyrimidine compound, coupling it with a sugar analogue residue, followed by a cyclisation to form the imidazole ring and a final introduction of the cyclopropylamino group at the 6 position of the purine ring. Pyrimidine compounds which have been identified as being useful as intermediates of said preparation processes include N-2-acylated abacavir intermediates such as N-{6- (cyclopropylamino)-9-[(1 R,4S)-4-(hydroxymethyl)cyclopent-2-enyl]-9H-purin- 2-yl}acetamide or N-{6-(cyclopropylamino)-9-[(1 R,4S)-4-

(hydroxymethyl)cyclopent-2-enyl]-9H-purin-2-yl}isobutyramide. The removal of the amino protective group of these compounds using acidic conditions is known in the art. According to Example 28 of EP 434450-A, the amino protective group of the N-{6-(cyclopropylamino)-9-[(1 R,4S)-4- (hydroxymethyl)cyclopent-2-enyl]-9H-purin-2-yl}isobutyramide is removed by stirring with 1 N hydrochloric acid for 2 days at room temperature. The abacavir base, after adjusting the pH to 7.0 and evaporation of the solvent, is finally isolated by trituration and chromatography. Then, it is transformed by reaction with an acid to the corresponding salt of abacavir. The main disadvantages of this method are: (i) the use of a strongly corrosive mineral acid to remove the amino protective group; (ii) the need of a high dilution rate; (iii) a long reaction time to complete the reaction; (iv) the need of isolating the free abacavir; and (v) a complicated chromatographic purification process.

Thus, despite the teaching of this prior art document, the research of new deprotection processes of a N-acylated {(1 S,4R)-4-[2-amino-6- (cyclopropylamino)-9H-purin-9-yl]-cyclopent-2-enyl}methanol is still an active field, since the industrial exploitation of the known process is difficult, as it has pointed out above. Thus, the provision of a new process for the removal of the amino protective group of a N-acylated {(1 S,4R)-4-[2-amino-6-

(cyclopropylamino)-9H-purin-9-yl]-cyclopent-2-enyl}methanol is desirable.

Example 1 : Preparation of abacavir hemisulfate

N-{6-(cyclopropylamino)-9-[(1 R,4S)-4-(hydroxymethyl)cyclopent-2-enyl]-9H- purin-2-yl}isobutyramide (6.56 g, 18.40 mmol) was slurried in a mixture of isopropanol (32.8 ml) and 10% solution of NaOH (36.1 ml, 92.0 mmol). The mixture was refluxed for 1 h. The resulting solution was cooled to 20-25 0C and tert-butyl methyl ether (32.8 ml) was added. The layers were separated and H2SO4 96% (0.61 ml, 11.03 mmol) was added dropwise to the organic layer. This mixture was cooled to 0-50C and the resulting slurry filtered off.

The solid was dried under vacuum at 40 0C. Abacavir hemisulfate (5.98 g, 97%) was obtained as a white powder.

Example 6: Preparation of abacavir

N-{6-(cyclopropylamino)-9-[(1 R,4S)-4-(hydroxymethyl)cyclopent-2-enyl]-9H- purin-2-yl}isobutyramide (1.0 g, 2.80 mmol) was slurried in a mixture of isopropanol (2 ml) and 10% solution of NaOH (1.1 ml, 2.80 mmol). The mixture was refluxed for 1 h. The resulting solution was cooled to 20-25 0C and tert-butyl methyl ether (2 ml) was added. The aqueous layer was discarded, the organic phase was cooled to 0-5 0C and the resulting slurry filtered off. The solid was dried under vacuum at 400C. Abacavir (0.62 g, 77%) was obtained as a white powder.

Example 7: Preparation of abacavir

N-{6-(cyclopropylamino)-9-[(1 R,4S)-4-(hydroxymethyl)cyclopent-2-enyl]-9H- purin-2-yl}isobutyramide (1.25 g, 3.51 mmol) was slurried in a mixture of isopropanol (2.5 ml) and 10% solution of NaOH (1.37 ml, 3.51 mmol). The mixture was refluxed for 1 h and concentrated to dryness. The residue was crystallized in acetone. Abacavir (0.47 g, 47%) was obtained as a white powder.

