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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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Ipragliflozin


Ipragliflozin

ASP-1941 ,   1(S)-[3-(1-benzothien-2-ylmethyl)-4-fluorophenyl]-1-deoxy-beta-D-glucopyranose L-proline cocrystal

Kotobuki (Originator)

(1S)-1,5-Anhydro-1-C-[3-[(1-benzothiophen-2-yl)methyl]-4-fluorophenyl]-D-glucitol
Molecular Formula C21H21FO5S
Molecular Weight 404.45
CAS Registry Number 761423-87-4

Ipragliflozin (formerly ASP1941) has been filed in Japan on the back of phase III trials which showed that it could provide significant reductions in glycated haemoglobin levels (HbA1c) levels – a marker of glucose control over time – compared to placebo

According to Astellas’ latest R&D pipeline update in February 2013, Astellas is developing ipragliflozin only in Japan. The same document in August 2012 indicated it was also carrying out phase II studies with the drug in the US and Japan.

Astellas Pharma Inc.: Submits Application for Marketing Approval of
Ipragliflozin (ASP1941), SGLT2 Inhibitor for Treatment of
Type 2 Diabetes, in Japan
TOKYO, March 13, 2013 – Astellas Pharma Inc. (“Astellas”; Tokyo:4503; President and CEO:
Yoshihiko Hatanaka) announced today that it has submitted a market authorization application for aSGLT2 inhibitoripragliflozin (generic name; development code: ASP1941) to the Ministry of Health, Labour and Welfare in Japan seeking an approval forthe indication of type 2 diabetes.
Ipragliflozin is a selective SGLT2 (sodium-glucose co-transporter 2)inhibitor discovered through research collaboration with Kotobuki Pharmaceutical Co., Ltd. SGLTs are membrane proteins that
exist on the cell surface and transfer glucose into cells. SGLT2 is a subtype of the sodium-glucose co-transporters and plays a key role in the reuptake of glucose in the proximal tubule of the kidneys.
Ipragliflozin reduces blood glucose levels by inhibiting the reuptake of glucose.
In the Phase III pivotal study in monotherapy for type 2 diabetesin Japan, ipragliflozin
demonstrated significant decreases of HbA1c, an index of glycemic control, in change from baseline compared to placebo. Based on the safety resultsin this study, ipragliflozin was safe and well tolerated. Patients with type 2 diabetes generally need combination therapy, so it is important
for a novel oral hypoglycemic agent to be safe to use with existing diabetes therapies. In this regard, Astellas has conducted six Phase III studies to investigate the safety and efficacy of ipragliflozin
used in combination with other hypoglycemic agentsfor a long term period. In these Phase IIIstudies, effectiveness and favorable safety of ipragliflozin was confirmed even in combination with
other hypoglycemic agents.
Astellas expects to provide an additional therapeutic option and further contribute to the treatment of type 2 diabetes by introducing ipragliflozin, an oral hypoglycemic agent with a novel mechanism
of action, into the Japanese market.
About Type 2 Diabetes
Diabetes (medically known as diabetes mellitus) is a disorder in which the body has difficulty regulating its blood glucose (sugar) level. There are two major types of diabetes: type 1 and type 2.
Type 2 diabetes (formerly called non-insulin-dependent diabetes mellitus or adult-onset diabetes) is a disorder that is characterized by high blood glucose in the context of insulin resistance and relative insulin deficiency. Patients are instructed to increase exercise and diet restrictions, but most
require treatment with an anti-diabetic agent to control blood glucose.

structure:

Figure US20130035281A1-20130207-C00015

The compound and methods of its synthesis are described in WO 2004/080990, WO 2005/012326 and WO 2007/114475 for example.

The gluconolactone method: In 1988 and 1989 a general method was reported to prepare C-arylglucosides from tetra-6>-benzyl protected gluconolactone, which is an oxidized derivative of glucose (see J. Org. Chem. 1988, 53, 752-753 and J. Org. Chem. 1989, 54, 610- 612). The method comprises: 1) addition of an aryllithium derivative to the hydroxy-protected gluconolactone to form a hemiketal (a.k.ci., a lactol), and 2) reduction of the resultant hemiketal with triethylsilane in the presence of boron trifluoride etherate. Disadvantages of this classical, but very commonly applied method for β-C-arylglucoside synthesis include:

1) poor “redox economy” (see J. Am. Chem. Soc. 2008, 130, 17938-17954 and Anderson, N. G. Practical Process Research & Development, 1st Ed.; Academic Press, 2000 (ISBN- 10: 0120594757); pg 38)— that is, the oxidation state of the carbon atom at CI, with respect to glucose, is oxidized in the gluconolactone and then following the arylation step is reduced to provide the requisite oxidation state of the final product. 2) due to a lack of stereospecificity, the desired β-C-arylglucoside is formed along with the undesired a-C-arylglucoside stereoisomer (this has been partially addressed by the use of hindered trialkylsilane reducing agents (see Tetrahedron: Asymmetry 2003, 14, 3243-3247) or by conversion of the hemiketal to a methyl ketal prior to reduction (see J. Org. Chem. 2007, 72, 9746-9749 and U.S. Patent 7,375,213)).

Oxidation Reduction

Figure imgf000004_0001

Glucose Gluconoloctone Hemiketal a-anomer β-anomer

R = protecting group

The metalated glucal method: U.S. Patent 7,847,074 discloses preparation of SGLT2 inhibitors that involves the coupling of a hydroxy-protected glucal that is metalated at CI with an aryl halide in the presence of a transition metal catalyst. Following the coupling step, the requisite formal addition of water to the C-arylglucal double bond to provide the desired C-aryl glucoside is effected using i) hydroboration and oxidation, or ii) epoxidation and reduction, or iii) dihydroxylation and reduction. In each case, the metalated glucal method represents poor redox economy because oxidation and reduction reactions must be conducted to establish the requisite oxidation states of the individual CI and C2 carbon atoms.

U.S. Pat. Appl. 2005/0233988 discloses the utilization of a Suzuki reaction between a CI -boronic acid or boronic ester substituted hydroxy-protected glucal and an aryl halide in the presence of a palladium catalyst. The resulting 1- C-arylglucal is then formally hydrated to provide the desired 1- C-aryl glucoside skeleton by use of a reduction step followed by an oxidation step. The synthesis of the boronic acid and its subsequent Suzuki reaction, reduction and oxidation, together, comprise a relatively long synthetic approach to C-arylglucosides and exhibits poor redox economy. Moreover, the coupling catalyst comprises palladium which is toxic and therefore should be controlled to very low levels in the drug substance.

Figure imgf000004_0002

R = protecting group; R’ = H or alkyl

The glucal epoxide method: U.S. Patent 7,847,074 discloses a method that utilizes an organometallic (derived from the requisite aglycone moiety) addition to an electrophilic epoxide located at C1-C2 of a hydroxy-protected glucose ring to furnish intermediates useful for SGLT2 inhibitor synthesis. The epoxide intermediate is prepared by the oxidation of a hydroxy- protected glucal and is not particularly stable. In Tetrahedron 2002, 58, 1997-2009 it was taught that organometallic additions to a tri-6>-benzyl protected glucal-derived epoxide can provide either the a-C-arylglucoside, mixtures of the a- and β-C-arylglucoside or the β-C-arylglucoside by selection of the appropriate counterion of the carbanionic aryl nucleophile (i.e., the

organometallic reagent). For example, carbanionic aryl groups countered with copper (i.e., cuprate reagents) or zinc (i.e., organozinc reagents) ions provide the β-C-arylglucoside, magnesium ions provide the a- and β-C-arylglucosides, and aluminum (i.e., organoaluminum reagents) ions provide the a-C-arylglucoside.

Figure imgf000005_0001

or Zn

The glycosyl leaving group substitution method: U.S. Patent 7,847,074, also disclosed a method comprising the substitution of a leaving group located at CI of a hydroxy-protected glucosyl species, such as a glycosyl halide, with a metalated aryl compound to prepare SGLT2 inhibitors. U.S. Pat. Appl. 2011/0087017 disclosed a similar method to prepare the SGLT2 inhibitor canagliflozin and preferably diarylzinc complexes are used as nucleophiles along with tetra- >-pivaloyl protected glucosylbromide.

Figure imgf000005_0002

Glucose Glucosyl bromide β-anomer

Methodology for alkynylation of 1,6-anhydroglycosides reported in Helv. Chim. Acta. 1995, 78, 242-264 describes the preparation of l,4-dideoxy-l,4-diethynyl^-D-glucopyranoses (a. La., glucopyranosyl acetylenes), that are useful for preparing but-l,3-diyne-l,4-diyl linked polysaccharides, by the ethynylating opening (alkynylation) of partially protected 4-deoxy-4-C- ethynyl-l,6-anhydroglucopyranoses. The synthesis of β-C-arylglucosides, such as could be useful as precursors for SLGT2 inhibitors, was not disclosed. The ethynylation reaction was reported to proceed with retention of configuration at the anomeric center and was rationalized (see Helv. Chim. Acta 2002, 85, 2235-2257) by the C3-hydroxyl of the 1,6- anhydroglucopyranose being deprotonated to form a C3-0-aluminium species, that coordinated with the C6-oxygen allowing delivery of the ethyne group to the β-face of the an oxycarbenium cation derivative of the glucopyranose. Three molar equivalents of the ethynylaluminium reagent was used per 1 molar equivalent of the 1,6-anhydroglucopyranose. The

ethynylaluminium reagent was prepared by the reaction of equimolar (i.e., 1:1) amounts of aluminum chloride and an ethynyllithium reagent that itself was formed by the reaction of an acetylene compound with butyllithium. This retentive ethynylating opening method was also applied (see Helv. Chim. Acta. 1998, 81, 2157-2189) to 2,4-di-<9-triethylsilyl- 1,6- anhydroglucopyranose to provide l-deoxy-l-C-ethynyl- -D-glucopyranose. In this example, 4 molar equivalents of the ethynylaluminium reagent was used per 1 molar equivalent of the 1,6- anhydroglucopyranose. The ethynylaluminium regent was prepared by the reaction of equimolar (i.e., 1: 1) amounts of aluminum chloride and an ethynyl lithium reagent that itself was formed by reaction of an acetylene compound with butyllithium.

It can be seen from the peer-reviewed and patent literature that the conventional methods that can be used to provide C-arylglucosides possess several disadvantages. These include (1) a lack of stereoselectivity during formation of the desired anomer of the C- arylglucoside, (2) poor redox economy due to oxidation and reduction reaction steps being required to change the oxidation state of CI or of CI and C2 of the carbohydrate moiety, (3) some relatively long synthetic routes, (4) the use of toxic metals such as palladium, and/or (5) atom uneconomic protection of four free hydroxyl groups. With regard to the issue of redox economy, superfluous oxidation and reduction reactions that are inherently required to allow introduction of the aryl group into the carbohydrate moiety of the previously mention synthetic methods and the subsequent synthetic steps to establish the required oxidation state, besides adding synthetic steps to the process, are particular undesirable for manufacturing processes because reductants can be difficult and dangerous to operate on large scales due to their flammability or ability to produce flammable hydrogen gas during the reaction or during workup, and because oxidants are often corrosive and require specialized handling operations (see Anderson, N. G. Practical Process Research & Development, 1st Ed.; Academic Press, 2000 (ISBN-10: 0120594757); pg 38 for discussions on this issue).

  • The C-glycoside derivative represented by the formula (1) and its salt [hereinafter, they are referred to as “compound (1)” or “compound of formula (1)” in some cases] is known to be useful for treatment and prevention of diabetes such as insulin-dependent diabetes (type 1 diabetes), non-insulin-dependent diabetes (type 2 diabetes) and the like and various diabetes-related diseases including insulin-resistant diseases and obesity (Patent Literature 1).
  • Figure imgb0001
    Figure imgb0002
  • The method for producing the C-glycoside derivative represented by the formula (1), described in the Patent Literature 1 is understood to be represented by the below-shown reaction formula (I), by referring to the Examples and Reference Examples, described in the Patent Literature 1. Roughly explaining, it is a method which comprises reacting [1-benzothien-2-yl(5-bromo-2-fluorophenyl)methoxy]tert-butyl)dimethylsilane (synthesized in accordance with Reference Example 37 of the Literature) in a manner shown in Example 65 of the Literature, to obtain (1S)-1,5-anhydro-1-[3-(1-benzothien-2-ylmethyl)-4-fluorophenyl]-2,3,4,6-tetra-O-benzyl-D-glucitol and then reacting the obtained compound in accordance with Example 100 of the Literature to synthesize intended (1S)-1,5-anhydro-1-C-[3-(1-benzothiophene-2-ylmethyl)-4-fluorophenyl]-D-glucitol.
  • Figure imgb0003
    Figure imgb0004
  • However, the method for producing the C-glycoside derivative of the formula (1), disclosed in the Patent Literature 1 is not industrially satisfactory in yield and cost, as is seen in later-shown Reference Example 1 of the present Description.
  • For example, as described later, the method includes a step of low product yield (for example, a step of about 50% or lower yield) and the overall yield of the C-glycoside derivative (final product) represented by the formula (1) from the compound (8) (starting raw material) is below 7%; therefore, the method has problems in yield and cost from the standpoint of medicine production and has not been satisfactory industrially. In addition, the method includes an operation of purification by column chromatography which uses chloroform as part of purification solvents; use of such a solvent poses a problem in environmental protection and there are various restrictions in industrial application of such an operation; thus, the method has problems in providing an effective medicine.
  • Also, an improved method of conducting an addition reaction with trimethylsilyl carbohydrate instead of benzyl carbohydrate and then conducting deprotection for acetylation, is known for a compound which has a structure different from that of the compound of the formula (1) but has a structure common to that of the compound of the formula (1) (Patent Literature 2). It is described in the Patent Literature 2 that the improved method enhances the overall yield to 6.2% from 1.4%. Even in the improved method, however, the yield is low at 6.2% which is far from satisfaction in industrial production.

Figure imgb0022

http://www.google.com/patents/EP2105442A1

      First step: synthesis of 1-benzothien-2-yl(5-bromo-2-fluorophenyl)methanol

    • Into a tetrahydrofuran (20 ml) solution of benzo[b]thiophene (5.0 g) was dropwise added a n-hexane solution (25 ml) of n-butyl lithium (1.58 M) at -78°C in an argon atmosphere, followed by stirring at -78°C for 10 minutes. Into this solution was dropwise added a tetrahydrofuran (80 ml) solution of 5-bromo-2-fluorobenzaldehyde (8.0 g), followed by stirring at -78°C for 2.5 hours. The temperature of the reaction mixture was elevated to room temperature. Water was added thereto, followed by extraction with ethyl acetate. The organic layer was washed with a saturated aqueous sodium chloride solution, dried over anhydrous magnesium sulfate, filtered, and concentrated. The residue was purified by silica gel column chromatography (n-hexane/ethyl acetate) to obtain 1-benzothien-2-yl(5-bromo-2-fluorophenyl)methanol (10.5 g, yield: 83.6%).
      1H-NMR (CDCl3): δ
      2.74 (1H, d), 6.35 (1H, d), 6.93 (1H, dd), 7.14 (1H, s), 7.27-7.38 (2H, m), 7.39 (1H, m), 7.68 (1H, dd), 7.74 (2H, m)

Second step: synthesis of [1-benzothien-2-yl(5-bromo-2-fluorophenyl)methoxy](tert-butyl)dimethylsilane

    • To a dimethylformamide (20 ml) solution of 1-benzothien-2-yl(5-bromo-2-fluorophenyl)methanol (5.0 g) were added imidazole (1.3 g), a catalytic amount of 4-(dimethylamino)pyridine and tert-butyldimethylchlorosilane (2.7 g), followed by stirring at room temperature for 7 hours. To the reaction mixture was added a saturated aqueous ammonium chloride solution, followed by extraction with ethyl acetate. The organic layer was washed with a saturated aqueous ammonium chloride solution and a saturated aqueous sodium chloride solution, dried over anhydrous magnesium sulfate, filtered and concentrated. The residue was purified by silica gel column chromatography (n-hexane/ethyl acetate) to obtain [1-benzothien-2-yl(5-bromo-2-fluorophenyl)methoxy](tert-butyl)dimethylsilane (5.22 g, yield: 78.0%).
      MS: 451 (M+)
      1H-NMR (CDCl3): δ
      0.05 (3H, s), 0.11 (3H, s), 0.95 (9H, s), 6.34 (1H, s), 6.91 (1H, t), 7.08 (1H, d), 7.23-7.38 (2H, m), 7.64-7.68 (1H, m), 7.75-7.28 (2H, m)

Third step: Synthesis of 1-C-[3-(1-benzothien-2-yl{[tert-butyl-(dimethyl)silyloxy}methyl)4-fluorophenyl]-2,3,4,6-tetra-O-benzyl-D-glucopyranose

    • Into a tetrahydrofuran (15 ml) solution of [1-benzothien-2-yl(5-bromo-2-fluorophenyl)methoxy](tert-butyl)dimethylsilane (1.5 g) was dropwise added a n-hexane solution (2.2 ml) of n-butyl lithium (1.58 M) in an argon atmosphere at -78°C, followed by stirring at -78°C for 30 minutes. Into the solution was dropwise added a tetrahydrofuran (20 ml) solution of 2,3,4,6-tetra-O-benzyl-D-glucono-1,5-lactone (1.9 g), followed by stirring at -78°C for 15 minutes and then at 0°C for 1.5 hours. To the reaction mixture was added a saturated aqueous ammonium chloride solution, followed by extraction with ethyl acetate. The organic layer was washed with a saturated aqueous ammonium chloride solution and a saturated aqueous sodium chloride solution, dried over anhydrous magnesium sulfate, filtered and concentrated. The residue was purified by silica gel column chromatography (n-hexane/chloroform/acetone) to obtain 1-C-[3-(1-benzothien-2-yl{[tert-butyl-(dimethyl)silyloxy}methyl)-4-fluorophenyl]-2,3,4,6-tetra-O-benzyl-D-glucopyranose (1.52 g, yield: 50.2%). MS: 933 (M+Na)

