New Drug Approvals

Home » 2020 APPROVALS » Borofalan (10B)

Borofalan (10B)

DRUG APPROVALS BY DR ANTHONY MELVIN CRASTO .....FOR BLOG HOME CLICK HERE

ORGANIC SPECTROSCOPY

Read all about Organic Spectroscopy on ORGANIC SPECTROSCOPY INTERNATIONAL 

Categories

Recent Posts

Blog Stats

  • 3,664,227 hits

Enter your email address to follow this blog and receive notifications of new posts by email.

Join 2,653 other followers

add to any

Share

Boronophenylalanine B-10.png
ChemSpider 2D Image | Borofalan (10B) | C9H1210BNO4

Borofalan (10B), ボロファラン (10B), 硼[10B]法仑

APPROVED JAPAN, 2020/3/25, Steboronine

Antineoplastic, Diagnostic aid, Radioactive agent

(2S)-2-amino-3-(4-(10B)dihydroxy(10B)phenyl)propanoic acid

FormulaC9H12BNO4
CAS80994-59-8
Mol weight209.0069
  • 4-(Borono-10B)-L-phenylalanine
  • (10B)-4-Borono-L-phenylalanine
  • Borofalan (10b)
  • L-(p-[10B]Boronophenyl)alanine
  • L-4-[10B]Boronophenylalanine
    • p-[10B]Borono-L-phenylalanine
  • L-Phenylalanine, 4-borono-10B-
    Marketed Head and neck cancer
  • Originator Stella Pharma
  • Developer Osaka University; Stella Pharma; Sumitomo Heavy Industries
  • Class Antineoplastics; Borates; Propionic acids; Radiopharmaceuticals
  • Mechanism of Action Ionising radiation emitters
  • Phase IIGlioma
  • Phase I Haemangiosarcoma; Malignant melanoma

Borofalan (10B)

4-[(10B)Borono]-L-phenylalanine

C9H1210BNO4 : 208.21
[80994-59-8]

With the development of atomic science, radiation therapy such as cobalt hexahydrate, linear accelerator, and electron beam has become one of the main methods of cancer treatment. However, traditional photon or electron therapy is limited by the physical conditions of the radiation itself. While killing the tumor cells, it also causes damage to a large number of normal tissues on the beam path. In addition, due to the sensitivity of tumor cells to radiation, traditional radiation therapy For the more radiation-resistant malignant tumors (such as: glioblastoma multiforme, melanoma), the treatment effect is often poor.

In order to reduce the radiation damage of normal tissues around the tumor, the concept of target treatment in chemotherapy has been applied to radiation therapy; and for tumor cells with high radiation resistance, it is currently actively developing with high relative biological effects (relative Biological effectiveness, RBE) radiation sources, such as proton therapy, heavy particle therapy, neutron capture therapy. Among them, neutron capture therapy combines the above two concepts, such as boron neutron capture therapy, by the specific agglomeration of boron-containing drugs in tumor cells, combined with precise neutron beam regulation, providing better radiation than traditional radiation. Cancer treatment options.

Boron Neutron Capture Therapy (BNCT) is a high-capture cross-section of thermal neutrons using boron-containing ( 10 B) drugs, with 10 B(n,α) 7 Li neutron capture and nuclear splitting reactions. Two heavy charged particles of 4 He and 7 Li are produced. The average energy of the two charged particles is about 2.33 MeV, which has high linear energy transfer (LET) and short range characteristics. The linear energy transfer and range of α particles are 150 keV/μm and 8 μm, respectively, while the 7 Li heavy particles are For 175 keV/μm, 5 μm, the total range of the two particles is equivalent to a cell size, so the radiation damage caused to the organism can be limited to the cell level, when the boron-containing drug is selectively aggregated in the tumor cells, with appropriate The sub-radiation source can achieve the purpose of locally killing tumor cells without causing too much damage to normal tissues.

Since the effectiveness of boron neutron capture therapy depends on the concentration of boron-containing drugs in the tumor cell position and the number of thermal neutrons, it is also called binary cancer therapy; thus, in addition to the development of neutron sources, The development of boron-containing drugs plays an important role in the study of boron neutron capture therapy.

4-( 10 B)dihydroxyboryl-L-phenylalanine (4-( 10 B)borono-L-phenylalanine, L- 10 BPA) is currently known to be able to utilize boron neutron capture therapy (boron neutron capture therapy) , BNCT) An important boron-containing drug for the treatment of cancer.

Therefore, various synthetic methods of L-BPA have been developed. As shown in the following formula (A), the prior art L-BPA synthesis method includes two methods of forming a bond (a) and a bond (b):

Figure PCTCN2016094881-appb-000001

Among them, the method for synthesizing L-BPA by forming the bond (a) is to try to introduce a substituent containing a dihydroxylboryl group or a borono group into the skeleton of the phenylalanine, thereby the pair of the amide substituent. The position forms a carbon-boron bond to produce L-BPA.

J. Org. Chem. 1998, 63, 8019 discloses a method for the cross-coupling reaction of (S)-4-iodophenylalanine with a diboron compound by palladium-catalyzed amine end treatment. Amine-protected (S)-4-iodophenylalanine (eg (S)-N-tert-butoxycarbonyl-4-iodophenylalanine ((S)-N-Boc-4-) Iodophenylalanine)) is prepared by cross-coupling with a diboron compound such as bis(pinacolato diboron) to give (S)-N-tert-butoxycarbonyl-4-pentanoylboryl phenylalanine The amine-terminated (S)-4-boranyl ester phenylalanine of the acid ((S)-N-Boc-4-pinacolatoborono phenylalanine); afterwards, the protecting group on the amine end and the boronic end are removed. The above substituents complete the preparation of L-BPA.