Example 8: Preparation of abacavir

N-{6-(cyclopropylamino)-9-[(1 R,4S)-4-(hydroxymethyl)cyclopent-2-enyl]-9H- purin-2-yl}isobutyramide (1.25 g, 3.51 mmol) was slurried in a mixture of isopropanol (2.5 ml) and 10% solution of NaOH (1.37 ml, 3.51 mmol). The mixture was refluxed for 1 h and concentrated to dryness. The residue was crystallized in acetonitrile. Abacavir (0.43 g, 43%) was obtained as a white powder.

Example 9: Preparation of abacavir

A mixture of N-{6-(cyclopropylamino)-9-[(1 R,4S)-4-(hydroxymethyl)cyclopent- 2-enyl]-9H-purin-2-yl}isobutyramide (10 g, 28 mmol), isopropanol (100 ml) and 10% solution of NaOH (16.8 ml, 42 mmol) was refluxed for 1 h. The resulting solution was cooled to 20-25 0C and washed several times with 25% solution of NaOH (10 ml). The wet organic layer was neutralized to pH 7.0-7.5 with 17% hydrochloric acid and it was concentrated to dryness under vacuum. The residue was crystallized in ethyl acetate (150 ml) to afford abacavir (7.2 g, 90%).

Example 10: Preparation of abacavir

A mixture of N-{6-(cyclopropylamino)-9-[(1 R,4S)-4-(hydroxymethyl)cyclopent- 2-enyl]-9H-purin-2-yl}isobutyramide (10 g, 28 mmol), isopropanol (100 ml) and 10% solution of NaOH (16.8 ml, 42 mmol) was refluxed for 1 h. The resulting solution was cooled to 20-25 0C and washed several times with 25% solution of NaOH (10 ml). The wet organic layer was neutralized to pH 7.0-7.5 with 17% hydrochloric acid and it was concentrated to dryness under vacuum. The residue was crystallized in acetone (300 ml) to afford abacavir (7.0 g, 88%).

…………………………………

http://www.google.com/patents/WO2004089952A1?cl=en

Abacavir of formula (1) :

Figure imgf000002_0001

or (1 S,4R)-4-[2-Amino-6-(cyclopropylamino)-9H-purin-9-yl]-2-cyclopentene-1 – methanol and its salts are nucleoside reverse transcriptase inhibitors. Abacavir sulfate is a nucleoside reverse transcriptase inhibitor and used in the treatment of human immunodeficiency virus infection. Abacavir sulfate and related compounds and their therapeutic uses are disclosed in US 5,034,394.

Crystalline forms of abacavir sulfate have not been reported in the literature. Moreover, the processes described in the literature do not produce abacavir sulfate in a stable, well-defined and reproducible crystalline form. It has now been discovered that abacavir sulfate can be prepared in three stable, well-defined and consistently reproducible crystalline forms.

Example 1

Abacavir free base (3.0 gm, obtained by the process described in example 21 of US 5,034,394) is dissolved in ethyl acetate (15 ml) and cone, sulfuric acid (0.3 ml) is added to the solution. Then the contents are stirred for 3 hours at 20°C and filtered to give 3.0 gm of form I abacavir sulfate. Example 2 Abacavir free base (3.0 gm) is dissolved in acetone (20 ml) and cone, sulfuric acid (0.3 ml) is added to the solution. Then the contents are stirred for 6 hours at 25°C and filtered to give 2.8 gm of form I abacavir sulfate.

Example 3 Abacavir free base (3.0 gm) is dissolved in acetonitrile (15 ml) and sulfuric acid (0.3 ml) is added to the solution. Then the contents are stirred for 2 hours at 25°C and the separated solid is filtered to give 3.0 gm of form II abacavir sulfate.

Example 4 Abacavir free base (3.0 gm) is dissolved in methyl tert-butyl ether (25 ml) and sulfuric acid (0.3 ml) is added to the solution. Then the contents are stirred for 1 hours at 25°C and the separated solid is filtered to give 3.0 gm of form II abacavir sulfate.

Example 5 Abacavir free base (3.0 gm) is dissolved in methanol (15 ml) and sulfuric acid (0.3 ml) is added to the solution. The contents then are cooled to 0°C and diisopropyl ether (15 ml) is added. The reaction mass is stirred for 2 hours at about 25°C and the separated solid is filtered to give 3.0 gm of form III abacavir sulfate

…………………………….

http://www.google.com.ar/patents/WO1999021861A1?cl=en

The present invention relates to a new process for the preparation of the chiral nucleoside analogue (1S, 4R)-4-[2-amino-6-(cyclopropylamino)-9H purin-9-yl]-2- cyclopentene-1 -methanol (compound of Formula (I)).