Fourth step: Synthesis of 1-C-{3-[1-benzothien-2-yl(hydroxy)methyl]-4-fluorophenyl}-2,3,4,6-tetra-O-benzyl-D-glucopyranose

    • To a tetrahydrofuran (15 ml) solution of 1-C-[3-(1-benzothien-2-yl{[tert-butyl-(dimethyl)silyloxy}methyl)-4-fluorophenyl]-2,3,4,6-tetra-O-benzyl-D-glucopyranose (1.52 g) was added a tetrahydrofuran solution (2.0 ml) of tetrabutylammonium fluoride (1.0 M), followed by stirring at room temperature for 1 hour. The reaction mixture was concentrated per se. The residue was purified by silica gel column chromatography (n-hexane/ethyl acetate) to obtain 1-C-{3-[1-benzothien-2-yl(hydroxy)methyl]-4-fluorophenyl}-2,3,4,6-tetra-O-benzyl-D-glucopyranose (0.99 g, yield: 74.7%). MS: 819 (M+Na), 779 (M+H-H2O)

Fifth step: Synthesis of (1S)-1,5-anhydro-1-[3-(1-benzothien-2-ylmethyl)-4-fluorophenyl]-2,3,4,6-tetra-O-benzyl-D-glucitol

    • To an acetonitrile (5.0 ml) solution of 1-C-{3-[1-benzothien-2-yl(hydroxy)methyl]-4-fluorophenyl}-2,3,4,6-tetra-O-benzyl-D-glucopyranose (500 mg) were added triethylsilane (175 mg) and boron trifluoride-diethyl ether complex (196 mg) in an argon atmosphere at -20°C, followed by stirring at -20°C for 5 hours. To the reaction mixture was added a saturated aqueous sodium bicarbonate solution, followed by extraction with chloroform. The organic layer was washed with a saturated aqueous sodium bicarbonate solution and a saturated aqueous sodium chloride solution, dried over anhydrous magnesium sulfate, filtered and concentrated. The residue was purified by silica gel column chromatography (n-hexane/ethyl acetate) to obtain (1S)-1,5-anhydro-1-[3-(1-benzothien-2-ylmethyl)-4-fluorophenyl]-2,3,4,6-tetra-O-benzyl-D-glucitol (150 mg, yield: 30.2%) MS: 787 (M+Na)
      1H-NMR (CDCl3): δ
      3.42-3.48 (1H, m), 3.55-3.58 (1H, m), 3.72-3.78 (4H, m), 3.83 (1H, d), 4.14-4.30 (3H, m), 4.39 (1H, d), 4.51-4.67 (4H, m), 4.83-4.94 (2H, m), 6.86-6.90 (1H, m), 6.98 (1H, brs), 7.06-7.37 (24H, m), 7.57-7.60 (1H, m), 7.66-7.69 (1H, m)

Sixth step: Synthesis of (1S)-1,5-anhydro-1-C-[3-(1-benzothiophene-2-ylmethyl)-4-fluorophenyl]-D-glucitol

  • To a dichloromethane (10 ml) solution of (1S)-1,5-anhydro-1-[3-(1-benzothien-2-ylmethyl)-4-fluorophenyl]-2,3,4,6-tetra-O-benzyl-D-glucitol (137 mg) were added pentamethylbenzene (382 mg) and a n-heptane solution (0.75 ml) of boron trichloride (1.0 M) in an argon atmosphere at -78°C, followed by stirring at -78°C for 3 hours. Methanol was added to the reaction mixture, the temperature of the resulting mixture was elevated to room temperature, and the mixture was concentrated per se. The residue was purified by silica gel column chromatography (chloroform/methanol) to obtain (1S)-1,5-anhydro-1-C-[3-(1-benzothiophene-2-ylmethyl)-4-fluorohenyl]-D-glucitol  OR IPRAGLIFLOZIN (63 mg, yield: 87.8%).
    1H-NMR (CD3OD): δ
    3.29-3.48 (4H, m), 3.68 (1H, dd), 3.87 (1H, dd), 4.11 (1H, d), 4.20-4.29 (2H, m), 7.03 (1H, s), 7.08 (1H, dd), 7.19-7.29 (2H, m), 7.35 (1H, m), 7.42 (1H, dd), 7.64 (1H, d), 7.72 (1H, d)

Figure imgb0002

(1S)-1,5-anhydro-1-C-[3-(1-benzothiophene-2-ylmethyl)-4-fluorohenyl]-D-glucitol OR IPRAGLIFLOZIN

http://www.google.com/patents/EP2105442A1

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Empagliflozin



Empagliflozin

BI-10773

(2S,3R,4R,5S,6R)-2-[4-chloro-3-[[4-[(3S)-oxolan-3-yl]oxyphenyl]methyl]phenyl]-6-(hydroxymethyl)oxane-3,4,5-triol

864070-44-0

M.Wt: 450.91
: C23H27ClO7

Sponsor/Developer: Eli Lilly and Boehringer Ingelheim

Mechanism of action: SGLT 2 inhibitor

Indication (Phase): Oral treatment of adults with type 2 diabetes (Phase III, expected to conclude by year’s end); Oral treatment of adults with type 2 diabetes plus high blood pressure (Phase IIb; trial results released Oct. 2)

NDA, MAA filings planned for 2013

Empagliflozin is a potent, selective sodium glucose co-transporter-2 inhibitor that is in development for the treatment of type 2 diabetes. Empagliflozin is an inhibitor of the sodium glucose co-transporter-2 (SGLT-2), which is found almost exclusively in the proximal tubules of nephronic components in the kidneys. SGLT-2 accounts for about 90 percent of glucose reabsorption into the blood. Blocking SGLT-2 causes blood glucose to be eliminated through the urine via the urethra. The Empagliflozin phase III clinical trial program will include about 14,500 patients. The program consists of twelve ongoing international phase III clinical trials, including a large cardiovascular outcomes trial.

Empagliflozin is a novel SGLT2 inhibitor that is described for the treatment or improvement in glycemic control in patients with type 2 diabetes mellitus, for example in WO 05/092877, WO 06/117359, WO 06/120208, WO 2010/092126, WO 2010/092123, WO 2011/039107, WO 2011/039108. The use of a SGLT2 inhibitor in a method for treating obesity is described in WO 08/116,195

WO2005/092877

US20130137646

WO2006/117359 MP 149 DEG CENT

Empagliflozin is drug which is being investigated in clinical trials for the oral treatment oftype 2 diabetes by Boehringer Ingelheim and Eli Lilly and Company.[1][2] It is an inhibitor of the sodium glucose co-transporter-2 (SGLT-2), which is found almost exclusively in theproximal tubules of nephronic components in the kidneys. SGLT-2 accounts for about 90 percent of glucose reabsorption into the blood. Blocking SGLT-2 causes blood glucose to be eliminated through the urine via the urethra.[3][4]

SGLT-2 inhibitors such as empagliflozin reduce blood glucose by blocking glucose reabsorption in the kidney and thereby excreting glucose (i.e., blood sugar) via the urine.[5]

As of December 2013, empagliflozin is in phase III clinical trials.[2]

When taken in dosages of 10 or 25 mg once a day, the incidence of adverse events was similar to placebo. However, there was a higher frequency of genital infections at both the 10 mg and the 25 mg dosages.

1-chloro-4-(β-D-glucopyranos-1-yl)-2-[4-((S)-tetrahydrofuran-3-yloxy)-benzyl]-benzene of the formula

Figure US20130252908A1-20130926-C00001

as described for example in WO 2005/092877. Methods of synthesis are described in the literature, for example WO 06/120208 and WO 2011/039108. According to this invention, it is to be understood that the definition of empagliflozin also comprises its hydrates, solvates and polymorphic forms thereof, and prodrugs thereof. An advantageous crystalline form of empagliflozin is described in WO 2006/117359 and WO 2011/039107 which hereby are incorporated herein in their entirety. This crystalline form possesses good solubility properties which enables a good bioavailability of the SGLT2 inhibitor. Furthermore, the crystalline form is physico-chemically stable and thus provides a good shelf-life stability of the pharmaceutical composition. Preferred pharmaceutical compositions, such as solid formulations for oral administration, for example tablets, are described in WO 2010/092126,

http://www.google.com/patents/WO2011039108A2

Example 1 : Synthesis of the fluoride VIII.1

Oxalylchloride (176kg; 1386mol; 1 ,14eq) is added to a mixture of 2-chloro-5-iodo benzoic acid (343kg; 1214mol) (compound IX.1 ), fluorobenzene (858kg) and N,N-dimethylformamide (2kg) within 3 hours at a temperature in the range from about 25 to 30°C (gas formation). After completion of the addition, the reaction mixture is stirred for additional 2 hours at a temperature of about 25 to 30°C. The solvent (291 kg) is distilled off at a temperature between 40 and 45°C (p=200mbar). Then the reaction solution (91 1 kg) is added to aluminiumchloride AICI3 (181 kg) and fluorobenzene (192kg) at a temperature between about 25 and 30°C within 2 hours. The reaction solution is stirred at the same temperature for about an additional hour. Then the reaction mixture is added to an amount of 570 kg of water within about 2 hours at a temperature between about 20 and 30°C and stirred for an additional hour. After phase separation the organic phase (1200kg) is separated into two halves (600kg each). From the first half of the organic phase solvent (172kg) is distilled off at a temperature of about 40 to 50°C (p=200mbar). Then 2-propanole (640kg) is added. The solution is heated to about 50°C and then filtered through a charcoal cartouche (clear filtration). The cartouche may be exchanged during filtration and washed with a

fluorobenzene/2-propanole mixture (1 :4; 40kg) after filtration. Solvent (721 kg) is distilled off at a temperature of about 40 to 50°C and p=200mbar. Then 2-propanole (240kg) is added at a temperature in the range between about 40 to 50°C. If the content of fluorobenzene is greater than 1 % as determined via GC, another 140kg of solvent are distilled off and 2- propanole (140kg) is added. Then the solution is cooled from about 50°C to 40°C within one hour and seeding crystals (50g) are added. The solution is further cooled from about 40°C to 20°C within 2 hours. Water (450kg) is added at about 20°C within 1 hour and the suspension is stirred at about 20°C for an additional hour before the suspension is filtered. The filter cake is washed with 2-propanole/water (1 :1 ; 800kg). The product is dried until a water level of <0.06%w/w is obtained. The second half of the organic phase is processed identically. A total of 410kg (94%yield) of product which has a white to off-white crystalline appearance, is obtained. The identity of the product is determined via infrared spectrometry.

Example 2: Synthesis of the ketone VII.1

To a solution of the fluoride VIII.1 (208kg), tetrahydrofuran (407kg) and (S)-3- hydroxytetrahydrofuran (56kg) is added potassium-ie f-butanolate solution (20%) in tetrahydrofuran (388kg) within 3 hrs at 16 to 25°C temperature. After completion of the addition, the mixture is stirred for 60min at 20°C temperature. Then the conversion is determined via HPLC analysis. Water (355kg) is added within 20 min at a temperature of 21 °C (aqueous quench). The reaction mixture is stirred for 30 min (temperature: 20°C). The stirrer is switched off and the mixture is left stand for 60 min (temperature: 20°C). The phases are separated and solvent is distilled off from the organic phase at 19 to 45°C temperature under reduced pressure. 2-Propanol (703kg) is added to the residue at 40 to 46°C temperature and solvent is distilled off at 41 to 50°C temperature under reduced pressure. 2-Propanol (162kg) is added to the residue at 47°C temperature and solvent is distilled off at 40 to 47°C temperature under reduced pressure. Then the mixture is cooled to 0°C within 1 hr 55 min. The product is collected on a centrifuge, washed with a mixture of 2- propanol (158kg) and subsequently with ie f.-butylmethylether (88kg) and dried at 19 to 43°C under reduced pressure. 227kg (91 ,8%) of product are obtained as colourless solid. The identity of the product is determined via infrared spectrometry.

Example 3: Synthesis of the iodide V.1

To a solution of ketone VII.1 (217,4kg) and aluminium chloride (AICI3; 81 ,5kg) in toluene (366,8kg) is added 1 ,1 ,3,3-tetramethyldisiloxane (TMDS, 82,5kg) within 1 hr 30 min

(temperature: 18-26°C). After completion of the addition, the mixture is stirred for additional 1 hr at a temperature of 24°C. Then the conversion is determined via HPLC analysis.

Subsequently the reaction mixture is treated with acetone (15,0kg), stirred for 1 hr 5 min at 27°C temperature and the residual TMDS content is analyzed via GC. Then a mixture of water (573kg) and concentrated HCI (34kg) is added to the reaction mixture at a temperature of 20 to 51 °C (aqueous quench). The reaction mixture is stirred for 30 min (temperature:

51 °C). The stirrer is switched off and the mixture is left stand for 20 min (temperature: 52°C). The phases are separated and solvent is distilled off from the organic phase at 53-73°C temperature under reduced pressure. Toluene (52,8kg) and ethanol (435,7kg) are added to the residue at 61 to 70°C temperature. The reaction mixture is cooled to 36°C temperature and seeding crystals (0,25kg) are added. Stirring is continued at this temperature for 35 min. Then the mixture is cooled to 0 to 5°C and stirred for additional 30 min. The product is collected on a centrifuge, washed with ethanol (157kg) and dried at 15 to 37°C under reduced pressure. 181 kg (82,6%) of product are obtained as colourless solid. The identity of the product is determined via the HPLC retention time.

Example 4: Synthesis of the lactone IV.1

A suspension of the D-(+)-gluconic acid-delta-lactone IVa.1 (42,0kg), tetrahydrofuran (277,2kg), 4-methylmorpholine (NMM; 152,4kg) and 4-dimethylaminopyridine (DMAP;

1 ,44kg) is treated with chlorotrimethylsilane (TMSCI; 130,8kg) within 50 min at 13 to 19°C. After completion of the addition stirring is continued for 1 hr 30 min at 20 to 22°C and the conversion is determined via HPLC analysis. Then n-heptane (216,4kg) is added and the mixture is cooled to 5°C. Water (143kg) is added at 3 to 5°C within 15 min. After completion of the addition the mixture is heated to 15°C and stirred for 15 min. The stirrer is switched off and the mixture is left stand for 15 min. Then the phases are separated and the organic layer is washed in succession two times with water (143kg each). Then solvent is distilled off at 38°C under reduced pressure and n-heptane (130kg) is added to the residue. The resulting solution is filtered and the filter is rinsed with n-heptane (63kg) (filter solution and product solution are combined). Then solvent is distilled off at 39 to 40°C under reduced pressure. The water content of the residue is determined via Karl-Fischer analysis (result: 0,0%).

1 12,4kg of the product is obtained as an oil (containing residual n-heptane, which explains the yield of >100%). The identity of the product is determined via infrared spectrometry.

Example 5a: Synthesis of the glucoside 11.1

To a solution of the iodide V.1 (267kg) in tetrahydrofuran (429kg) is added Turbogrignard solution (isopropylmagnesium chloride/lithium chloride solution, 14 weight-% iPrMgCI in THF, molar ratio LiCI : iPrMgCI = 0,9 – 1 .1 mol/mol) (472kg) at -21 to -15°C temperature within 1 hr 50 min. On completion of the addition the conversion is determined via HPLC analysis. The reaction is regarded as completed when the area of the peak corresponding to the iodide V.1 is smaller than 5,0% of the total area of both peaks, iodide V.1 and the corresponding desiodo compound of iodide V.1 . If the reaction is not completed, additional Turbogrignard solution is added until the criterion is met. In this particular case the result is 3,45%. Then the lactone IV.1 (320kg) is added at -25 to -18°C temperature within 1 hr 25 min. The resulting mixture is stirred for further 1 hr 30 min at -13 to -18°C. On completion the conversion is determined via HPLC analysis (for information). On completion, a solution of citric acid in water (938L; concentration: 10 %-weight) is added to the reaction mixture of a volume of about 2500L at -13 to 19°C within 1 hr 25 min.

The solvent is partially distilled off from the reaction mixture (residual volume: 1816-1905L) at 20 to 30°C under reduced pressure and 2-methyltetrahydrofuran (532kg) is added. Then the stirrer is switched off and the phases are separated at 29°C. After phase separation the pH value of the organic phase is measured with a pH electrode (Mettler Toledo MT HA 405 DPA SC) or alternatively with pH indicator paper (such as pH-Fix 0-14, Macherey and Nagel). The measured pH value is 2 to 3. Then solvent is distilled off from the organic phase at 30 to 33°C under reduced pressure and methanol (1202kg) is added followed by the addition of a solution of 1 ,25N HCI in methanol (75kg) at 20°C (pH = 0). Full conversion to the acetale 111.1 is achieved by subsequent distillation at 20 to 32°C under reduced pressure and addition of methanol (409kg).

Completion of the reaction is obtained when two criteria are fulfilled:

1 ) The ratio of the sum of the HPLC-area of the alpha-form + beta-form of intermediate 111.1 relative to the area of intermediate llla.1 is greater or equal to 96,0% : 4,0%. 2) The ratio of the HPLC-area of the alpha-form of intermediate 111.1 to the beta-form of 111.1 is greater or equal to 97,0% to 3,0%.

In this particular case both criteria are met. Triethylamin (14kg) is added (pH = 7,4) and solvent is distilled off under reduced pressure, acetonitrile (835kg) is added and further distilled under reduced pressure. This procedure is repeated (addition of acetonitrile: 694kg) and methylene chloride (640kg) is added to the resulting mixture to yield a mixture of the acetale 111.1 in acetonitrile and methylene chloride. The water content of the mixture is determined via Karl Fischer titration (result: 0,27%).

The reaction mixture is then added within 1 hr 40 min at 10 to 19°C to a preformed mixture of AICI3 (176kg), methylene chloride (474kg), acetonitrile (340kg), and triethylsilane (205kg). The resulting mixture is stirred at 18 to 20°C for 70 min. After completion of the reaction, water (1263L) is added at 20 to 30°C within 1 hr 30 min and the mixture is partially distilled at 30 to 53°C under atmospheric pressure and the phases are separated. Toluene (698kg) is added to the organic phase and solvent is distilled off under reduced pressure at 22 to 33°C. The product is then crystallized by addition of seeding crystals (0,5kg) at 31 °C and water (267kg) added after cooling to 20°C. The reaction mixture is cooled to 5°C within 55 min and stirred at 3 to 5°C for 12 hrs. Finally the product is collected on a centrifuge as colourless, crystalline solid, washed with toluene (348kg) and dried at 22 to 58°C. 21 1 kg (73%) of product are obtained. The identity of the product is determined via the HPLC retention time.

Example 5b: Synthesis of the glucoside 11.1

To a solution of the iodide V.1 (30g) in tetrahydrofuran (55ml_) is added Turbogrignard solution (isopropylmagnesium chloride/lithium chloride solution, 14 weight-% iPrMgCI in THF, molar ratio LiCI : iPrMgCI = 0,9 – 1 .1 mol/mol) (53g) at -14 to -13°C temperature within 35 min. On completion of the addition the conversion is determined via HPLC analysis. The reaction is regarded as completed when the area of the peak corresponding to the iodide V.1 is smaller than 5,0% of the total area of both peaks, iodide V.1 and the corresponding desiodo compound of iodide V.1 . If the reaction is not completed, additional Turbogrignard solution is added until the criterion is met. In this particular case the result is 0,35%. Then the lactone IV.1 (36g) is added at -15 to -6°C temperature within 15 min. The resulting mixture is stirred for further 1 hr at -6 to -7°C. On completion, the conversion is determined via HPLC analysis (for information). On completion, a solution of citric acid in water (105mL;

concentration: 10 %-weight) is added to the reaction mixture at -15 to 10°C within 30 min. The solvent is partially distilled off from the reaction mixture (residual volume: 200mL) at 20 to 35°C under reduced pressure and 2-methyltetrahydrofuran (71 mL) is added. Then the mixture is stirred for 25min at 30°C. Then the stirrer is switched off and the phases are separated at 30°C. After phase separation the pH value of the organic phase is measured with a pH electrode (Mettler Toledo MT HA 405 DPA SC) or alternatively with pH indicator paper (such as pH-Fix 0-14, Macherey and Nagel). The measured pH value is 3. Then solvent is distilled off from the organic phase at 35°C under reduced pressure and methanol (126ml_) is added followed by the addition of a solution of 1 ,25N HCI in methanol (10,1 ml_) at 25°C (pH = 1 -2). Full conversion to the acetale 111.1 is achieved by subsequent distillation at 35°C under reduced pressure and addition of methanol (47ml_).

Completion of the reaction is obtained when two criteria are fulfilled:

1 ) The ratio of the sum of the HPLC-area of the alpha-form + beta-form of intermediate 111.1 relative to the area of intermediate llla.1 is greater or equal to 96,0% : 4,0%. In this particular case the ratio is 99,6% : 0,43%.

2) The ratio of the HPLC-area of the alpha-form of intermediate 111.1 to the beta-form of III.1 is greater or equal to 97,0% to 3,0%. In this particular case the ratio is 98,7% : 1 ,3%.

Triethylamin (2,1 mL) is added (pH = 9) and solvent is distilled off at 35°C under reduced pressure, acetonitrile (120ml_) is added and further distilled under reduced pressure at 30 to 35°C. This procedure is repeated (addition of acetonitrile: 102ml_) and methylene chloride (55ml_) is added to the resulting mixture to yield a mixture of the acetale 111.1 in acetonitrile and methylene chloride. The water content of the mixture is determined via Karl Fischer titration (result: 0,04%).

The reaction mixture is then added within 1 hr 5 min at 20°C to a preformed mixture of AICI3 (19,8g), methylene chloride (49ml_), acetonitrile (51 mL), and triethylsilane (23g). The resulting mixture is stirred at 20 to 30°C for 60 min. After completion of the reaction, water (156mL) is added at 20°C within 25 min and the mixture is partially distilled at 55°C under atmospheric pressure and the phases are separated at 33°C. The mixture is heated to 43°C and toluene (90mL) is added and solvent is distilled off under reduced pressure at 41 to 43°C. Then acetonitrile (1 OmL) is added at 41 °C and the percentage of acetonitrile is determined via GC measurement. In this particular case, the acetonitrile percentage is 27%- weight. The product is then crystallized by addition of seeding crystals (0,1 g) at 44°C and the mixture is further stirred at 44°C for 15min. The mixture is then cooled to 20°C within 60min and water (142mL) is added at 20°C within 30min. The reaction mixture is cooled to 0 to 5°C within 60 min and stirred at 3°C for 16 hrs. Finally the product is collected on a filter as colourless, crystalline solid, washed with toluene (80mL) and dried at 20 to 70°C. 20, 4g (62,6%) of product are obtained. The identity of the product is determined via the HPLC retention time.

  1.  Grempler R, Thomas L, Eckhardt M, Himmelsbach F, Sauer A, Sharp DE, Bakker RA, Mark M, Klein T, Eickelmann P (January 2012). “Empagliflozin, a novel selective sodium glucose cotransporter-2 (SGLT-2) inhibitor: characterisation and comparison with other SGLT-2 inhibitors”. Diabetes Obes Metab 14 (1): 83–90. doi:10.1111/j.1463-1326.2011.01517.xPMID 21985634.
  2. “Empagliflozin”clinicaltrials.gov. U.S. National Institutes of Health. Retrieved 22 September 2012.
  3.  Nair S, Wilding JP (January 2010). “Sodium glucose cotransporter 2 inhibitors as a new treatment for diabetes mellitus”. J. Clin. Endocrinol. Metab. 95 (1): 34–42. doi:10.1210/jc.2009-0473PMID 19892839.
  4.  Bays H (March 2009). “From victim to ally: the kidney as an emerging target for the treatment of diabetes mellitus”. Curr Med Res Opin25 (3): 671–81. doi:10.1185/03007990802710422PMID 19232040.
  5.  Abdul-Ghani MA, DeFronzo RA (September 2008). “Inhibition of renal glucose reabsorption: a novel strategy for achieving glucose control in type 2 diabetes mellitus”. Endocr Pract 14 (6): 782–90. PMID 18996802.

[1]. Grempler R, Thomas L, Eckhardt M et al. Empagliflozin, a novel selective sodium glucose cotransporter-2 (SGLT-2) inhibitor: characterisation and comparison with other SGLT-2 inhibitors. Diabetes Obes Metab. 2012 Jan;14(1):83-90.
Abstract
AIMS: Empagliflozin is a selective sodium glucose cotransporter-2 (SGLT-2) inhibitor in clinical development for the treatment of type 2 diabetes mellitus. This study assessed pharmacological properties of empagliflozin in vitro and pharmacokinetic properties in vivo and compared its potency and selectivity with other SGLT-2 inhibitors. METHODS: [(14)C]-alpha-methyl glucopyranoside (AMG) uptake experiments were performed with stable cell lines over-expressing human (h) SGLT-1, 2 and 4. Two new cell lines over-expressing hSGLT-5 and hSGLT-6 were established and [(14)C]-mannose and [(14)C]-myo-inositol uptake assays developed. Binding kinetics were analysed using a radioligand binding assay with [(3)H]-labelled empagliflozin and HEK293-hSGLT-2 cell membranes. Acute in vivo assessment of pharmacokinetics was performed with normoglycaemic beagle dogs and Zucker diabetic fatty (ZDF) rats. RESULTS: Empagliflozin has an IC(50) of 3.1 nM for hSGLT-2. Its binding to SGLT-2 is competitive with glucose (half-life approximately 1 h). Compared with other SGLT-2 inhibitors, empagliflozin has a high degree of selectivity over SGLT-1, 4, 5 and 6. Species differences in SGLT-1 selectivity were identified. Empagliflozin pharmacokinetics in ZDF rats were characterised by moderate total plasma clearance (CL) and bioavailability (BA), while in beagle dogs CL was low and BA was high. CONCLUSIONS: Empagliflozin is a potent and competitive SGLT-2 inhibitor with an excellent selectivity profile and the highest selectivity window of the tested SGLT-2 inhibitors over hSGLT-1. Empagliflozin represents an innovative therapeutic approach to treat diabetes.

[2]. Thomas L, Grempler R, Eckhardt M et al. Long-term treatment with empagliflozin, a novel, potent and selective SGLT-2 inhibitor, improves glycaemic control and features of metabolic syndrome in diabetic rats. Diabetes Obes Metab. 2012 Jan;14(1):94-6.
Abstract
Empagliflozin is a potent, selective sodium glucose co-transporter-2 inhibitor that is in development for the treatment of type 2 diabetes. This series of studies was conducted to assess the in vivo pharmacological effects of single or multiple doses of empagliflozin in Zucker diabetic fatty rats. Single doses of empagliflozin resulted in dose-dependent increases in urinary glucose excretion and reductions in blood glucose levels. After multiple doses (5 weeks), fasting blood glucose levels were reduced by 26 and 39% with 1 and 3 mg/kg empagliflozin, respectively, relative to vehicle. After 5 weeks, HbA1c levels were reduced (from a baseline of 7.9%) by 0.3 and 1.1% with 1 and 3 mg/kg empagliflozin, respectively, versus an increase of 1.1% with vehicle. Hyperinsulinaemic-euglycaemic clamp indicated improved insulin sensitivity with empagliflozin after multiple doses versus vehicle. These findings support the development of empagliflozin for the treatment of type 2 diabetes.

[3]. Luippold G, Klein T, Mark M, Grempler R. Empagliflozin, a novel potent and selective SGLT-2 inhibitor, improves glycaemic control alone and in combination with insulin in streptozotocin-induced diabetic rats, a model of type 1 diabetes mellitus. Diabetes Obes Metab. 2012 Jul;14(7):601-7.
Abstract
AIM: Sodium glucose cotransporter-2 (SGLT-2) is key to reabsorption of glucose in the kidney. SGLT-2 inhibitors are in clinical development for treatment of type 2 diabetes mellitus (T2DM). The mechanism may be of value also in the treatment of type 1 diabetes mellitus (T1DM). This study investigated effects of the SGLT-2 inhibitor, empagliflozin, alone and in combination with insulin, on glucose homeostasis in an animal model of T1DM. METHODS: Sprague-Dawley rats were administered a single intraperitoneal injection of streptozotocin (STZ; 60 mg/kg). Acutely, STZ rats received two doses of insulin glargine with or without empagliflozin, and blood glucose was measured. In a subchronic study, STZ rats received empagliflozin alone, one or two insulin-releasing implants or a combination of one implant and empagliflozin over 28 days; blood glucose and HbA(1c) were measured. RESULTS: In the acute setting, empagliflozin in combination with 1.5 IU insulin induced a similar glucose-lowering effect as 6 IU insulin. Both interventions were more efficacious than monotherapy with 1.5 IU insulin. In the subchronic study, 12-h blood glucose profile on day 28 in the combination group was lower than with one implant, and similar to two implants. Plasma HbA(1c) was improved in the combination group and in animals with two implants. CONCLUSIONS: Empagliflozin reduced blood glucose levels in a T1DM animal model. Empagliflozin combined with low-dose insulin showed comparable glucose-lowering efficacy to treatment with high-dose insulin. Our data suggest that empagliflozin is an efficacious adjunctive-to-insulin therapy with the clinical potential for the treatment of T1DM.

[4]. Macha S, Rose P, Mattheus M et al. Lack of drug-drug interaction between empagliflozin, a sodium glucose cotransporter-2 inhibitor, and warfarin in healthy volunteers. Diabetes Obes Metab. 2012 Oct 24. doi: 10.1111/dom.12028. [Epub ahead of print]
Abstract
AIM: To investigate potential drug-drug interactions between empagliflozin and warfarin. MATERIALS AND METHODS: Healthy subjects (n=18) received empagliflozin 25 mg qd for 5 days (treatment A), followed by empagliflozin 25 mg qd for 7 days (days 6-12) with a single 25 mg dose of warfarin on day 6 (B), and a single 25 mg dose of warfarin alone (C), in an open-label, crossover study. Subjects received treatments in sequence AB_C or C_AB with a washout period of ≥14 days between AB and C or C and AB. RESULTS: Warfarin had no effect on empagliflozin area under concentration-time curve or maximum plasma concentration at steady-state (AUC(τ) (,ss) or C(max,ss) ): geometric mean ratios (GMRs) (90% confidence intervals [CI]) were 100.89% (96.86, 105.10) and 100.64% (89.79, 112.80), respectively. Empagliflozin had no effect on AUC from 0 hours to infinity (AUC(0) (-∞) ) or C(max) for R-warfarin or S-warfarin (GMRs [90% CI] for AUC(0) (-∞) : 98.49% [95.29, 101.80] and 95.88% [93.40, 98.43], respectively; C(max) : 97.89% [91.12, 105.15] and 98.88% [91.84, 106.47], respectively). Empagliflozin had no clinically relevant effects on warfarin’s anticoagulant activity (international normalised ratio [INR]) (GMR [95% CI] for peak INR: 0.87 [0.73, 1.04]; area under the effect-time curve from 0 to 168 hours: 0.88 [0.79, 0.98]. No drug-related adverse events were reported for empagliflozin after monotherapy or combined administration. The combination of empagliflozin and warfarin was well tolerated. CONCLUSIONS: No drug-drug interactions were observed between empagliflozin and warfarin, indicating that empagliflozin and warfarin can be co-administered without dosage adjustments of either drug.

[5]. Sarashina A, Koiwai K, Seman LJ et al. Safety, Tolerability, Pharmacokinetics and Pharmacodynamics of Single Doses of Empagliflozin, a Sodium Glucose Cotransporter-2 (SGLT-2) Inhibitor, in Healthy Japanese Subjects. Drug Metab Pharmacokinet. 2012 Nov 13. [Epub ahead of print]
Abstract
This randomized, placebo-controlled within dose groups, double-blind, single rising dose study investigated the safety, tolerability, pharmacokinetics and pharmacodynamics of 1 mg to 100 mg doses of empagliflozin in 48 healthy Japanese male subjects. Empagliflozin was rapidly absorbed, reaching peak levels in 1.25 to 2.50 hours; thereafter, plasma concentrations declined in a biphasic fashion, with mean terminal elimination half-life ranging from 7.76 to 11.7 hours. Increase in empagliflozin exposure was proportional to dose. Oral clearance was dose independent and ranged from 140 to 172 mL/min. In the 24 hours following 100 mg empagliflozin administration, the mean (%CV) amount of glucose excreted in urine was 74.3 (17.1) g. The amount and the maximum rate of glucose excreted via urine increased with dose of empagliflozin. Nine adverse events, all of mild intensity, were reported by 8 subjects (7 with empagliflozin and 1 with placebo). No hypoglycemia was reported. In conclusion, 1 mg to 100 mg doses of empagliflozin had a good safety and tolerability profile in healthy Japanese male subjects. Exposure to empagliflozin was dose-proportional. The amount and rate of urinary glucose excretion were higher with empagliflozin than with placebo, and increased with empagliflozin dose.