The compound of formula (I) is described as having potent activity against human immunodeficiency virus (HIV) and hepatitis B virus (HBV) in EPO34450.

Figure imgf000003_0001

Results presented at the 34th Interscience Conference on Antimicrobial Agents and Chemotherapy (October 4-7, 1994) demonstrate that the compound of formula I has significant activity against HIV comparable to, and if not better than, some current anti HIV drugs, such as zidovudine and didanosine.

Currently the compound of Formula (I) is undergoing clinical investigation to determine its safety and efficacy in humans. Therefore, there exists at the present time a need to supply large quantities of this compound for use in clinical trials.

Current routes of synthesising the compound of formula (I) involve multiple steps and are relatively expensive. It will be noted that the compound has two centres of asymmetry and it is essential that any route produces the compound of formula (I) substantially free of the corresponding enantiomer, preferably the compound of formula (I) is greater than 95% w/w free of the corresponding enantiomer.

Processes proposed for the preparation of the compound of formula (I) generally start from a pyrimidine compound, coupling with a 4-amino-2-cyclopentene-1- methanol analogue, cyciisation to form the imidazole ring and then introduction of the cyclopropylamine group into the 6 position of the purine, such routes include those suggested in EPO434450 and WO9521161. Essentially both routes disclosed in the two prior patent applications involve the following steps:-

(i) coupling (1S, 4R)-4-amino-2-cyclopentene-1 -methanol to N-(4,6-dichloro-5- formamido-2-pyrimidinyl) acetamide or a similar analogue thereof, for example N- (2-amino-4,6-dichloro-5-pyrimidinyl) formamide;

(ii) ring closure of the resultant compound to form the intermediate (1 S, 4R)-4- (2-amino-6-chloro-9H-purin-9-yl)-2-cyclopentene-1 -methanol;

(iii) substituting the halo group by a cyclopropylamino group on the 6 position of the purine ring.

The above routes are multi-step processes. By reducing the number of processing steps significant cost savings can be achieved due to the length of time to manufacture the compound being shortened and the waste streams minimised.

An alternative process suggested in the prior art involves the direct coupling of carbocyclic ribose analogues to the N atom on the 9 position of 2-amino-6-chloro purine. For example WO91/15490 discloses a single step process for the formation of the (1S, 4R)- 4-(2-amino-6-chloro-9H-purin-9-yl)-2-cyclopentene-1- methanol intermediate by reacting (1S, 4R)-4-hydroxy-2-cyclopentene-1 -methanol, in which the allylic hydroxyl group has been activated as an ester or carbonate and the other hydroxyl group has a blocking group attached (for example 1 ,4- bis- methylcarbonate) with 2-amino-6-chloropurine.

However we have found that when synthesising (1S, 4R)-4-(2-amino-6-chloro-9H- purin-9-yl)-2-cyclopentene-1- methanol by this route a significant amount of an N- 7 isomer is formed (i.e. coupling has occurred to the nitrogen at the 7- position of the purine ring) compared to the N-9 isomer desired. Further steps are therefore required to convert the N-7 product to the N-9 product, or alternatively removing the N-7 product, adding significantly to the cost. We have found that by using a transition metal catalysed process for the direct coupling of a compound of formula (II) or (III),

Figure imgf000005_0001

Example 1 (1 S. 4R)-4-[2-Amino-6-(cvclopropylamino)-9H purin-9-vπ-2-cvclopentene-1 – methanol

Triphenylphosphine (14mg) was added, under nitrogen, to a mixture of (1S.4R)- 4-hydroxy-2-cyclopentene -1 -methanol bis(methylcarbonate) (91 mg), 2-amino-6- (cyclopropylamino) purine (90mg), tris(dibenzylideneacetone)dipalladium (12mg) and dry DMF (2ml) and the resulting solution stirred at room temperature for 40 min.

The DMF was removed at 60° in vacuo and the residue partitioned between ethyl acetate (25ml.) and 20% sodium chloride solution (10ml.). The ethyl acetate solution was washed with 20% sodium chloride (2x12ml.) and with saturated sodium chloride solution, then dried (MgSO4) and the solvent removed in vacuo.

The residue was dissolved in methanol (10ml.), potassium carbonate (17mg) added and the mixture stirred under nitrogen for 15h.