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WO2006117359A1

formula A

Figure imgf000002_0001

Example I

Figure imgf000014_0001

(5-bromo-2-chloro-phenyl)-(4-methoxy-phenyl)-methanone

38.3 ml oxalyl chloride and 0.8 ml of dimethylformamide are added to a mixture of

100 g of 5-bromo-2-chloro-benzoic acid in 500 ml dichloromethane. The reaction mixture is stirred for 14 h, then filtered and separated from all volatile constituents in the rotary evaporator. The residue is dissolved in 150 ml dichloromethane, the solution is cooled to -5 0C, and 46.5 g of anisole are added. Then 51.5 g of aluminum trichloride are added batchwise so that the temperature does not exceed 5 0C. The solution is stirred for another 1 h at 1 to 5 0C and then poured onto crushed ice. The organic phase is separated, and the aqueous phase is extracted another three times with dichloromethane. The combined organic phases are washed with aqueous 1 M hydrochloric acid, twice with aqueous 1 M sodium hydroxide solution and with brine. Then the organic phase is dried, the solvent is removed and the residue is recrystallised in ethanol. Yield: 86.3 g (64% of theory)

Mass spectrum (ESI+): m/z = 325/327/329 (Br+CI) [M+H]+

Example Il

Figure imgf000014_0002

4-bromo-1-chloro-2-(4-methoxy-benzyl)-benzene

A solution of 86.2 g (5-bromo-2-chloro-phenyl)-(4-methoxy-phenyl)-methanone and 101.5 ml triethylsilane in 75 ml dichloromethane and 150 ml acetonitrile is cooled to 1O0C. Then with stirring 50.8 ml of boron trifluoride etherate are added so that the temperature does not exceed 2O0C. The solution is stirred for 14 h at ambient temperature, before another 9 ml triethylsilane and 4.4 ml boron trifluoride etherate are added. The solution is stirred for a further 3 h at 45 to 5O0C and then cooled to ambient temperature. A solution of 28 g potassium hydroxide in 70 ml of water is added, and the resulting mixture is stirred for 2 h. Then the organic phase is separated off and the aqueous phase is extracted another three times with diisopropylether. The combined organic phases are washed twice with aqueous 2 M potassium hydroxide solution and once with brine and then dried over sodium sulfate. After the solvent has been removed the residue is washed in ethanol, separated again and dried at 6O0C. Yield: 50.0 g (61 % of theory)

Mass spectrum (ESI+): m/z = 310/312/314 (Br+CI) [M+H]+

Example III

Figure imgf000015_0001

4-(5-bromo-2-chloro-benzyl)-phenol

A solution of 14.8 g 4-bromo-1-chloro-2-(4-methoxy-benzyl)-benzene in 150 ml dichloromethane is cooled in an ice bath. Then 50 ml of a 1 M solution of boron tribromide in dichloromethane are added, and the solution is stirred for 2 h at ambient temperature. The solution is then cooled in an ice bath again, and saturated aqueous potassium carbonate solution is added dropwise. At ambient temperature the mixture is adjusted with aqueous 1 M hydrochloric acid to a pH of 1 , the organic phase is separated, and the aqueous phase is extracted another three times with ethyl acetate. The combined organic phases are dried over sodium sulphate, and the solvent is removed completely. Yield: 13.9 g (98% of theory) Mass spectrum (ESI ): m/z = 295/297/299 (Br+CI) [M-HV

Example IV

Figure imgf000016_0001

r4-(5-bromo-2-chloro-benzyl)-phenoxyl-tert-butyl-dimethyl-silane

A solution of 13.9 g 4-(5-bromo-2-chloro-benzyl)-phenol in 140 ml dichloromethane is cooled in an ice bath. Then 7.54 g tert-butyldimethylsilylchlorid in 20 ml dichloromethane are added followed by 9.8 ml triethylamine and 0.5 g 4- dimethylaminopyridine. The solution is stirred for 16 h at ambient temperature and then diluted with 100 ml dichloromethane. The organic phase is washed twice with aqueous 1 M hydrochloric acid and once with aqueous sodium hydrogen carbonate solution and then dried over sodium sulfate. After the solvent has been removed the residue is filtered through silica gel (cyclohexane/ethyl acetate 100:1 ). Yield: 16.8 g (87% of theory) Mass spectrum (El): m/z = 410/412/414 (Br+CI) [M]+

Example V

Figure imgf000016_0002

2.3.4.6-tetrakis-O-(trimethylsilyl)-D-glucopyranone

A solution of 20 g D-glucono-1 ,5-lactone and 98.5 ml Λ/-methylmorpholine in 200 ml of tetrahydrofuran is cooled to -5 0C. Then 85 ml trimethylsilylchloride are added dropwise so that the temperature does not exceed 5 0C. The solution is then stirred for 1 h at ambient temperature, 5 h at 35 0C and again for 14 h at ambient temperature. After the addition of 300 ml of toluene the solution is cooled in an ice bath, and 500 ml of water are added so that the temperature does not exceed 100C. The organic phase is then separated and washed in each case once with aqueous sodium dihydrogen phosphate solution, water and brine. The solvent is removed, the residue is taken up in 250 ml of toluene, and the solvent is again removed completely. Yield: 52.5 g (approx. 90% pure)

Mass spectrum (ESI+): m/z = 467 [M+H]+

Example Vl

Figure imgf000017_0001

1-chloro-4-(β-D-qlucopyranos-1-yl)-2-(4-hvdroxybenzyl)-benzene

A solution of 4.0 g [4-(5-bromo-2-chloro-benzyl)-phenoxy]-te/Tf-butyl-dimethyl-silane in 42 ml dry diethyl ether is cooled to -800C under argon. 11.6 ml of a 1.7 M solution of te/if-butyllithium in pentane are slowly added dropwise to the cooled solution, and then the solution is stirred for 30 min at -80 0C. This solution is then added dropwise through a transfer needle, which is cooled with dry ice, to a solution of 4.78 g

2,3,4,6-tetrakis-O-(trimethylsilyl)-D-glucopyranone in 38 ml diethyl ether chilled to – 80 0C. The resulting solution is stirred for 3 h at -78 0C. Then a solution of 1.1 ml methanesulphonic acid in 35 ml of methanol is added and the solution is stirred for 16 h at ambient temperature. The solution is then neutralised with solid sodium hydrogen carbonate, ethyl acetate is added and the methanol is removed together with the ether. Aqueous sodium hydrogen carbonate solution is added to the remaining solution, and the resulting mixture is extracted four times with ethyl acetate. The organic phases are dried over sodium sulphate and evaporated down. The residue is dissolved in 30 ml acetonitrile and 30 ml dichloromethane and the solution is cooled to -10 0C. After the addition of 4.4 ml triethylsilane 2.6 ml boron trifluoride etherate are added dropwise so that the temperature does not exceed -5 0C. After the addition is complete the solution is stirred for another 5 h at -5 to -10 0C and then quenched by the addition of aqueous sodium hydrogen carbonate solution. The organic phase is separated, and the aqueous phase is extracted four times with ethyl acetate. The combined organic phases are dried over sodium sulfate, the solvent is removed, and the residue is purified by chromatography on silica gel (dichoromethane/methanol 1 :0->3:1 ). The product then obtained is an approx. 6:1 mixture of β/α which can be converted into the pure β-anomer by global acetylation of the hydroxy groups with acetic anhydride and pyridine in dichloromethane and recrystallization of the product from ethanol. The product thus obtained is converted into the title compound by deacetylation in methanol with aqueous 4 M potassium hydroxide solution. Yield: 1.6 g (46% of theory)

Mass spectrum (ESI+): m/z = 398/400 (Cl) [M+H]+

Preparation of the compound A:

Figure imgf000018_0001

1-chloro-4-(β-D-qlucopyranos-1-yl)-2-r4-(<fS)-tetrahvdrofuran-3-yloxy)-benzyll- benzene

0.19 g (f?)-3-(4-methylphenylsulfonyloxy)-tetrahydrofuran are added to a mixture of 0.20 g 1-chloro-4-(β-D-glucopyranos-1-yl)-2-(4-hydroxybenzyl)-benzene and 0.29 g cesium carbonate in 2.5 ml dimethylformamide. The mixture is stirred at 75 0C for 4 h, before another 0.29 g caesium carbonate and 0.19 g (f?)-3-(4-methylphenyl- sulfonyloxy)-tetrahydrofuran are added. After an additional 14 h stirring at 75 0C the mixture is cooled to ambient temperature and brine is added. The resulting mixture is extracted with ethyl acetate, the combined organic extracts are dried over sodium sulfate, and the solvent is removed. The residue is purified by chromatography on silica gel (dichloromethane/methanol 1 :0 -> 5:1 ). Yield: 0.12 g (49% of theory) Mass spectrum (ESI+): m/z = 451/453 (Cl) [M+H] +

Mitsubishi Tanabe seeks manufacturing, marketing approval for TA-7284, Canagliflozin in Japan


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http://regulatoryaffairs.pharmaceutical-business-review.com/news/mitsubishi-tanabe-seeks-manufacturing-marketing-approval-for-ta-7284-in-japan-270513

CANAGLIFLOZIN

300px
CANAGLIFLOZIN
Canagliflozin
Canagliflozin is a highly potent and selective subtype 2 sodium-glucose transport protein (SGLT2) inhibitor to CHO- hSGLT2, CHO- rSGLT2 and CHO- mSGLT2 with IC50 of 4.4 nM, 3.7 nM and 2 nM, respectively.


M.F.C24H25FO5S
M.Wt: 444.52
CAS No: 842133-18-0
(1S)-1,5-Anhydro-1-C-[3-[[5-(4-fluorophenyl)-2-thienyl]methyl]-4-methylphenyl]-D-glucitol
1-(β-D-glucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2-thienylmethyl]benzene
NMR…..http://file.selleckchem.com/downloads/nmr/S276003-Canagliflozin-HNMR-Selleck.pdf

Canagliflozin Hemihydrate
(1S)-1,5-Anhydro-1-C-[3-[[5-(4-fluorophenyl)-2-thienyl]methyl]-4-methylphenyl]-D-glucitol hydrate (2:1)
928672-86-0

Canagliflozin (INN, trade name Invokana) is a drug of the gliflozin class, used for the treatment of type 2 diabetes.[1][2] It was developed by Mitsubishi Tanabe Pharma and is marketed under license by Janssen, a division of Johnson & Johnson.[3]
U.S. Patent No, 7,943,788 B2 (the ‘788 patent) discloses canagliflozin or salts thereof and the process for its preparation.
U.S. Patent Nos. 7,943,582 B2 and 8,513,202 B2 discloses crystalline form of 1 -(P-D-glucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2-thienylmethyl] benzene hemihydrate and process for preparation thereof. The US ‘582 B2 and US ‘202 B2 further discloses that preparation of the crystalline form of hemi-hydrate canagliflozin typically involves dissolving in a good solvent (e.g. ketones or esters) crude or amorphous compound prepared in accordance with the procedures described in WO 2005/012326 pamphlet, and adding water and a poor solvent (e.g. alkanes or ethers) to the resulting solution, followed by filtration.
U.S. PG-Pub. No. 2013/0237487 Al (the US ‘487 Al) discloses amorphous dapagliflozin and amorphous canagliflozin. The US ‘487 Al also discloses 1:1 crystalline complex of canagliflozin with L-proline (Form CS1), ethanol solvate of a 1: 1 crystalline complex of canagliflozin with D-proline (Form CS2), 1 :1 crystalline complex of canagliflozin with L-phenylalanine (Form CS3), 1:1 crystalline complex of canagliflozin with D-proline (Form CS4).
The US ‘487 Al discloses preparation of amorphous canagliflozin by adding its heated toluene solution into n-heptane. After drying in vacuo the product was obtained as a white solid of with melting point of 54.7°C to 72.0°C. However, upon repetition of the said experiment, the obtained amorphous canagliflozin was having higher amount of residual solvents. Therefore, the amorphous canagliflozin obtained by process as disclosed in US ‘487 Al is not suitable for pharmaceutical preparations.
The US ‘487 Al further discloses that amorphous canagliflozin obtained by the above process is hygroscopic in nature which was confirmed by Dynamic vapor sorption (DVS) analysis. Further, it was observed that the amorphous form underwent a physical change between the sorption/desorption cycle, making the sorption/desorption behavior different between the two cycles. The physical change that occurred was determined to be a conversion or partial conversion from the amorphous state to a crystalline state. This change was supported by a change in the overall appearance of the sample as the humidity increased from 70% to 90% RH.
The canagliflozin assessment report EMA/718531/2013 published by EMEA discloses that Canagliflozin hemihydrate is a white to off-white powder^ practically insoluble in water and freely soluble in ethanol and non-hygroscopic. Polymorphism has been observed for canagliflozin and the manufactured Form I is a hemihydrate, and an unstable amorphous Form II. Form I is consistently produced by the proposed commercial synthesis process. Therefore, it is evident from the prior art that the reported amorphous form of canagliflozin is unstable and hygroscopic as well as not suitable for pharmaceutical preparations due to higher amount of residual solvents above the ICH acceptable limits.
Medical use

    1. Canagliflozin is an antidiabetic drug used to improve glycemic control in people with type 2 diabetes. In extensive clinical trials, canagliflozin produced a consistent dose-dependent reduction in HbA1c of 0.77% to 1.16% when administered as monotherapy, combination with metformin, combination with metformin & Sulfonyulrea, combination with metformin & pioglitazone and In combination with insulin from a baselines of 7.8% to 8.1%, in combination with metformin, or in combination with metformin and a sulfonylurea. When added to metformin Canagliflozin 100mg was shown to be non-inferior to both Sitagliptin 100mg and glimiperide in reductions on HbA1c at one year, whilst canagliflozin 300mg successfully demontrated statistical superiority over both Sitagliptin and glimiperide in HbA1c reductions. Secondary efficacy endpoint of superior body weight reduction and blood pressure reduction (versus Sitagliptin and glimiperide)) were observed as well. Canagliflozin produces beneficial effects on HDL cholesterol whilst increasing LDL cholesterol to produce no change in total cholesterol.[4][5]

      Contraindications

      Canagliflozin has proven to be clinically effective in people with moderate renal failure and treatment can be continued in patients with renal impairment.

      Adverse effects

      Canagliflozin, as is common with all sglt2 inhibitors, increased (generally mild) urinary tract infections, genital fungal infections, thirst,[6] LDL cholesterol, and was associated with increased urination and episodes of low blood pressure.
      There are concerns it may increase the risk of diabetic ketoacidosis.[7]
      Cardiovascular problems have been discussed with this class of drugs.[citation needed] The pre-specified endpoint for cardiovascular safety in the canagliflozin clinical development program was Major Cardiovascular Events Plus (MACE-Plus), defined as the occurrence of any of the following events: cardiovascular death, non-fatal myocardial infarction, non-fatal stroke, or unstable angina leading to hospitalization. This endpoint occurred in more people in the placebo group (20.5%) than in the canagliflozin treated group (18.9%).
      Nonetheless, an FDA advisory committee expressed concern regarding the cardiovascular safety of canagliflozin. A greater number of cardiovascular events was observed during the first 30 days of treatment in canagliflozin treated people (0.45%) relative to placebo treated people (0.07%), suggesting an early period of enhanced cardiovascular risk. In addition, there was an increased risk of stroke in canagliflozin treated people. However none of these effects were seen as statistically significant. Additional cardiovascular safety data from the ongoing CANVAS trial is expected in 2015.[8]

      Interactions

      The drug may increase the risk of dehydration in combination with diuretic drugs.
      Because it increases renal excretion of glucose, treatment with canagliflozin prevents renal reabsorption of 1,5-anhydroglucitol, leading to artifactual decreases in serum 1,5-anhydroglucitol; it can therefore interfere with the use of serum 1,5-anhydroglucitol (assay trade name, GlycoMark) as a measure of postprandial glucose excursions.[9]

      Mechanism of action

      Canagliflozin is an inhibitor of subtype 2 sodium-glucose transport protein (SGLT2), which is responsible for at least 90% of the renal glucose reabsorption (SGLT1 being responsible for the remaining 10%). Blocking this transporter causes up to 119 grams of blood glucose per day to be eliminated through the urine,[10] corresponding to 476 kilocalories. Additional water is eliminated by osmotic diuresis, resulting in a lowering of blood pressure.
      This mechanism is associated with a low risk of hypoglycaemia (too low blood glucose) compared to other antidiabetic drugs such as sulfonylurea derivatives and insulin.[11]

      History

      On July 4, 2011, the European Medicines Agency approved a paediatric investigation plan and granted both a deferral and a waiver for canagliflozin (EMEA-001030-PIP01-10) in accordance with EC Regulation No.1901/2006 of the European Parliament and of the Council.[12]
      In March 2013, canagliflozin became the first SGLT2 inhibitor to be approved in the United States.[13]
      SYNTHESIS

…………
CANA1CANA2

………….

Canagliflozin is an API that is an inhibitor of SGLT2 and is being developed for the treatment of type 2 diabetes mellitus.[0011] The IUPAC systematic name of canagliflozin is (25,,3/?,4i?,55′,6 ?)-2-{3-[5-[4-fluoro- phenyl)-thiophen-2-ylmethyl]-4-methyl-phenyl}-6-hydroxymethyl-tetrahydro-pyran-3,4,5-triol, and is also known as (15)-l,5-anhydro-l-C-[3-[[5-(4-fluorophenyl)-2-thienyl]methyl]-4- methylphenyl]-D-glucitol and l-( -D-glucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2- thienylmethyl]benzene. Canagliflozin is a white to off-white powder with a molecular formula of C24H25F05S and a molecular weight of 444.52. The structure of canagliflozin is shown as compound B.

Compound B – Canagliflozin
[0012] In US 2008/0146515 Al, a crystalline hemihydrate form of canagliflozin (shown as Compound C) is disclosed, having the powder X-ray diffraction (XRPD) pattern comprising the following 2Θ values measured using CuKa radiation: 4.36±0.2, 13.54±0.2, 16.00±0.2, 19.32±0.2, and 20.80±0.2. The XRPD pattern is shown in Figure 24. A process for the preparation of canagliflozin hemihydrate is also disclosed in US 2008/0146515 Al.

Compound C – hemihydrate form of canagliflozin
[0013] In US 2009/0233874 Al, a crystalline form of canagliflozin is disclosed.

……..

WO 2005/012326 pamphlet discloses a class of compounds that are inhibitors of sodium-dependent glucose transporter (SGLT) and thus of therapeutic use for treatment of diabetes, obesity, diabetic complications, and the like. There is described in WO 2005/012326 pamphlet 1-(β-D-glucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2-thienylmethyl]benzene of formula (I):

Example 1 Crystalline 1-(β-D-glucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2-thienylmethyl]benzene hemihydrate1-(β-D-glucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2-thienylmethyl]benzene was prepared in a similar manner as described in WO 2005/012326.

(1) To a solution of 5-bromo-1-[5-(4-fluorophenyl)-2-thienylmethyl]-2-methylbenzene (1, 28.9 g) in tetrahydrofuran (480 ml) and toluene (480 ml) was added n-butyllithium (1.6M hexane solution, 50.0 ml) dropwise at −67 to −70° C. under argon atmosphere, and the mixture was stirred for 20 minutes at the same temperature. Thereto was added a solution of 2 (34.0 g) in toluene (240 ml) dropwise at the same temperature, and the mixture was further stirred for 1 hour at the same temperature. Subsequently, thereto was added a solution of methanesulfonic acid (21.0 g) in methanol (480 ml) dropwise, and the resulting mixture was allowed to warm to room temperature and stirred for 17 hours. The mixture was cooled under ice—water cooling, and thereto was added a saturated aqueous sodium hydrogen carbonate solution. The mixture was extracted with ethyl acetate, and the combined organic layer was washed with brine and dried over magnesium sulfate. The insoluble was filtered off and the solvent was evaporated under reduced pressure. The residue was triturated with toluene (100 ml)—hexane (400 ml) to give 1-(1-methoxyglucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2-thienylmethyl]-benzene (3) (31.6 g). APCI-Mass m/Z 492 (M+NH4).
(2) A solution of 3 (63.1 g) and triethylsilane (46.4 g) in dichloromethane (660 ml) was cooled by dry ice-acetone bath under argon atmosphere, and thereto was added dropwise boron trifluoride•ethyl ether complex (50.0 ml), and the mixture was stirred at the same temperature. The mixture was allowed to warm to 0° C. and stirred for 2 hours. At the same temperature, a saturated aqueous sodium hydrogen carbonate solution (800 ml) was added, and the mixture was stirred for 30 minutes. The organic solvent was evaporated under reduced pressure, and the residue was poured into water and extracted with ethyl acetate twice. The organic layer was washed with water twice, dried over magnesium sulfate and treated with activated carbon. The insoluble was filtered off and the solvent was evaporated under reduced pressure. The residue was dissolved in ethyl acetate (300 ml), and thereto were added diethyl ether (600 ml) and H2O (6 ml). The mixture was stirred at room temperature overnight, and the precipitate was collected, washed with ethyl acetate-diethyl ether (1:4) and dried under reduced pressure at room temperature to give 1-(β-D-glucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2-thienylmethyl]benzene hemihydrate (33.5 g) as colorless crystals.
mp 98-100° C. APCI-Mass m/Z 462 (M+NH4). 1H-NMR (DMSO-d6) δ 2.26 (3H, s), 3.13-3.28 (4H, m), 3.44 (1H, m), 3.69 (1H, m), 3.96 (1H, d, J=9.3 Hz), 4.10, 4.15 (each 1H, d, J=16.0 Hz), 4.43 (1H, t, J=5.8 Hz), 4.72 (1H, d, J=5.6 Hz), 4.92 (2H, d, J=4.8 Hz), 6.80 (1H, d, J=3.5 Hz), 7.11-7.15 (2H, m), 7.18-7.25 (3H, m), 7.28 (1H, d, J=3.5 Hz), 7.59 (2H, dd, J=8.8, 5.4 Hz).
Anal. Calcd. for C24H25FO5S.0.5H2O: C, 63.56; H, 5.78; F, 4.19; S, 7.07. Found: C, 63.52; H, 5.72; F, 4.08; S, 7.00.
1-(β-D-glucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2-thienylmethyl]benzene
Figure US07943582-20110517-C00001

Example 2An amorphous powder of 1-(β-D-glucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2-thienylmethyl]benzene (1.62 g) was dissolved in acetone (15 ml), and thereto were added H2O (30 ml) and a crystalline seed. The mixture was stirred at room temperature for 18 hours, and the precipitate was collected, washed with acetone—H2O (1:4, 30 ml) and dried under reduced pressure at room temperature to give 1-(β-D-glucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2-thienylmethyl]benzene hemihydrate (1.52 g) as colorless crystals. mp 97-100° C.

……..

there are a significant number of other β-C-arylglucoside derived drug candidates, most of which differ only in the aglycone moiety (i.e., these compounds comprise a central 1-deoxy-glucose ring moiety that is arylated at CI). It is this fact that makes them attractive targets for a novel synthetic platform technology, since a single methodology should be able to furnish a plurality of products. Among β-C-arylglucosides that possess known SGLT2 inhibition also currently in clinical development are canagliflozin, empagliflozin, and ipragliflozin.

Dapagliflozin                             Canagliflozin

Ipragliflozin …………………Empagliflozin
[0007] A series of synthetic methods have been reported in the peer-reviewed and patent literature that can be used for the preparation of β-C-arylglucosides. These methods are described below and are referred herein as the gluconolactone method, the metalated glucal method, the glucal epoxide method and the glycosyl leaving group substitution method.
[0008] The gluconolactone method: In 1988 and 1989 a general method was reported to prepare C-arylglucosides from tetra-6>-benzyl protected gluconolactone, which is an oxidized derivative of glucose (see J. Org. Chem. 1988, 53, 752-753 and J. Org. Chem. 1989, 54, 610- 612). The method comprises: 1) addition of an aryllithium derivative to the hydroxy-protected gluconolactone to form a hemiketal (a.k.ci., a lactol), and 2) reduction of the resultant hemiketal with triethylsilane in the presence of boron trifluoride etherate. Disadvantages of this classical, but very commonly applied method for β-C-arylglucoside synthesis include:
1) poor “redox economy” (see J. Am. Chem. Soc. 2008, 130, 17938-17954 and Anderson, N. G. Practical Process Research & Development, 1st Ed.; Academic Press, 2000 (ISBN- 10: 0120594757); pg 38)— that is, the oxidation state of the carbon atom at CI, with respect to glucose, is oxidized in the gluconolactone and then following the arylation step is reduced to provide the requisite oxidation state of the final product. 2) due to a lack of stereospecificity, the desired β-C-arylglucoside is formed along with the undesired a-C-arylglucoside stereoisomer (this has been partially addressed by the use of hindered trialkylsilane reducing agents (see Tetrahedron: Asymmetry 2003, 14, 3243-3247) or by conversion of the hemiketal to a methyl ketal prior to reduction (see J. Org. Chem. 2007, 72, 9746-9749 and U.S. Patent 7,375,213)).
Oxidation Reduction

Glucose Gluconoloctone Hemiketal a-anomer β-anomer
R = protecting group
[0009] The metalated glucal method: U.S. Patent 7,847,074 discloses preparation of SGLT2 inhibitors that involves the coupling of a hydroxy-protected glucal that is metalated at CI with an aryl halide in the presence of a transition metal catalyst. Following the coupling step, the requisite formal addition of water to the C-arylglucal double bond to provide the desired C-aryl glucoside is effected using i) hydroboration and oxidation, or ii) epoxidation and reduction, or iii) dihydroxylation and reduction. In each case, the metalated glucal method represents poor redox economy because oxidation and reduction reactions must be conducted to establish the requisite oxidation states of the individual CI and C2 carbon atoms.
[0010] U.S. Pat. Appl. 2005/0233988 discloses the utilization of a Suzuki reaction between a CI -boronic acid or boronic ester substituted hydroxy-protected glucal and an aryl halide in the presence of a palladium catalyst. The resulting 1- C-arylglucal is then formally hydrated to provide the desired 1- C-aryl glucoside skeleton by use of a reduction step followed by an oxidation step. The synthesis of the boronic acid and its subsequent Suzuki reaction, reduction and oxidation, together, comprise a relatively long synthetic approach to C-arylglucosides and exhibits poor redox economy. Moreover, the coupling catalyst comprises palladium which is toxic and therefore should be controlled to very low levels in the drug substance.

R = protecting group; R’ = H or alkyl
[0011] The glucal epoxide method: U.S. Patent 7,847,074 discloses a method that utilizes an organometallic (derived from the requisite aglycone moiety) addition to an electrophilic epoxide located at C1-C2 of a hydroxy-protected glucose ring to furnish intermediates useful for SGLT2 inhibitor synthesis. The epoxide intermediate is prepared by the oxidation of a hydroxy- protected glucal and is not particularly stable. In Tetrahedron 2002, 58, 1997-2009 it was taught that organometallic additions to a tri-6>-benzyl protected glucal-derived epoxide can provide either the a-C-arylglucoside, mixtures of the a- and β-C-arylglucoside or the β-C-arylglucoside by selection of the appropriate counterion of the carbanionic aryl nucleophile (i.e., the
organometallic reagent). For example, carbanionic aryl groups countered with copper (i.e., cuprate reagents) or zinc (i.e., organozinc reagents) ions provide the β-C-arylglucoside, magnesium ions provide the a- and β-C-arylglucosides, and aluminum (i.e., organoaluminum reagents) ions provide the a-C-arylglucoside.

or Zn[0012] The glycosyl leaving group substitution method: U.S. Patent 7,847,074, also disclosed a method comprising the substitution of a leaving group located at CI of a hydroxy-protected glucosyl species, such as a glycosyl halide, with a metalated aryl compound to prepare SGLT2 inhibitors. U.S. Pat. Appl. 2011/0087017 disclosed a similar method to prepare the SGLT2 inhibitor canagliflozin and preferably diarylzinc complexes are used as nucleophiles along with tetra- >-pivaloyl protected glucosylbromide.

Glucose Glucosyl bromide β-anomer
[0013] Methodology for alkynylation of 1,6-anhydroglycosides reported in Helv. Chim. Acta. 1995, 78, 242-264 describes the preparation of l,4-dideoxy-l,4-diethynyl^-D-glucopyranoses (a. La., glucopyranosyl acetylenes), that are useful for preparing but-l,3-diyne-l,4-diyl linked polysaccharides, by the ethynylating opening (alkynylation) of partially protected 4-deoxy-4-C- ethynyl-l,6-anhydroglucopyranoses. The synthesis of β-C-arylglucosides, such as could be useful as precursors for SLGT2 inhibitors, was not disclosed. The ethynylation reaction was reported to proceed with retention of configuration at the anomeric center and was rationalized (see Helv. Chim. Acta 2002, 85, 2235-2257) by the C3-hydroxyl of the 1,6- anhydroglucopyranose being deprotonated to form a C3-0-aluminium species, that coordinated with the C6-oxygen allowing delivery of the ethyne group to the β-face of the an oxycarbenium cation derivative of the glucopyranose. Three molar equivalents of the ethynylaluminium reagent was used per 1 molar equivalent of the 1,6-anhydroglucopyranose. The
ethynylaluminium reagent was prepared by the reaction of equimolar (i.e., 1:1) amounts of aluminum chloride and an ethynyllithium reagent that itself was formed by the reaction of an acetylene compound with butyllithium. This retentive ethynylating opening method was also applied (see Helv. Chim. Acta. 1998, 81, 2157-2189) to 2,4-di-<9-triethylsilyl- 1,6- anhydroglucopyranose to provide l-deoxy-l-C-ethynyl- -D-glucopyranose. In this example, 4 molar equivalents of the ethynylaluminium reagent was used per 1 molar equivalent of the 1,6- anhydroglucopyranose. The ethynylaluminium regent was prepared by the reaction of equimolar (i.e., 1: 1) amounts of aluminum chloride and an ethynyl lithium reagent that itself was formed by reaction of an acetylene compound with butyllithium.
[0014] It can be seen from the peer-reviewed and patent literature that the conventional methods that can be used to provide C-arylglucosides possess several disadvantages. These include (1) a lack of stereoselectivity during formation of the desired anomer of the C- arylglucoside, (2) poor redox economy due to oxidation and reduction reaction steps being required to change the oxidation state of CI or of CI and C2 of the carbohydrate moiety, (3) some relatively long synthetic routes, (4) the use of toxic metals such as palladium, and/or (5) atom uneconomic protection of four free hydroxyl groups. With regard to the issue of redox economy, superfluous oxidation and reduction reactions that are inherently required to allow introduction of the aryl group into the carbohydrate moiety of the previously mention synthetic methods and the subsequent synthetic steps to establish the required oxidation state, besides adding synthetic steps to the process, are particular undesirable for manufacturing processes because reductants can be difficult and dangerous to operate on large scales due to their flammability or ability to produce flammable hydrogen gas during the reaction or during workup, and because oxidants are often corrosive and require specialized handling operations (see Anderson, N. G. Practical Process Research & Development, 1st Ed.; Academic Press, 2000 (ISBN-10: 0120594757); pg 38 for discussions on this issue).
[0015] In view of the above, there remains a need for a shorter, more efficient and
stereoselective, redox economic process for the preparation of β-C-arylglucosides. A new process should be applicable to the industrial manufacture of SGLT2 inhibitors and their prodrugs,
EXAMPLE 22 – Synthesis of 2,4-di-0-feri-butyldiphenylsUyl-l-C-(3-((5-(4- fluorophenyl)thiophen-2-yl)methyl)-4-methylphenyl)- -D-glucopyranoside (2,4-di-6>-TBDPS- canagliflozin; (IVi”))

[0227] 2-(5-Bromo-2-methylbenzyl)-5-(4-fluorophenyl)thiophene (1.5 g, 4.15 mmol) and magnesium powder (0.33 g, 13.7 mmol) were placed in a suitable reactor, followed by THF (9 mL) and 1,2-dibromoethane (95 μί). The mixture was heated to reflux. After the reaction was initiated, a solution of 2-(5-bromo-2-methylbenzyl)-5-(4-fluorophenyl)thiophene (2.5 g, 6.92 mmol) in THF (15mL) was added dropwise. The mixture was stirred for another 2 hours under reflux, and was then cooled to ambient temperature and titrated to determine the concentration. The thus prepared 3-[[5-(4-fluorophenyl)-2-thienyl]methyl]-4-methylphenyl magnesium bromide (0.29 M in THF, 17 mL, 5.0 mmol) and A1C13 (0.5 M in THF, 4.0 mL, 2.0 mmol) were mixed at ambient temperature to give a black solution, which was stirred at ambient temperature for 1 hour. To a solution of l ,6-anhydro-2,4-di-6>-ieri-butyldiphenylsilyl- -D-glucopyranose (0.64 g, 1.0 mmol) in PhOMe (3.0 mL) at ambient temperature was added rc-BuLi (0.4 mL, 1.0 mmol, 2.5 M solution in Bu20). After stirring for about 5 min the solution was then added into the above prepared aluminum mixture via syringe, followed by additional PhOMe (1.0 mL) to rinse the flask. The mixture was concentrated under reduced pressure (50 torr) at 60 °C (external bath temperature) to remove low-boiling point ethereal solvents, and PhOMe (6 mL) was then added. The remaining mixture was heated at 150 °C (external bath temperature) for 5 hours at which time HPLC assay analysis indicated a 68% yield of 2,4-di-6>-ieri-butyldiphenylsilyl-l-C-(3-((5- (4-fluorophenyl)thiophen-2-yl)methyl)-4-methylphenyl)- -D-glucopyranoside. After cooling to ambient temperature, the reaction was treated with 10% aqueous NaOH (1 mL), THF (10 mL) and diatomaceous earth at ambient temperature, then the mixture was filtered and the filter cake was washed with THF. The combined filtrates were concentrated and the crude product was purified by silica gel column chromatography (eluting with 1 :20 MTBE/rc-heptane) to give the product 2,4-di-6>-ieri-butyldiphenylsilyl-l-C-(3-((5-(4-fluorophenyl)thiophen-2-yl)methyl)-4- methylphenyl)- -D-glucopyranoside (0.51 g, 56%) as a white powder.
1H NMR (400 MHz, CDC13) δ 7.65 (d, J= 7.2 Hz, 2H), 7.55 (d, J= 7.2 Hz, 2H), 7.48 (dd, J= 7.6, 5.6 Hz, 2H), 7.44-7.20 (m, 16H), 7.11-6.95 (m, 6H), 6.57 (d, J= 3.2 Hz, IH), 4.25 (d, J= 9.6 Hz, IH), 4.06 (s, 2H), 3.90-3.86 (m, IH), 3.81-3.76 (m, IH), 3.61-3.57 (m, IH), 3.54-3.49 (m, 2H), 3.40 (dd, J= 8.8, 8.8 Hz, IH), 2.31 (s, 3H), 1.81 (dd, J= 6.6, 6.6 Hz, IH, OH), 1.19 (d, J= 4.4 Hz, IH, OH), 1.00 (s, 9H), 0.64 (s, 9H); 13C NMR (100 MHz, CDC13) δ 162.1 (d, J= 246 Hz, C), 143.1 (C), 141.4 (C), 137.9 (C), 136.8 (C), 136.5 (C), 136.4 (CH x2), 136.1 (CH x2), 135.25 (C), 135.20 (CH x2), 135.0 (CH x2), 134.8 (C), 132.8 (C), 132.3 (C), 130.9 (d, J= 3.5 Hz, C), 130.5 (CH), 130.0 (CH), 129.7 (CH), 129.5 (CH), 129.4 (CH), 129.2 (CH), 127.6 (CH x4), 127.5 (CH x2), 127.2 (CH x2), 127.1 (d, J= 8.2 Hz, CH x2), 127.06 (CH), 126.0 (CH), 122.7 (CH), 115.7 (d, J= 21.8 Hz, CH x2), 82.7 (CH), 80.5 (CH), 79.4 (CH), 76.3 (CH), 72.9 (CH), 62.8 (CH2), 34.1(CH2), 27.2 (CH3 x3), 26.7 (CH3 x3), 19.6, (C), 19.3 (CH3),19.2 (C); LCMS (ESI) m/z 938 (100, [M+NH4]+), 943 (10, [M+Na]+).
EXAMPLE 23 – Synthesis of canagliflozin (l-C-(3-((5-(4-fluorophenyl)thiophen-2-yl)methyl)- 4-methylphenyl)- -D-glucopyranoside; (Ii))

[0228] A mixture of the 2,4-di-6>-ieri-butyldiphenylsilyl-l-C-(3-((5-(4-fluorophenyl)thiophen- 2-yl)methyl)-4-methylphenyl)- -D-glucopyranoside (408 mg, 0.44 mmol) and TBAF (3.5 mL, 3.5 mmol, 1.0 M in THF) was stirred at ambient temperature for 4 hours. CaC03 (0.73 g), Dowex 50WX8-400 ion exchange resin (2.2 g) and MeOH (5mL) were added to the product mixture and the suspension was stirred at ambient temperature for 1 hour and then the mixture was filtered through a pad of diatomaceous earth. The filter cake was rinsed with MeOH and the combined filtrates was evaporated under vacuum and the resulting residue was purified by column chromatography (eluting with 1 :20 MeOH/DCM) affording canagliflozin (143 mg, 73%).

1H NMR (400 MHz, DMSO-J6) δ 7.63-7.57 (m, 2H), 7.28 (d, J= 3.6 Hz, 1H), 7.23-7.18 (m, 3H), 7.17-7.12 (m, 2H), 6.80 (d, J= 3.6 Hz, 1H), 4.93 (br, 2H, OH), 4.73 (br, 1H, OH), 4.44 (br,IH, OH), 4.16 (d, J= 16 Hz, 1H), 4.10 (d, J= 16 Hz, 1H), 3.97 (d, J= 9.2 Hz, 1H), 3.71 (d, J=I I.6 Hz, 1H), 3.47-3.43 (m, 1H), 3.30-3.15 (m, 4H), 2.27 (s, 3H);

13C NMR (100 MHz, DMSO- d6) δ 161.8 (d, J= 243 Hz, C), 144.1 (C), 140.7 (C), 138.7 (C), 137.8 (C), 135.4 (C), 131.0 (d, J= 3.1 Hz, C), 130.1 (CH), 129.5 (CH), 127.4 (d, J= 8.1 Hz, CH x2), 126.8 (CH), 126.7 (CH), 123.9 (CH), 116.4 (d, J= 21.6 Hz, CH x2), 81.8 (CH), 81.7 (CH), 79.0 (CH), 75.2 (CH), 70.9 (CH), 61.9 (CH2), 33.9 (CH2), 19.3 (CH3);

LCMS (ESI) m/z 462 (100, [M+NH4]+), 467 (3, [M+Na]+).