The solvent was removed in vacuo and the residue chromatographed on silica gel

(Merck 9385), eluting with dichloromethane-methanol [(95:5) increasing to (90:10)] to give the title compound (53mg) as a cream foam.

δ(DMSO-d6): 7.60 (s.1 H); 7.27 (s,1 H); 6.10 (dt,1 H); 5.86 (dt, 1 H); 5.81 (s,2H); 5.39 (m,1H); 4.75 (t,1H); 3.44 (t,2H); 3.03 (m, 1H): 2.86 (m,1H);2.60 (m,1H); 1.58 (dt, 1 H); 0.65 (m, 2H); 0.57 (m,2H).

TLC SiO2/CHCI3-MeOH (4:1 ) Rf 0.38; det. UN., KMnO4

Trade Names

Page Trade name Manufacturer
Germany Kiveksa GlaxoSmithKline
Trizivir -»-
Ziagen -»-
France Kiveksa -»-
Trizivir -»-
Ziagen -»-
United Kingdom Kiveksa -»-
Trizivir -»-
Ziagen -»-
Italy Trizivir -»-
Ziagen -»-
Japan Épzikom -»-
Ziagen -»-
USA Épzikom -»-
Trizivir -»-
Ziagen -»-
Ukraine Virol Ranbaksi Laboratories Limited, India
Ziagen GlaksoSmitKlyayn Inc.., Canada
Abamun Tsipla Ltd, India
Abacavir sulfate Aurobindo Pharma Limited, India

Formulations

  • Oral solution 20 mg / ml;
  • Tablets of 300 mg (as the sulfate);
  • Trizivir tablets 300 mg – abacavir in fixed combination with 150 mg of lamivudine and 300 mg zidovudine

ZIAGEN is the brand name for abacavir sulfate, a synthetic carbocyclic nucleoside analogue with inhibitory activity against HIV-1. The chemical name of abacavir sulfate is (1S,cis)-4-[2-amino-6-(cyclopropylamino)-9H-purin-9-yl]-2-cyclopentene-1-methanol sulfate (salt) (2:1). Abacavir sulfate is the enantiomer with 1S, 4R absolute configuration on the cyclopentene ring. It has a molecular formula of (C14H18N6O)2•H2SO4 and a molecular weight of 670.76 daltons. It has the following structural formula:

ZIAGEN (abacavir sulfate) Structural Formula Illustration

Abacavir sulfate is a white to off-white solid with a solubility of approximately 77 mg/mL in distilled water at 25°C. It has an octanol/water (pH 7.1 to 7.3) partition coefficient (log P) of approximately 1.20 at 25°C.

ZIAGEN Tablets are for oral administration. Each tablet contains abacavir sulfate equivalent to 300 mg of abacavir as active ingredient and the following inactive ingredients: colloidal silicon dioxide, magnesium stearate, microcrystalline cellulose, and sodium starch glycolate. The tablets are coated with a film that is made of hypromellose, polysorbate 80, synthetic yellow iron oxide, titanium dioxide, and triacetin.

ZIAGEN Oral Solution is for oral administration. Each milliliter (1 mL) of ZIAGEN Oral Solution contains abacavir sulfate equivalent to 20 mg of abacavir (i.e., 20 mg/mL) as active ingredient and the following inactive ingredients: artificial strawberry and banana flavors, citric acid (anhydrous), methylparaben and propylparaben (added as preservatives), propylene glycol, saccharin sodium, sodium citrate (dihydrate), sorbitol solution, and water.

In vivo, abacavir sulfate dissociates to its free base, abacavir. All dosages for ZIAGEN are expressed in terms of abacavir.

History

Abacavir was approved by the Food and Drug Administration (FDA) on December 18, 1998 and is thus the fifteenth approved antiretroviral drug in the United States. Its patent expired in the United States on 2009-12-26.