Example 1 – Synthesis of l,6-anhydro-2,4-di-6>-ieri-butyldiphenylsilyl- -D-glucopyranose (II”)

III II”
[0206] To a suspension solution of l,6-anhydro- -D-glucopyranose (1.83 g, 11.3 mmol) and imidazole (3.07 g, 45.2 mmol) in THF (10 mL) at 0 °C was added dropwise a solution of TBDPSC1 (11.6 mL, 45.2 mmol) in THF (10 mL). After the l,6-anhydro-P-D-gJucopyranose was consumed, water (10 mL) was added and the mixture was extracted twice with EtOAc (20 mL each), washed with brine (10 mL), dried (Na2S04) and concentrated. Column
chromatography (eluting with 1 :20 EtOAc/rc-heptane) afforded 2,4-di-6>-ieri-butyldiphenylsilyl- l,6-anhydro- “D-glucopyranose (5.89 g, 81%).
1H NMR (400 MHz, CDC13) δ 7.82-7.70 (m, 8H), 7.49-7.36 (m, 12H), 5.17 (s, IH), 4.22 (d, J= 4.8 Hz, IH), 3.88-3.85 (m, IH), 3.583-3.579 (m, IH), 3.492-3.486 (m, IH), 3.47-3.45 (m, IH), 3.30 (dd, J= 7.4, 5.4 Hz, IH), 1.71 (d, J= 6.0 Hz, IH), 1.142 (s, 9H), 1.139 (s, 9H); 13C NMR (100 MHz, CDCI3) δ 135.89 (CH x2), 135.87 (CH x2), 135.85 (CH x2), 135.83 (CH x2), 133.8 (C), 133.5 (C), 133.3 (C), 133.2 (C), 129.94 (CH), 129.92 (CH), 129.90 (CH), 129.88 (CH), 127.84 (CH2 x2), 127.82 (CH2 x2), 127.77 (CH2 x4), 102.4 (CH), 76.9 (CH), 75.3 (CH), 73.9 (CH), 73.5 (CH), 65.4 (CH2), 27.0 (CH3 x6), 19.3 (C x2).

……..
FIG. 1:
X-ray powder diffraction pattern of the crystalline of hemihydrate of the compound of formula (I).
FIG. 2:
Infra-red spectrum of the crystalline of hemihydrate of the compound of formula (I).http://www.google.com/patents/US7943582
………….
FIGS. 3 and 4 provide the XRPD pattern and IR spectrum, respectively, of amorphous canagliflozin.
………………
Canagliflozin
300px
Systematic (IUPAC) name
(2S,3R,4R,5S,6R)-2-{3-[5-[4-Fluoro-phenyl)-thiophen-2-ylmethyl]-4-methyl-phenyl}-6-hydroxymethyl-tetrahydro-pyran-3,4,5-triol
Clinical data
Trade names Invokana
AHFS/Drugs.com entry
Pregnancy
category
  • US:C (Risk not ruled out)
Legal status
Routes of
administration
Oral
Pharmacokinetic data
Bioavailability 65%
Protein binding 99%
Metabolism Hepaticglucuronidation
Biological half-life 11.8 (10–13) hours
Excretion Fecal and 33% renal
Identifiers
CAS Registry Number 842133-18-0 Yes
ATC code A10BX11
PubChem CID: 24812758
IUPHAR/BPS 4582
DrugBank DB08907 Yes
ChemSpider 26333259 
UNII 6S49DGR869 
ChEBI CHEBI:73274 
ChEMBL CHEMBL2103841 
Synonyms JNJ-28431754; TA-7284; (1S)-1,5-anhydro-1-C-[3-[[5-(4-fluorophenyl)-2-thienyl]methyl]-4-methylphenyl]-D-glucitol
Chemical data
Formula C24H25FO5S
Molecular mass 444.52 g/mol

References

  1. “U.S. FDA approves Johnson & Johnson diabetes drug, canagliflozin”. Reuters. Mar 29, 2013. U.S. health regulators have approved a new diabetes drug from Johnson & Johnson, making it the first in its class to be approved in the United States.
WO2005012326A1 Jul 30, 2004 Feb 10, 2005 Tanabe Seiyaku Co Novel compounds having inhibitory activity against sodium-dependant transporter
WO2013064909A2 * Oct 30, 2012 May 10, 2013 Scinopharm Taiwan, Ltd. Crystalline and non-crystalline forms of sglt2 inhibitors
CN103655539A * Dec 13, 2013 Mar 26, 2014 重庆医药工业研究院有限责任公司 Oral solid preparation of canagliflozin and preparation method thereof
US7943582 Dec 3, 2007 May 17, 2011 Mitsubishi Tanabe Pharma Corporation Crystalline form of 1-(β-D-glucopyransoyl)-4-methyl-3-[5-(4-fluorophenyl)-2- thienylmethyl]benzene hemihydrate
US7943788 Jan 31, 2005 May 17, 2011 Mitsubishi Tanabe Pharma Corporation Glucopyranoside compound
US8513202 May 9, 2011 Aug 20, 2013 Mitsubishi Tanabe Pharma Corporation Crystalline form of 1-(β-D-glucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2-thienylmethyl]benzene hemihydrate
US20130237487 Oct 30, 2012 Sep 12, 2013 Scinopharm Taiwan, Ltd. Crystalline and non-crystalline forms of sglt2 inhibitors
WO2008002824A1 * Jun 21, 2007 Jan 3, 2008 Squibb Bristol Myers Co Crystalline solvates and complexes of (is) -1, 5-anhydro-l-c- (3- ( (phenyl) methyl) phenyl) -d-glucitol derivatives with amino acids as sglt2 inhibitors for the treatment of diabetes
US6774112 * Apr 8, 2002 Aug 10, 2004 Bristol-Myers Squibb Company Amino acid complexes of C-aryl glucosides for treatment of diabetes and method
US20090143316 * Apr 4, 2007 Jun 4, 2009 Astellas Pharma Inc. Cocrystal of c-glycoside derivative and l-proline
US20110087017 * Oct 14, 2010 Apr 14, 2011 Vittorio Farina Process for the preparation of compounds useful as inhibitors of sglt2
US20110098240 * Aug 15, 2008 Apr 28, 2011 Boehringer Ingelheim International Gmbh Pharmaceutical composition comprising a sglt2 inhibitor in combination with a dpp-iv inhibitor
Reference
1 * OGURA H. ET AL.: ‘5-FLUOROURACIL NUCLEOSIDES. SYNTHESIS OF A STEREO-CONTROLLED NUCLEOSIDE SYNTHESIS FROM ANHYDRO SUGARS‘ NUCLEIC ACID CHEM. vol. 4, 1991, pages 109 – 112, XP000607288
Citing Patent Filing date Publication date Applicant Title
WO2014195966A2 * May 30, 2014 Dec 11, 2014 Cadila Healthcare Limited Amorphous form of canagliflozin and process for preparing thereof
US9006188 May 23, 2014 Apr 14, 2015 Mapi Pharma Ltd. Co-crystals of dapagliflozin

///////////

1H NMR PREDICT

  13C NMR PREDICT

  COSY PREDICT

Figure

CAS 1672658-93-3
C24 H25 F O6 S, 460.52
D-Glucopyranose, 1-C-[3-[[5-(4-fluorophenyl)-2-thienyl]methyl]-4-methylphenyl]-
str1
str1
CAS 1809403-04-0
C24 H25 F O6 S, 460.52
D-Glucose, 1-C-[3-[[5-(4-fluorophenyl)-2-thienyl]methyl]-4-methylphenyl]-
WO2017/93949

Figure

(2R,3S,4R,5R)-1-(3-((5-(4-Fluorophenyl)thiophen-2-yl)methyl)-4-methylphenyl)-2,3,4,5,6-pentahydroxyhexan-1-one    12

From the FT-IR spectra of 12 contain a signal at 1674 cm–1, this signal is strongly indicative of a carbonyl ketone being present in 12

In 13C NMR and HMBC correlations spectra, the chemical shift at 199.75 ppm was observed. Analysis of the NMR data  confirmed that the structure of 12 is a ring-opened keto form

Synthesis of (2R,3S,4R,5R)-1-(3-((5-(4-Fluorophenyl)thiophen-2-yl)methyl)-4-methylphenyl)-2,3,4,5,6-pentahydroxyhexan-1-one 12

title compound 12 (84.23% yield) and having 99.4% purity by HPLC;
DSC: 160.84–166.44 °C;
Mass: m/z 459 (M+–H);
IR (KBr, cm–1): 3313, 2982, 1674.7, 1601, 1507.5, 1232.7;
1H NMR (600 MHz, DMSO-d6) δ 7.87 (s, 1H), 7.80 (dd, J = 1.8 Hz, 1H), 7.61–7.58 (m, 2H), 7.33 (d, J = 8.4 Hz, 1H), 7.29 (d, J = 3.6 Hz, 1H), 7.21–7.18 (m, 2H), 6.84 (d, J = 3.6 Hz, 1H), 5.17 (dd, J = 3.6, 3.0 Hz, 1H), 5.02 (d, J = 6.6 Hz, 1H), 4.57 (d, J = 4.8 Hz, 1H), 4.43–4.39 (m, 3H), 4.22 (s, 2H), 4.02–4.01 (m, 1H), 3.53–3.51 (m, 3H), 3.38–3.37 (m, 1H), 2.35 (s, 3H);
13C NMR (101 MHz, DMSO-d6) δ 199.7, 162.6, 160.2, 142.8, 142.1, 140.5, 138.8, 133.3, 130.5, 130.4, 130.4, 129.3, 127.2, 127.0, 127.0, 126.7, 123.5, 116.0, 115.8, 75.2, 72.3, 71.8, 71.3, 63.2, 33.2, 19.2.
HRMS (ESI): calcd m/zfor [C24H25FO6S + Na]+ = 483.1248, found m/z 483.1244.
Org. Process Res. Dev., Article ASAP
DOI: 10.1021/acs.oprd.7b00281

References

  1. “U.S. FDA approves Johnson & Johnson diabetes drug, canagliflozin”. Reuters. Mar 29, 2013. U.S. health regulators have approved a new diabetes drug from Johnson & Johnson, making it the first in its class to be approved in the United States.
WO2005012326A1 Jul 30, 2004 Feb 10, 2005 Tanabe Seiyaku Co Novel compounds having inhibitory activity against sodium-dependant transporter
WO2013064909A2 * Oct 30, 2012 May 10, 2013 Scinopharm Taiwan, Ltd. Crystalline and non-crystalline forms of sglt2 inhibitors
CN103655539A * Dec 13, 2013 Mar 26, 2014 重庆医药工业研究院有限责任公司 Oral solid preparation of canagliflozin and preparation method thereof
US7943582 Dec 3, 2007 May 17, 2011 Mitsubishi Tanabe Pharma Corporation Crystalline form of 1-(β-D-glucopyransoyl)-4-methyl-3-[5-(4-fluorophenyl)-2- thienylmethyl]benzene hemihydrate
US7943788 Jan 31, 2005 May 17, 2011 Mitsubishi Tanabe Pharma Corporation Glucopyranoside compound
US8513202 May 9, 2011 Aug 20, 2013 Mitsubishi Tanabe Pharma Corporation Crystalline form of 1-(β-D-glucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2-thienylmethyl]benzene hemihydrate
US20130237487 Oct 30, 2012 Sep 12, 2013 Scinopharm Taiwan, Ltd. Crystalline and non-crystalline forms of sglt2 inhibitors
WO2008002824A1 * Jun 21, 2007 Jan 3, 2008 Squibb Bristol Myers Co Crystalline solvates and complexes of (is) -1, 5-anhydro-l-c- (3- ( (phenyl) methyl) phenyl) -d-glucitol derivatives with amino acids as sglt2 inhibitors for the treatment of diabetes
US6774112 * Apr 8, 2002 Aug 10, 2004 Bristol-Myers Squibb Company Amino acid complexes of C-aryl glucosides for treatment of diabetes and method
US20090143316 * Apr 4, 2007 Jun 4, 2009 Astellas Pharma Inc. Cocrystal of c-glycoside derivative and l-proline
US20110087017 * Oct 14, 2010 Apr 14, 2011 Vittorio Farina Process for the preparation of compounds useful as inhibitors of sglt2
US20110098240 * Aug 15, 2008 Apr 28, 2011 Boehringer Ingelheim International Gmbh Pharmaceutical composition comprising a sglt2 inhibitor in combination with a dpp-iv inhibitor
Reference
1 * OGURA H. ET AL.: ‘5-FLUOROURACIL NUCLEOSIDES. SYNTHESIS OF A STEREO-CONTROLLED NUCLEOSIDE SYNTHESIS FROM ANHYDRO SUGARS‘ NUCLEIC ACID CHEM. vol. 4, 1991, pages 109 – 112, XP000607288
Citing Patent Filing date Publication date Applicant Title
WO2014195966A2 * May 30, 2014 Dec 11, 2014 Cadila Healthcare Limited Amorphous form of canagliflozin and process for preparing thereof
US9006188 May 23, 2014 Apr 14, 2015 Mapi Pharma Ltd. Co-crystals of dapagliflozin

////////////

FDA Approves Canagliflozin, Invokana – First in New Class of Type 2 Diabetes Drugs


CANAGLIFLOZIN

FRIDAY March 29, 2013

The first in a new class of type 2 diabetes drugs was approved Friday by the U.S. Food and Drug Administration.

Invokana (canagliflozin) tablets are to be taken, in tandem with a healthy diet and exercise, to improve blood sugar control in adults with type 2 diabetes.

Invokana belongs to a class of drugs called sodium-glucose co-transporter 2 (SGLT2) inhibitors. It works by blocking the reabsorption of glucose (sugar) by the kidney and increasing glucose excretions in urine, the FDA said in a news release.

Canagliflozin (Invokana) is drug for the treatment of type 2 diabetes developed by Johnson & Johnson.[1][2] In March 2013, canagliflozin became the first in a new class of drugs for diabetes treatment to be approved.[3] It is an inhibitor of subtype 2 sodium-glucose transport protein (SGLT2), which is responsible for at least 90% of the glucose reabsorption in the kidney. Blocking this transporter causes blood glucose to be eliminated through the urine

  1. New J&J diabetes drug effective in mid-stage study, Jun 26, 2010
  2.  Edward C. Chao (2011). “Canagliflozin”. Drugs of the Future 36 (5): 351–357. doi:10.1358/dof.2011.36.5.1590789.
  3.  “U.S. FDA approves Johnson & Johnson diabetes drug, canagliflozin”. Reuters. Mar 29, 2013. “U.S. health regulators have approved a new diabetes drug from Johnson & Johnson, making it the first in its class to be approved in the United States.”
  4. Prous Science: Molecule of the Month November 2007

The agency told drug maker Janssen Pharmaceuticals that it must conduct five post-approval studies of the drug to determine the risk of problems such as heart disease, cancer, pancreatitis, liver abnormalities and pregnancy complications.

updated

CANAGLIFLOZIN

300px
CANAGLIFLOZIN
Canagliflozin
Canagliflozin is a highly potent and selective subtype 2 sodium-glucose transport protein (SGLT2) inhibitor to CHO- hSGLT2, CHO- rSGLT2 and CHO- mSGLT2 with IC50 of 4.4 nM, 3.7 nM and 2 nM, respectively.