Links

  • US 5 089 500 (Burroughs Wellcome; 18.2.1992; GB-prior. 27.6.1988).
  1. Synthesis a)
    • EP 434 450 (Wellcome Found .; 26.6.1991; appl. 21.12.1990; prior-USA. 22.12.1989).
    • Crimmins, MT et al .: J. Org. Chem. (JOCEAH) 61 4192 (1996).
    • EP 1 857 458 (Solmag; appl. 5.5.2006).
    • EP 424 064 (Enzymatix; appl. 24.4.1991; GB -prior. 16.10.1989).
    • U.S. 6 340 587 (Beecham SMITHKLINE; 22.1.2002; appl. 20.8.1998; GB -prior. 22.8.1997).
  2. Синтез b)
    • Olivo, HF et al .: J. Chem. Soc., Perkin Trans. 1 (JCPRB4) 1998, 391.
  3. Preparation c)
    • U.S. 5 034 394 (Wellcome Found .; 23.7.1991; appl. 22.12.1989; GB -prior. 27.6.1988).
  4. Synthesis d)
    • WO 9 924 431 (Glaxo; appl. 12.11.1998; WO-prior. 12.11.1997).

WO2008037760A1 * Sep 27, 2007 Apr 3, 2008 Esteve Quimica Sa Process for the preparation of abacavir
EP1905772A1 * Sep 28, 2006 Apr 2, 2008 Esteve Quimica, S.A. Process for the preparation of abacavir
US8183370 Sep 27, 2007 May 22, 2012 Esteve Quimica, Sa Process for the preparation of abacavir
EP0434450A2 21 Dec 1990 26 Jun 1991 The Wellcome Foundation Limited Therapeutic nucleosides
EP0741710A1 3 Feb 1995 13 Nov 1996 The Wellcome Foundation Limited Chloropyrimide intermediates
WO1998052949A1 14 May 1998 26 Nov 1998 Glaxo Group Ltd Carbocyclic nucleoside hemisulfate and its use in treating viral infections
WO1999021861A1 24 Oct 1997 6 May 1999 Glaxo Group Ltd Process for preparing a chiral nucleoside analogue
WO1999039691A2 * 4 Feb 1999 12 Aug 1999 Brooks Nikki Thoennes Pharmaceutical compositions
WO2008037760A1 * 27 Sep 2007 3 Apr 2008 Esteve Quimica Sa Process for the preparation of abacavir

References

  1. Jump up^ SFGate.com
  2. Jump up^ “WHO Model List of EssentialMedicines”. World Health Organization. October 2013. Retrieved 22 April 2014.
  3. Jump up^ https://online.epocrates.com/noFrame/showPage.do?method=drugs&MonographId=2043&ActiveSectionId=5
  4. Jump up^ Mallal, S., Phillips, E., Carosi, G. et al. (2008). “HLA-B*5701 screening for hypersensitivity to abacavir”. New England Journal of Medicine 358: 568–579.doi:10.1056/nejmoa0706135.
  5. Jump up^ Rauch, A., Nolan, D., Martin, A. et al. (2006). “Prospective genetic screening decreases the incidence of abacavir hypersensitivity reactions in the Western Australian HIV cohort study”. Clinical Infectious Diseases 43: 99–102. doi:10.1086/504874.
  6. Jump up^ Heatherington et al. (2002). “Genetic variations in HLA-B region and hypersensitivity reactions to abacavir”. Lancet 359: 1121–1122.
  7. Jump up^ Mallal et al. (2002). “Association between presence of HLA*B5701, HLA-DR7, and HLA-DQ3 and hypersensitivity to HIV-1 reverse-transcriptase inhibitor abacavir”. Lancet359: 727–732. doi:10.1016/s0140-6736(02)07873-x.
  8. Jump up^ Rotimi, C.N.; Jorde, L.B. (2010). “Ancestry and disease in the age of genomic medicine”. New England Journal of Medicine 363: 1551–1558.
  9. Jump up^ Phillips, E., Mallal, S. (2009). “Successful translation of pharmacogenetics into the clinic”. Molecular Diagnosis & Therapy 13: 1–9. doi:10.1007/bf03256308.
  10. Jump up^ Phillips, E., Mallal S. (2007). “Drug hypersensitivity in HIV”. Current Opinion in Allergy and Clinical Immunology 7: 324–330. doi:10.1097/aci.0b013e32825ea68a.
  11. Jump up^http://www.fda.gov/drugs/drugsafety/postmarketdrugsafetyinformationforpatientsandproviders/ucm123927.htmAccessed November 29, 2013.
  12. Jump up^ http://dailymed.nlm.nih.gov/dailymed/lookup.cfm?setid=ca73b519-015a-436d-aa3c-af53492825a1
  13. Jump up^ Martin MA, Hoffman JM, Freimuth RR et al. (May 2014). “Clinical Pharmacogenetics Implementation Consortium Guidelines for HLA-B Genotype and Abacavir Dosing: 2014 update”. Clin Pharmacol Ther. 95 (5): 499–500. doi:10.1038/clpt.2014.38.PMC 3994233. PMID 24561393.
  14. Jump up^ Swen JJ, Nijenhuis M, de Boer A et al. (May 2011). “Pharmacogenetics: from bench to byte–an update of guidelines”. Clin Pharmacol Ther. 89 (5): 662–73.doi:10.1038/clpt.2011.34. PMID 21412232.
  15. Jump up^ Shear, N.H., Milpied, B., Bruynzeel, D.P. et al. (2008). “A review of drug patch testing and implications for HIV clinicians”. AIDS 22: 999–1007.doi:10.1097/qad.0b013e3282f7cb60.
  16. Jump up^ http://www.drugs.com/fda/abacavir-ongoing-safety-review-possible-increased-risk-heart-attack-12914.html Accessed November 29, 2013.
  17. Jump up^ Ding X, Andraca-Carrera E, Cooper C et al. (December 2012). “No association of abacavir use with myocardial infarction: findings of an FDA meta-analysis”. J Acquir Immune Defic Syndr. 61 (4): 441–7. doi:10.1097/QAI.0b013e31826f993c.PMID 22932321.
  18.  Illing PT et al. 2012, Nature, doi:10.1038/nature11147