M.F.C24H25FO5S
M.Wt: 444.52
CAS No: 842133-18-0
(1S)-1,5-Anhydro-1-C-[3-[[5-(4-fluorophenyl)-2-thienyl]methyl]-4-methylphenyl]-D-glucitol
1-(β-D-glucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2-thienylmethyl]benzene
NMR…..http://file.selleckchem.com/downloads/nmr/S276003-Canagliflozin-HNMR-Selleck.pdf

Canagliflozin Hemihydrate
(1S)-1,5-Anhydro-1-C-[3-[[5-(4-fluorophenyl)-2-thienyl]methyl]-4-methylphenyl]-D-glucitol hydrate (2:1)
928672-86-0

Canagliflozin (INN, trade name Invokana) is a drug of the gliflozin class, used for the treatment of type 2 diabetes.[1][2] It was developed by Mitsubishi Tanabe Pharma and is marketed under license by Janssen, a division of Johnson & Johnson.[3]
U.S. Patent No, 7,943,788 B2 (the ‘788 patent) discloses canagliflozin or salts thereof and the process for its preparation.
U.S. Patent Nos. 7,943,582 B2 and 8,513,202 B2 discloses crystalline form of 1 -(P-D-glucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2-thienylmethyl] benzene hemihydrate and process for preparation thereof. The US ‘582 B2 and US ‘202 B2 further discloses that preparation of the crystalline form of hemi-hydrate canagliflozin typically involves dissolving in a good solvent (e.g. ketones or esters) crude or amorphous compound prepared in accordance with the procedures described in WO 2005/012326 pamphlet, and adding water and a poor solvent (e.g. alkanes or ethers) to the resulting solution, followed by filtration.
U.S. PG-Pub. No. 2013/0237487 Al (the US ‘487 Al) discloses amorphous dapagliflozin and amorphous canagliflozin. The US ‘487 Al also discloses 1:1 crystalline complex of canagliflozin with L-proline (Form CS1), ethanol solvate of a 1: 1 crystalline complex of canagliflozin with D-proline (Form CS2), 1 :1 crystalline complex of canagliflozin with L-phenylalanine (Form CS3), 1:1 crystalline complex of canagliflozin with D-proline (Form CS4).
The US ‘487 Al discloses preparation of amorphous canagliflozin by adding its heated toluene solution into n-heptane. After drying in vacuo the product was obtained as a white solid of with melting point of 54.7°C to 72.0°C. However, upon repetition of the said experiment, the obtained amorphous canagliflozin was having higher amount of residual solvents. Therefore, the amorphous canagliflozin obtained by process as disclosed in US ‘487 Al is not suitable for pharmaceutical preparations.
The US ‘487 Al further discloses that amorphous canagliflozin obtained by the above process is hygroscopic in nature which was confirmed by Dynamic vapor sorption (DVS) analysis. Further, it was observed that the amorphous form underwent a physical change between the sorption/desorption cycle, making the sorption/desorption behavior different between the two cycles. The physical change that occurred was determined to be a conversion or partial conversion from the amorphous state to a crystalline state. This change was supported by a change in the overall appearance of the sample as the humidity increased from 70% to 90% RH.
The canagliflozin assessment report EMA/718531/2013 published by EMEA discloses that Canagliflozin hemihydrate is a white to off-white powder^ practically insoluble in water and freely soluble in ethanol and non-hygroscopic. Polymorphism has been observed for canagliflozin and the manufactured Form I is a hemihydrate, and an unstable amorphous Form II. Form I is consistently produced by the proposed commercial synthesis process. Therefore, it is evident from the prior art that the reported amorphous form of canagliflozin is unstable and hygroscopic as well as not suitable for pharmaceutical preparations due to higher amount of residual solvents above the ICH acceptable limits.
Medical use

    1. Canagliflozin is an antidiabetic drug used to improve glycemic control in people with type 2 diabetes. In extensive clinical trials, canagliflozin produced a consistent dose-dependent reduction in HbA1c of 0.77% to 1.16% when administered as monotherapy, combination with metformin, combination with metformin & Sulfonyulrea, combination with metformin & pioglitazone and In combination with insulin from a baselines of 7.8% to 8.1%, in combination with metformin, or in combination with metformin and a sulfonylurea. When added to metformin Canagliflozin 100mg was shown to be non-inferior to both Sitagliptin 100mg and glimiperide in reductions on HbA1c at one year, whilst canagliflozin 300mg successfully demontrated statistical superiority over both Sitagliptin and glimiperide in HbA1c reductions. Secondary efficacy endpoint of superior body weight reduction and blood pressure reduction (versus Sitagliptin and glimiperide)) were observed as well. Canagliflozin produces beneficial effects on HDL cholesterol whilst increasing LDL cholesterol to produce no change in total cholesterol.[4][5]

      Contraindications

      Canagliflozin has proven to be clinically effective in people with moderate renal failure and treatment can be continued in patients with renal impairment.

      Adverse effects

      Canagliflozin, as is common with all sglt2 inhibitors, increased (generally mild) urinary tract infections, genital fungal infections, thirst,[6] LDL cholesterol, and was associated with increased urination and episodes of low blood pressure.
      There are concerns it may increase the risk of diabetic ketoacidosis.[7]
      Cardiovascular problems have been discussed with this class of drugs.[citation needed] The pre-specified endpoint for cardiovascular safety in the canagliflozin clinical development program was Major Cardiovascular Events Plus (MACE-Plus), defined as the occurrence of any of the following events: cardiovascular death, non-fatal myocardial infarction, non-fatal stroke, or unstable angina leading to hospitalization. This endpoint occurred in more people in the placebo group (20.5%) than in the canagliflozin treated group (18.9%).
      Nonetheless, an FDA advisory committee expressed concern regarding the cardiovascular safety of canagliflozin. A greater number of cardiovascular events was observed during the first 30 days of treatment in canagliflozin treated people (0.45%) relative to placebo treated people (0.07%), suggesting an early period of enhanced cardiovascular risk. In addition, there was an increased risk of stroke in canagliflozin treated people. However none of these effects were seen as statistically significant. Additional cardiovascular safety data from the ongoing CANVAS trial is expected in 2015.[8]

      Interactions

      The drug may increase the risk of dehydration in combination with diuretic drugs.
      Because it increases renal excretion of glucose, treatment with canagliflozin prevents renal reabsorption of 1,5-anhydroglucitol, leading to artifactual decreases in serum 1,5-anhydroglucitol; it can therefore interfere with the use of serum 1,5-anhydroglucitol (assay trade name, GlycoMark) as a measure of postprandial glucose excursions.[9]

      Mechanism of action

      Canagliflozin is an inhibitor of subtype 2 sodium-glucose transport protein (SGLT2), which is responsible for at least 90% of the renal glucose reabsorption (SGLT1 being responsible for the remaining 10%). Blocking this transporter causes up to 119 grams of blood glucose per day to be eliminated through the urine,[10] corresponding to 476 kilocalories. Additional water is eliminated by osmotic diuresis, resulting in a lowering of blood pressure.
      This mechanism is associated with a low risk of hypoglycaemia (too low blood glucose) compared to other antidiabetic drugs such as sulfonylurea derivatives and insulin.[11]

      History

      On July 4, 2011, the European Medicines Agency approved a paediatric investigation plan and granted both a deferral and a waiver for canagliflozin (EMEA-001030-PIP01-10) in accordance with EC Regulation No.1901/2006 of the European Parliament and of the Council.[12]
      In March 2013, canagliflozin became the first SGLT2 inhibitor to be approved in the United States.[13]
      SYNTHESIS

…………
CANA1CANA2

………….

Canagliflozin is an API that is an inhibitor of SGLT2 and is being developed for the treatment of type 2 diabetes mellitus.[0011] The IUPAC systematic name of canagliflozin is (25,,3/?,4i?,55′,6 ?)-2-{3-[5-[4-fluoro- phenyl)-thiophen-2-ylmethyl]-4-methyl-phenyl}-6-hydroxymethyl-tetrahydro-pyran-3,4,5-triol, and is also known as (15)-l,5-anhydro-l-C-[3-[[5-(4-fluorophenyl)-2-thienyl]methyl]-4- methylphenyl]-D-glucitol and l-( -D-glucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2- thienylmethyl]benzene. Canagliflozin is a white to off-white powder with a molecular formula of C24H25F05S and a molecular weight of 444.52. The structure of canagliflozin is shown as compound B.

Compound B – Canagliflozin
[0012] In US 2008/0146515 Al, a crystalline hemihydrate form of canagliflozin (shown as Compound C) is disclosed, having the powder X-ray diffraction (XRPD) pattern comprising the following 2Θ values measured using CuKa radiation: 4.36±0.2, 13.54±0.2, 16.00±0.2, 19.32±0.2, and 20.80±0.2. The XRPD pattern is shown in Figure 24. A process for the preparation of canagliflozin hemihydrate is also disclosed in US 2008/0146515 Al.

Compound C – hemihydrate form of canagliflozin
[0013] In US 2009/0233874 Al, a crystalline form of canagliflozin is disclosed.

……..

WO 2005/012326 pamphlet discloses a class of compounds that are inhibitors of sodium-dependent glucose transporter (SGLT) and thus of therapeutic use for treatment of diabetes, obesity, diabetic complications, and the like. There is described in WO 2005/012326 pamphlet 1-(β-D-glucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2-thienylmethyl]benzene of formula (I):

Example 1 Crystalline 1-(β-D-glucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2-thienylmethyl]benzene hemihydrate1-(β-D-glucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2-thienylmethyl]benzene was prepared in a similar manner as described in WO 2005/012326.

(1) To a solution of 5-bromo-1-[5-(4-fluorophenyl)-2-thienylmethyl]-2-methylbenzene (1, 28.9 g) in tetrahydrofuran (480 ml) and toluene (480 ml) was added n-butyllithium (1.6M hexane solution, 50.0 ml) dropwise at −67 to −70° C. under argon atmosphere, and the mixture was stirred for 20 minutes at the same temperature. Thereto was added a solution of 2 (34.0 g) in toluene (240 ml) dropwise at the same temperature, and the mixture was further stirred for 1 hour at the same temperature. Subsequently, thereto was added a solution of methanesulfonic acid (21.0 g) in methanol (480 ml) dropwise, and the resulting mixture was allowed to warm to room temperature and stirred for 17 hours. The mixture was cooled under ice—water cooling, and thereto was added a saturated aqueous sodium hydrogen carbonate solution. The mixture was extracted with ethyl acetate, and the combined organic layer was washed with brine and dried over magnesium sulfate. The insoluble was filtered off and the solvent was evaporated under reduced pressure. The residue was triturated with toluene (100 ml)—hexane (400 ml) to give 1-(1-methoxyglucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2-thienylmethyl]-benzene (3) (31.6 g). APCI-Mass m/Z 492 (M+NH4).
(2) A solution of 3 (63.1 g) and triethylsilane (46.4 g) in dichloromethane (660 ml) was cooled by dry ice-acetone bath under argon atmosphere, and thereto was added dropwise boron trifluoride•ethyl ether complex (50.0 ml), and the mixture was stirred at the same temperature. The mixture was allowed to warm to 0° C. and stirred for 2 hours. At the same temperature, a saturated aqueous sodium hydrogen carbonate solution (800 ml) was added, and the mixture was stirred for 30 minutes. The organic solvent was evaporated under reduced pressure, and the residue was poured into water and extracted with ethyl acetate twice. The organic layer was washed with water twice, dried over magnesium sulfate and treated with activated carbon. The insoluble was filtered off and the solvent was evaporated under reduced pressure. The residue was dissolved in ethyl acetate (300 ml), and thereto were added diethyl ether (600 ml) and H2O (6 ml). The mixture was stirred at room temperature overnight, and the precipitate was collected, washed with ethyl acetate-diethyl ether (1:4) and dried under reduced pressure at room temperature to give 1-(β-D-glucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2-thienylmethyl]benzene hemihydrate (33.5 g) as colorless crystals.
mp 98-100° C. APCI-Mass m/Z 462 (M+NH4). 1H-NMR (DMSO-d6) δ 2.26 (3H, s), 3.13-3.28 (4H, m), 3.44 (1H, m), 3.69 (1H, m), 3.96 (1H, d, J=9.3 Hz), 4.10, 4.15 (each 1H, d, J=16.0 Hz), 4.43 (1H, t, J=5.8 Hz), 4.72 (1H, d, J=5.6 Hz), 4.92 (2H, d, J=4.8 Hz), 6.80 (1H, d, J=3.5 Hz), 7.11-7.15 (2H, m), 7.18-7.25 (3H, m), 7.28 (1H, d, J=3.5 Hz), 7.59 (2H, dd, J=8.8, 5.4 Hz).
Anal. Calcd. for C24H25FO5S.0.5H2O: C, 63.56; H, 5.78; F, 4.19; S, 7.07. Found: C, 63.52; H, 5.72; F, 4.08; S, 7.00.
1-(β-D-glucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2-thienylmethyl]benzene
Figure US07943582-20110517-C00001

Example 2An amorphous powder of 1-(β-D-glucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2-thienylmethyl]benzene (1.62 g) was dissolved in acetone (15 ml), and thereto were added H2O (30 ml) and a crystalline seed. The mixture was stirred at room temperature for 18 hours, and the precipitate was collected, washed with acetone—H2O (1:4, 30 ml) and dried under reduced pressure at room temperature to give 1-(β-D-glucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2-thienylmethyl]benzene hemihydrate (1.52 g) as colorless crystals. mp 97-100° C.

……..

there are a significant number of other β-C-arylglucoside derived drug candidates, most of which differ only in the aglycone moiety (i.e., these compounds comprise a central 1-deoxy-glucose ring moiety that is arylated at CI). It is this fact that makes them attractive targets for a novel synthetic platform technology, since a single methodology should be able to furnish a plurality of products. Among β-C-arylglucosides that possess known SGLT2 inhibition also currently in clinical development are canagliflozin, empagliflozin, and ipragliflozin.

Dapagliflozin                             Canagliflozin

Ipragliflozin …………………Empagliflozin
[0007] A series of synthetic methods have been reported in the peer-reviewed and patent literature that can be used for the preparation of β-C-arylglucosides. These methods are described below and are referred herein as the gluconolactone method, the metalated glucal method, the glucal epoxide method and the glycosyl leaving group substitution method.
[0008] The gluconolactone method: In 1988 and 1989 a general method was reported to prepare C-arylglucosides from tetra-6>-benzyl protected gluconolactone, which is an oxidized derivative of glucose (see J. Org. Chem. 1988, 53, 752-753 and J. Org. Chem. 1989, 54, 610- 612). The method comprises: 1) addition of an aryllithium derivative to the hydroxy-protected gluconolactone to form a hemiketal (a.k.ci., a lactol), and 2) reduction of the resultant hemiketal with triethylsilane in the presence of boron trifluoride etherate. Disadvantages of this classical, but very commonly applied method for β-C-arylglucoside synthesis include:
1) poor “redox economy” (see J. Am. Chem. Soc. 2008, 130, 17938-17954 and Anderson, N. G. Practical Process Research & Development, 1st Ed.; Academic Press, 2000 (ISBN- 10: 0120594757); pg 38)— that is, the oxidation state of the carbon atom at CI, with respect to glucose, is oxidized in the gluconolactone and then following the arylation step is reduced to provide the requisite oxidation state of the final product. 2) due to a lack of stereospecificity, the desired β-C-arylglucoside is formed along with the undesired a-C-arylglucoside stereoisomer (this has been partially addressed by the use of hindered trialkylsilane reducing agents (see Tetrahedron: Asymmetry 2003, 14, 3243-3247) or by conversion of the hemiketal to a methyl ketal prior to reduction (see J. Org. Chem. 2007, 72, 9746-9749 and U.S. Patent 7,375,213)).
Oxidation Reduction

Glucose Gluconoloctone Hemiketal a-anomer β-anomer
R = protecting group
[0009] The metalated glucal method: U.S. Patent 7,847,074 discloses preparation of SGLT2 inhibitors that involves the coupling of a hydroxy-protected glucal that is metalated at CI with an aryl halide in the presence of a transition metal catalyst. Following the coupling step, the requisite formal addition of water to the C-arylglucal double bond to provide the desired C-aryl glucoside is effected using i) hydroboration and oxidation, or ii) epoxidation and reduction, or iii) dihydroxylation and reduction. In each case, the metalated glucal method represents poor redox economy because oxidation and reduction reactions must be conducted to establish the requisite oxidation states of the individual CI and C2 carbon atoms.
[0010] U.S. Pat. Appl. 2005/0233988 discloses the utilization of a Suzuki reaction between a CI -boronic acid or boronic ester substituted hydroxy-protected glucal and an aryl halide in the presence of a palladium catalyst. The resulting 1- C-arylglucal is then formally hydrated to provide the desired 1- C-aryl glucoside skeleton by use of a reduction step followed by an oxidation step. The synthesis of the boronic acid and its subsequent Suzuki reaction, reduction and oxidation, together, comprise a relatively long synthetic approach to C-arylglucosides and exhibits poor redox economy. Moreover, the coupling catalyst comprises palladium which is toxic and therefore should be controlled to very low levels in the drug substance.

R = protecting group; R’ = H or alkyl
[0011] The glucal epoxide method: U.S. Patent 7,847,074 discloses a method that utilizes an organometallic (derived from the requisite aglycone moiety) addition to an electrophilic epoxide located at C1-C2 of a hydroxy-protected glucose ring to furnish intermediates useful for SGLT2 inhibitor synthesis. The epoxide intermediate is prepared by the oxidation of a hydroxy- protected glucal and is not particularly stable. In Tetrahedron 2002, 58, 1997-2009 it was taught that organometallic additions to a tri-6>-benzyl protected glucal-derived epoxide can provide either the a-C-arylglucoside, mixtures of the a- and β-C-arylglucoside or the β-C-arylglucoside by selection of the appropriate counterion of the carbanionic aryl nucleophile (i.e., the
organometallic reagent). For example, carbanionic aryl groups countered with copper (i.e., cuprate reagents) or zinc (i.e., organozinc reagents) ions provide the β-C-arylglucoside, magnesium ions provide the a- and β-C-arylglucosides, and aluminum (i.e., organoaluminum reagents) ions provide the a-C-arylglucoside.

or Zn[0012] The glycosyl leaving group substitution method: U.S. Patent 7,847,074, also disclosed a method comprising the substitution of a leaving group located at CI of a hydroxy-protected glucosyl species, such as a glycosyl halide, with a metalated aryl compound to prepare SGLT2 inhibitors. U.S. Pat. Appl. 2011/0087017 disclosed a similar method to prepare the SGLT2 inhibitor canagliflozin and preferably diarylzinc complexes are used as nucleophiles along with tetra- >-pivaloyl protected glucosylbromide.

Glucose Glucosyl bromide β-anomer
[0013] Methodology for alkynylation of 1,6-anhydroglycosides reported in Helv. Chim. Acta. 1995, 78, 242-264 describes the preparation of l,4-dideoxy-l,4-diethynyl^-D-glucopyranoses (a. La., glucopyranosyl acetylenes), that are useful for preparing but-l,3-diyne-l,4-diyl linked polysaccharides, by the ethynylating opening (alkynylation) of partially protected 4-deoxy-4-C- ethynyl-l,6-anhydroglucopyranoses. The synthesis of β-C-arylglucosides, such as could be useful as precursors for SLGT2 inhibitors, was not disclosed. The ethynylation reaction was reported to proceed with retention of configuration at the anomeric center and was rationalized (see Helv. Chim. Acta 2002, 85, 2235-2257) by the C3-hydroxyl of the 1,6- anhydroglucopyranose being deprotonated to form a C3-0-aluminium species, that coordinated with the C6-oxygen allowing delivery of the ethyne group to the β-face of the an oxycarbenium cation derivative of the glucopyranose. Three molar equivalents of the ethynylaluminium reagent was used per 1 molar equivalent of the 1,6-anhydroglucopyranose. The
ethynylaluminium reagent was prepared by the reaction of equimolar (i.e., 1:1) amounts of aluminum chloride and an ethynyllithium reagent that itself was formed by the reaction of an acetylene compound with butyllithium. This retentive ethynylating opening method was also applied (see Helv. Chim. Acta. 1998, 81, 2157-2189) to 2,4-di-<9-triethylsilyl- 1,6- anhydroglucopyranose to provide l-deoxy-l-C-ethynyl- -D-glucopyranose. In this example, 4 molar equivalents of the ethynylaluminium reagent was used per 1 molar equivalent of the 1,6- anhydroglucopyranose. The ethynylaluminium regent was prepared by the reaction of equimolar (i.e., 1: 1) amounts of aluminum chloride and an ethynyl lithium reagent that itself was formed by reaction of an acetylene compound with butyllithium.
[0014] It can be seen from the peer-reviewed and patent literature that the conventional methods that can be used to provide C-arylglucosides possess several disadvantages. These include (1) a lack of stereoselectivity during formation of the desired anomer of the C- arylglucoside, (2) poor redox economy due to oxidation and reduction reaction steps being required to change the oxidation state of CI or of CI and C2 of the carbohydrate moiety, (3) some relatively long synthetic routes, (4) the use of toxic metals such as palladium, and/or (5) atom uneconomic protection of four free hydroxyl groups. With regard to the issue of redox economy, superfluous oxidation and reduction reactions that are inherently required to allow introduction of the aryl group into the carbohydrate moiety of the previously mention synthetic methods and the subsequent synthetic steps to establish the required oxidation state, besides adding synthetic steps to the process, are particular undesirable for manufacturing processes because reductants can be difficult and dangerous to operate on large scales due to their flammability or ability to produce flammable hydrogen gas during the reaction or during workup, and because oxidants are often corrosive and require specialized handling operations (see Anderson, N. G. Practical Process Research & Development, 1st Ed.; Academic Press, 2000 (ISBN-10: 0120594757); pg 38 for discussions on this issue).
[0015] In view of the above, there remains a need for a shorter, more efficient and
stereoselective, redox economic process for the preparation of β-C-arylglucosides. A new process should be applicable to the industrial manufacture of SGLT2 inhibitors and their prodrugs,
EXAMPLE 22 – Synthesis of 2,4-di-0-feri-butyldiphenylsUyl-l-C-(3-((5-(4- fluorophenyl)thiophen-2-yl)methyl)-4-methylphenyl)- -D-glucopyranoside (2,4-di-6>-TBDPS- canagliflozin; (IVi”))

[0227] 2-(5-Bromo-2-methylbenzyl)-5-(4-fluorophenyl)thiophene (1.5 g, 4.15 mmol) and magnesium powder (0.33 g, 13.7 mmol) were placed in a suitable reactor, followed by THF (9 mL) and 1,2-dibromoethane (95 μί). The mixture was heated to reflux. After the reaction was initiated, a solution of 2-(5-bromo-2-methylbenzyl)-5-(4-fluorophenyl)thiophene (2.5 g, 6.92 mmol) in THF (15mL) was added dropwise. The mixture was stirred for another 2 hours under reflux, and was then cooled to ambient temperature and titrated to determine the concentration. The thus prepared 3-[[5-(4-fluorophenyl)-2-thienyl]methyl]-4-methylphenyl magnesium bromide (0.29 M in THF, 17 mL, 5.0 mmol) and A1C13 (0.5 M in THF, 4.0 mL, 2.0 mmol) were mixed at ambient temperature to give a black solution, which was stirred at ambient temperature for 1 hour. To a solution of l ,6-anhydro-2,4-di-6>-ieri-butyldiphenylsilyl- -D-glucopyranose (0.64 g, 1.0 mmol) in PhOMe (3.0 mL) at ambient temperature was added rc-BuLi (0.4 mL, 1.0 mmol, 2.5 M solution in Bu20). After stirring for about 5 min the solution was then added into the above prepared aluminum mixture via syringe, followed by additional PhOMe (1.0 mL) to rinse the flask. The mixture was concentrated under reduced pressure (50 torr) at 60 °C (external bath temperature) to remove low-boiling point ethereal solvents, and PhOMe (6 mL) was then added. The remaining mixture was heated at 150 °C (external bath temperature) for 5 hours at which time HPLC assay analysis indicated a 68% yield of 2,4-di-6>-ieri-butyldiphenylsilyl-l-C-(3-((5- (4-fluorophenyl)thiophen-2-yl)methyl)-4-methylphenyl)- -D-glucopyranoside. After cooling to ambient temperature, the reaction was treated with 10% aqueous NaOH (1 mL), THF (10 mL) and diatomaceous earth at ambient temperature, then the mixture was filtered and the filter cake was washed with THF. The combined filtrates were concentrated and the crude product was purified by silica gel column chromatography (eluting with 1 :20 MTBE/rc-heptane) to give the product 2,4-di-6>-ieri-butyldiphenylsilyl-l-C-(3-((5-(4-fluorophenyl)thiophen-2-yl)methyl)-4- methylphenyl)- -D-glucopyranoside (0.51 g, 56%) as a white powder.
1H NMR (400 MHz, CDC13) δ 7.65 (d, J= 7.2 Hz, 2H), 7.55 (d, J= 7.2 Hz, 2H), 7.48 (dd, J= 7.6, 5.6 Hz, 2H), 7.44-7.20 (m, 16H), 7.11-6.95 (m, 6H), 6.57 (d, J= 3.2 Hz, IH), 4.25 (d, J= 9.6 Hz, IH), 4.06 (s, 2H), 3.90-3.86 (m, IH), 3.81-3.76 (m, IH), 3.61-3.57 (m, IH), 3.54-3.49 (m, 2H), 3.40 (dd, J= 8.8, 8.8 Hz, IH), 2.31 (s, 3H), 1.81 (dd, J= 6.6, 6.6 Hz, IH, OH), 1.19 (d, J= 4.4 Hz, IH, OH), 1.00 (s, 9H), 0.64 (s, 9H); 13C NMR (100 MHz, CDC13) δ 162.1 (d, J= 246 Hz, C), 143.1 (C), 141.4 (C), 137.9 (C), 136.8 (C), 136.5 (C), 136.4 (CH x2), 136.1 (CH x2), 135.25 (C), 135.20 (CH x2), 135.0 (CH x2), 134.8 (C), 132.8 (C), 132.3 (C), 130.9 (d, J= 3.5 Hz, C), 130.5 (CH), 130.0 (CH), 129.7 (CH), 129.5 (CH), 129.4 (CH), 129.2 (CH), 127.6 (CH x4), 127.5 (CH x2), 127.2 (CH x2), 127.1 (d, J= 8.2 Hz, CH x2), 127.06 (CH), 126.0 (CH), 122.7 (CH), 115.7 (d, J= 21.8 Hz, CH x2), 82.7 (CH), 80.5 (CH), 79.4 (CH), 76.3 (CH), 72.9 (CH), 62.8 (CH2), 34.1(CH2), 27.2 (CH3 x3), 26.7 (CH3 x3), 19.6, (C), 19.3 (CH3),19.2 (C); LCMS (ESI) m/z 938 (100, [M+NH4]+), 943 (10, [M+Na]+).
EXAMPLE 23 – Synthesis of canagliflozin (l-C-(3-((5-(4-fluorophenyl)thiophen-2-yl)methyl)- 4-methylphenyl)- -D-glucopyranoside; (Ii))

[0228] A mixture of the 2,4-di-6>-ieri-butyldiphenylsilyl-l-C-(3-((5-(4-fluorophenyl)thiophen- 2-yl)methyl)-4-methylphenyl)- -D-glucopyranoside (408 mg, 0.44 mmol) and TBAF (3.5 mL, 3.5 mmol, 1.0 M in THF) was stirred at ambient temperature for 4 hours. CaC03 (0.73 g), Dowex 50WX8-400 ion exchange resin (2.2 g) and MeOH (5mL) were added to the product mixture and the suspension was stirred at ambient temperature for 1 hour and then the mixture was filtered through a pad of diatomaceous earth. The filter cake was rinsed with MeOH and the combined filtrates was evaporated under vacuum and the resulting residue was purified by column chromatography (eluting with 1 :20 MeOH/DCM) affording canagliflozin (143 mg, 73%).

1H NMR (400 MHz, DMSO-J6) δ 7.63-7.57 (m, 2H), 7.28 (d, J= 3.6 Hz, 1H), 7.23-7.18 (m, 3H), 7.17-7.12 (m, 2H), 6.80 (d, J= 3.6 Hz, 1H), 4.93 (br, 2H, OH), 4.73 (br, 1H, OH), 4.44 (br,IH, OH), 4.16 (d, J= 16 Hz, 1H), 4.10 (d, J= 16 Hz, 1H), 3.97 (d, J= 9.2 Hz, 1H), 3.71 (d, J=I I.6 Hz, 1H), 3.47-3.43 (m, 1H), 3.30-3.15 (m, 4H), 2.27 (s, 3H);

13C NMR (100 MHz, DMSO- d6) δ 161.8 (d, J= 243 Hz, C), 144.1 (C), 140.7 (C), 138.7 (C), 137.8 (C), 135.4 (C), 131.0 (d, J= 3.1 Hz, C), 130.1 (CH), 129.5 (CH), 127.4 (d, J= 8.1 Hz, CH x2), 126.8 (CH), 126.7 (CH), 123.9 (CH), 116.4 (d, J= 21.6 Hz, CH x2), 81.8 (CH), 81.7 (CH), 79.0 (CH), 75.2 (CH), 70.9 (CH), 61.9 (CH2), 33.9 (CH2), 19.3 (CH3);

LCMS (ESI) m/z 462 (100, [M+NH4]+), 467 (3, [M+Na]+).

Example 1 – Synthesis of l,6-anhydro-2,4-di-6>-ieri-butyldiphenylsilyl- -D-glucopyranose (II”)

III II”
[0206] To a suspension solution of l,6-anhydro- -D-glucopyranose (1.83 g, 11.3 mmol) and imidazole (3.07 g, 45.2 mmol) in THF (10 mL) at 0 °C was added dropwise a solution of TBDPSC1 (11.6 mL, 45.2 mmol) in THF (10 mL). After the l,6-anhydro-P-D-gJucopyranose was consumed, water (10 mL) was added and the mixture was extracted twice with EtOAc (20 mL each), washed with brine (10 mL), dried (Na2S04) and concentrated. Column
chromatography (eluting with 1 :20 EtOAc/rc-heptane) afforded 2,4-di-6>-ieri-butyldiphenylsilyl- l,6-anhydro- “D-glucopyranose (5.89 g, 81%).
1H NMR (400 MHz, CDC13) δ 7.82-7.70 (m, 8H), 7.49-7.36 (m, 12H), 5.17 (s, IH), 4.22 (d, J= 4.8 Hz, IH), 3.88-3.85 (m, IH), 3.583-3.579 (m, IH), 3.492-3.486 (m, IH), 3.47-3.45 (m, IH), 3.30 (dd, J= 7.4, 5.4 Hz, IH), 1.71 (d, J= 6.0 Hz, IH), 1.142 (s, 9H), 1.139 (s, 9H); 13C NMR (100 MHz, CDCI3) δ 135.89 (CH x2), 135.87 (CH x2), 135.85 (CH x2), 135.83 (CH x2), 133.8 (C), 133.5 (C), 133.3 (C), 133.2 (C), 129.94 (CH), 129.92 (CH), 129.90 (CH), 129.88 (CH), 127.84 (CH2 x2), 127.82 (CH2 x2), 127.77 (CH2 x4), 102.4 (CH), 76.9 (CH), 75.3 (CH), 73.9 (CH), 73.5 (CH), 65.4 (CH2), 27.0 (CH3 x6), 19.3 (C x2).

……..
FIG. 1:
X-ray powder diffraction pattern of the crystalline of hemihydrate of the compound of formula (I).
FIG. 2:
Infra-red spectrum of the crystalline of hemihydrate of the compound of formula (I).http://www.google.com/patents/US7943582
………….
FIGS. 3 and 4 provide the XRPD pattern and IR spectrum, respectively, of amorphous canagliflozin.
………………
Canagliflozin
300px
Systematic (IUPAC) name
(2S,3R,4R,5S,6R)-2-{3-[5-[4-Fluoro-phenyl)-thiophen-2-ylmethyl]-4-methyl-phenyl}-6-hydroxymethyl-tetrahydro-pyran-3,4,5-triol
Clinical data
Trade names Invokana
AHFS/Drugs.com entry
Pregnancy
category
  • US:C (Risk not ruled out)
Legal status
Routes of
administration
Oral
Pharmacokinetic data
Bioavailability 65%
Protein binding 99%
Metabolism Hepaticglucuronidation
Biological half-life 11.8 (10–13) hours
Excretion Fecal and 33% renal
Identifiers
CAS Registry Number 842133-18-0 Yes
ATC code A10BX11
PubChem CID: 24812758
IUPHAR/BPS 4582
DrugBank DB08907 Yes
ChemSpider 26333259 
UNII 6S49DGR869 
ChEBI CHEBI:73274 
ChEMBL CHEMBL2103841 
Synonyms JNJ-28431754; TA-7284; (1S)-1,5-anhydro-1-C-[3-[[5-(4-fluorophenyl)-2-thienyl]methyl]-4-methylphenyl]-D-glucitol
Chemical data
Formula C24H25FO5S
Molecular mass 444.52 g/mol

References

  1. “U.S. FDA approves Johnson & Johnson diabetes drug, canagliflozin”. Reuters. Mar 29, 2013. U.S. health regulators have approved a new diabetes drug from Johnson & Johnson, making it the first in its class to be approved in the United States.
WO2005012326A1 Jul 30, 2004 Feb 10, 2005 Tanabe Seiyaku Co Novel compounds having inhibitory activity against sodium-dependant transporter
WO2013064909A2 * Oct 30, 2012 May 10, 2013 Scinopharm Taiwan, Ltd. Crystalline and non-crystalline forms of sglt2 inhibitors
CN103655539A * Dec 13, 2013 Mar 26, 2014 重庆医药工业研究院有限责任公司 Oral solid preparation of canagliflozin and preparation method thereof
US7943582 Dec 3, 2007 May 17, 2011 Mitsubishi Tanabe Pharma Corporation Crystalline form of 1-(β-D-glucopyransoyl)-4-methyl-3-[5-(4-fluorophenyl)-2- thienylmethyl]benzene hemihydrate
US7943788 Jan 31, 2005 May 17, 2011 Mitsubishi Tanabe Pharma Corporation Glucopyranoside compound
US8513202 May 9, 2011 Aug 20, 2013 Mitsubishi Tanabe Pharma Corporation Crystalline form of 1-(β-D-glucopyranosyl)-4-methyl-3-[5-(4-fluorophenyl)-2-thienylmethyl]benzene hemihydrate
US20130237487 Oct 30, 2012 Sep 12, 2013 Scinopharm Taiwan, Ltd. Crystalline and non-crystalline forms of sglt2 inhibitors
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Reference
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1H NMR PREDICT

  13C NMR PREDICT

  COSY PREDICT

update……..

Figure

CAS 1672658-93-3
C24 H25 F O6 S, 460.52
D-Glucopyranose, 1-C-[3-[[5-(4-fluorophenyl)-2-thienyl]methyl]-4-methylphenyl]-
str1
str1
CAS 1809403-04-0
C24 H25 F O6 S, 460.52
D-Glucose, 1-C-[3-[[5-(4-fluorophenyl)-2-thienyl]methyl]-4-methylphenyl]-
WO2017/93949

Figure

(2R,3S,4R,5R)-1-(3-((5-(4-Fluorophenyl)thiophen-2-yl)methyl)-4-methylphenyl)-2,3,4,5,6-pentahydroxyhexan-1-one    12

From the FT-IR spectra of 12 contain a signal at 1674 cm–1, this signal is strongly indicative of a carbonyl ketone being present in 12

In 13C NMR and HMBC correlations spectra, the chemical shift at 199.75 ppm was observed. Analysis of the NMR data  confirmed that the structure of 12 is a ring-opened keto form

Synthesis of (2R,3S,4R,5R)-1-(3-((5-(4-Fluorophenyl)thiophen-2-yl)methyl)-4-methylphenyl)-2,3,4,5,6-pentahydroxyhexan-1-one 12

title compound 12 (84.23% yield) and having 99.4% purity by HPLC;
DSC: 160.84–166.44 °C;
Mass: m/z 459 (M+–H);
IR (KBr, cm–1): 3313, 2982, 1674.7, 1601, 1507.5, 1232.7;
1H NMR (600 MHz, DMSO-d6) δ 7.87 (s, 1H), 7.80 (dd, J = 1.8 Hz, 1H), 7.61–7.58 (m, 2H), 7.33 (d, J = 8.4 Hz, 1H), 7.29 (d, J = 3.6 Hz, 1H), 7.21–7.18 (m, 2H), 6.84 (d, J = 3.6 Hz, 1H), 5.17 (dd, J = 3.6, 3.0 Hz, 1H), 5.02 (d, J = 6.6 Hz, 1H), 4.57 (d, J = 4.8 Hz, 1H), 4.43–4.39 (m, 3H), 4.22 (s, 2H), 4.02–4.01 (m, 1H), 3.53–3.51 (m, 3H), 3.38–3.37 (m, 1H), 2.35 (s, 3H);
13C NMR (101 MHz, DMSO-d6) δ 199.7, 162.6, 160.2, 142.8, 142.1, 140.5, 138.8, 133.3, 130.5, 130.4, 130.4, 129.3, 127.2, 127.0, 127.0, 126.7, 123.5, 116.0, 115.8, 75.2, 72.3, 71.8, 71.3, 63.2, 33.2, 19.2.
HRMS (ESI): calcd m/zfor [C24H25FO6S + Na]+ = 483.1248, found m/z 483.1244.
Org. Process Res. Dev., Article ASAP
DOI: 10.1021/acs.oprd.7b00281

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