External links

EXTRA INFO

How to obtain carbocyclic nucleosides?

Carbocyclic nucleosides are synthetically the most challenging class of nucleosides, requiring multi-step and often elaborate synthetic pathways to introduce the necessary stereochemistry. There are two main strategies for the preparation of carbocyclic nucleosides. In the linear approach a cyclopentylamine is used as starting material and the heterocycle is built in a stepwise manner (see Scheme 1).

Scheme 1: Linear approach for the synthesis of abacavir.[5]

The more flexible strategy is a convergent approach: a functionalized carbocyclic moiety is condensed with a heterocycle rapidly leading to a variety of carbocyclic nucleosides. Initially, we started our syntheses from cyclopentadiene 1 that is deprotonated and alkylated with benzyloxymethyl chloride to give the diene 2. This material is converted by a hydroboration into cyclopentenol 3 or isomerized into two thermodynamically more stable cyclopentadienes 4a,b. With the protection and another hydroboration step to 5 we gain access to an enantiomerically pure precursor for the synthesis of a variety of carbocyclic 2’-deoxynucleosides e.g.:carba-dT, carba-dA or carba-BVDU.[6] The isomeric dienes 4a,b were hydroborated to the racemic carbocyclic moiety 6.

Scheme 2: Convergent approach for the synthesis of carba-dT.

 

The asymmetric synthesis route and the racemic route above are short and efficient ways to diverse carbocyclic D- or L-nucleosides (Scheme 2). Different heterocycles can be condensed to these precursors leading to carbocyclic purine- and pyrimidine-nucleosides. Beside α- and β-nucleosides, carbocyclic epi– andiso-nucleosides in the 2’-deoxyxylose form were accessable.[7]

What else is possible? The racemic cyclopentenol 6 can be coupled by a modified Mitsunobu-reaction.Moreover, this strategy offers the possibility of synthesizing new carbocyclic nucleosides by functionalizing the double bond before or after introduction of the nucleobase (scheme 3).[8]

Scheme 3: Functionalized carbocyclic nucleosides based on cyclopentenol 6.

Other interesting carbocyclic precursors like cyclopentenol 7 can be used to synthesize several classes of carbocyclic nucleoside analogues, e.g.: 2’,3’-dideoxy-2’,3’-didehydro nucleosides (d4-nucleosides), 2’,3’-dideoxynucleosides (ddNs), ribonucleosides, bicyclic nucleosides or even 2’-fluoro-nucleosides.

Scheme 4: Functionalized carbocyclic thymidine analogues based on cyclopentenol 7.

[1]        V. E. Marquez, T. Ben-Kasus, J. J. Barchi, K. M. Green, M .C. Nicklaus, R. Agbaria, J. Am.  Chem. Soc.2004,126, 543.

[2]        A. D. Borthwick, K. Biggadike, Tetrahedron 1992, 48, 571.

[3]        H. Bricaud, P. Herdewijn, E. De Clercq,  Biochem. Pharmacol. 1983, 3583.

[4]        P. L. Boyer, B. C. Vu, Z. Ambrose, J. G. Julias, S. Warnecke, C. Liao, C. Meier, V. E. Marquez, S. H. Hughes, J. Med. Chem. 2009, 52, 5356.

[5]        S. M. Daluge, M. T. Martin, B. R. Sickles, D. A. Livingston, Nucleosides, Nucleotides Nucleic Acids 2000,19, 297.

[6]        O. R. Ludek, C. Meier, Synthesis 2003, 2101.

[7]        O. R. Ludek, T. Kraemer, J. Balzarini, C. Meier, Synthesis 2006, 1313.

[8]        M. Mahler, B. Reichardt, P. Hartjen, J. van Lunzen, C. Meier, Chem. Eur. J. 2012, 18, 11046-11062.

FDA approves new treatment for hospital-acquired and ventilator-associated bacterial pneumonia


The U.S. Food and Drug Administration today approved a new indication for the previously FDA-approved drug, Zerbaxa (ceftolozane and tazobactam) for the treatment of hospital-acquired bacterial pneumonia and ventilator-associated bacterial pneumonia (HABP/VABP) in patients 18 years and older. The FDA initially approved Zerbaxa in 2014 to treat complicated intra-abdominal infections and for complicated urinary tract infections.

“A key global challenge we face as a public health agency is addressing the threat of antimicrobial-resistant infections,” said FDA Principal Deputy Commissioner Amy Abernethy, M.D., Ph.D. “Hospital-acquired and ventilator-associated bacterial pneumonia are serious infections that can result in death in some patients. New therapies to treat these infections are important to …

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June 03, 2019

The U.S. Food and Drug Administration today approved a new indication for the previously FDA-approved drug, Zerbaxa (ceftolozane and tazobactam) for the treatment of hospital-acquired bacterial pneumonia and ventilator-associated bacterial pneumonia (HABP/VABP) in patients 18 years and older. The FDA initially approved Zerbaxa in 2014to treat complicated intra-abdominal infections and for complicated urinary tract infections.

“A key global challenge we face as a public health agency is addressing the threat of antimicrobial-resistant infections,” said FDA Principal Deputy Commissioner Amy Abernethy, M.D., Ph.D. “Hospital-acquired and ventilator-associated bacterial pneumonia are serious infections that can result in death in some patients. New therapies to treat these infections are important to meet patient needs because of increasing antimicrobial resistance. That’s why, among our other efforts to address antimicrobial resistance, we’re focused on facilitating the development of safe and effective new treatments to give patients more options to fight life-threatening infections.”

HABP/VABP occur in patients in hospitals or other health care facilities and can be caused by a variety of bacteria. According to data from the U.S. Centers for Disease Control and Prevention, HABP and VABP are currently the second most common type of hospital-acquired infection in the United States, and are a significant issue in patients in the intensive care unit (ICU).

The safety and efficacy of Zerbaxa for the treatment of HABP/VABP, administered via injection, was demonstrated in a multinational, double-blind study that compared Zerbaxa to another antibacterial drug in 726 adult patients hospitalized with HABP/VABP. The study showed that mortality and cure rates were similar between Zerbaxa and the comparator treatment.

The most common adverse reactions observed in the HABP/VABP trial among patients treated with Zerbaxa were elevated liver enzyme levels, renal impairment or failure, and diarrhea.
Zerbaxa should not be used in patients with known serious hypersensitivity to components of Zerbaxa, as well as hypersensitivity to piperacillin/tazobactam or other members of the beta lactam class of antibacterial drugs.

Zerbaxa received FDA’s Qualified Infectious Disease Product (QIDP) designation for the treatment of HABP/VABP. The QIDP designation is given to antibacterial and antifungal drug products intended to treat serious or life-threatening infections under the Generating Antibiotic Incentives Now (GAIN) title of the FDA Safety and Innovation Act. As part of QIDP designation, the Zerbaxa marketing application for the HABP/VABP indication was granted Priority Review under which the FDA’s goal is to take action on an application within an expedited time frame.

The FDA granted the approval of Zerbaxa for the treatment of HABP/VABP to Merck & Co., Inc.

//////////////ceftolozane,  tazobactam, FDA 2019,  Zerbaxa,  HABP/VABP, Merck , Qualified Infectious Disease Product,  (QIDP),  Priority Review

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