However, since the selected 10 B-doped divaleryl diboron is not a commercially available compound, this method requires additional pretreatment of the preparation of the borating agent, resulting in a high process complexity and a long time consuming process. It is impossible to prepare a high yield of L-BPA. In addition, the carboxylic acid group of the protected (S)-4-iodophenylalanine at the amine end needs to be protected by a substituent to form a benzyl ester group to increase the process yield to 88%; however, The preparation of L-BPA in this manner also requires an additional step of deprotecting the carboxylic acid group, which in turn increases the process complexity of L-BPA.

Accordingly, the method provided in this document not only involves pre-treatment of the preparation of the borating agent, but also requires a large amount of process time and synthesis steps to complete the steps of protecting and deprotecting the carboxylic acid group, and is not advantageous as an industry. The main method of synthesizing L-BPA.

On the other hand, a method for synthesizing L-BPA by forming a bond (b) is a coupling reaction of an amino acid with a boron-containing benzyl fragment or a boron-containing benzaldehyde fragment. To synthesize L-BPA. Biosci. Biotech. Biochem. 1996, 60, 683 discloses an enantioselective synthesis of L-BPA which gives the hands of a cyclic ethers of boronic acid and L-proline The chiral derivatives from L-valine are subjected to a coupling reaction to produce L-BPA. However, this method requires the formation of a cyclic ether compound of boric acid from 4-boronobenzylbromide, followed by a coupling reaction with a chiral derivative of L-proline, and in the latter stage. The amino acid undergoes an undesired racemization in the synthesis step, so that the method requires an enzymatic resolution step to reduce the yield to obtain L-BPA having a certain optical purity.

Accordingly, the method provided in the literature still includes the steps of pretreatment of the preparation of the borating agent and post-treatment of the enzymatic resolution, so that the process involved in the method is complicated and takes a long time, and cannot be obtained. High yield of L-BPA.

In addition, L- 10 BPA (4-( 10 B)borono-L-phenylalanine, 4-( 10 B)dihydroxyboryl-L-phenylalanine) containing 10 boron is currently known to accumulate in tumor cells. The key factor is to use the thermal neutron beam to irradiate the boron element accumulated in the tumor cells to kill the tumor cells by capturing the high-energy particles generated by the reaction, thereby achieving the purpose of treating cancer. Therefore, 10 boron can promote the treatment of L- 10 BPA by boron neutron capture treatment.

However, the boron element present in nature contains about 19.9% of 10 boron and about 80.1% of 11 boron. Therefore, many researchers are still actively developing methods that can be applied to the synthesis of L-BPA, especially for the synthesis of 10- boron-rich L-BPA.

J.Org.Chem.1998,63,8019 additionally provides a method of synthesizing 10 boronated agents, since the method involves multiple steps, it is easy to greatly reduce the boron content of 10 10 boron enriched material in the manufacturing process. Therefore, the method provided in this document is not suitable for the synthesis of 10- boron-rich L-BPA.

Another example is the Biosci.Biotech.Biochem.1996,60,683, before the enzymatic resolution step is not performed, the method provided by the articles could not be obtained with a certain L-BPA optical purity; 10 and the method for preparing boronated agents when also relates to multi-step, resulting in conversion of boron-rich material 10 occurs during the manufacturing process. Therefore, the method provided in this document is also not suitable for the synthesis of 10- boron-rich L-BPA.

Furthermore, Bull. Chem. Soc. Jpn. 2000, 73, 231 discloses the use of palladium to catalyze 4-iodo-L-phenylalanine with 4,4,5,5-tetramethyl-1,3,2 A method in which a dioxonium pentoxide (common name: pinacolborane) is subjected to a coupling reaction. However, this document does not mention how to prepare articles 10 boron enriched L-BPA using this method, and 4,4,5,5-tetramethyl-1,3,2-dioxaborolane not a commercial 10 The compounds available in the literature are not suitable for the synthesis of 10- boron-rich L-BPA.

In addition, Synlett. 1996, 167 discloses a method for coupling a iodophenylborate with a zinc derivative of L-serine zinc derivatives, which involves first preparing phenyl iodoborate. The ester and the preparation of a zinc derivative of L-type serine acid, etc., result in a lower yield of the produced L-BPA. In addition, since the 10- boron-rich triiodide 10 boron and 1,3-diphenylpropane-1,3-diol selected for this method are not commercially available compounds, the methods provided in this document are also provided. Still not suitable for the synthesis of 10- boron-rich L-BPA.

SYN

Repub. Korean Kongkae Taeho Kongbo, 2018060319,

PAPER

Research and Development in Neutron Capture Therapy, Proceedings of the International Congress on Neutron Capture Therapy, 10th, Essen, Germany, Sept. 8-13, 2002 (2002), 1-8.

PAPER

European Journal of Pharmaceutical Sciences (2003), 18(2), 155-163

https://www.sciencedirect.com/science/article/abs/pii/S0928098702002567

Clinical implementation of 4-dihydroxyborylphenylalanine synthesised by an asymmetric pathway - ScienceDirect
Clinical implementation of 4-dihydroxyborylphenylalanine synthesised by an asymmetric pathway - ScienceDirect

PAPER

Tetrahedron Letters (2008), 49(33), 4977-4980

PATENT

WO 2004009135

PATENT

US 20130331599

PATENT

WO 2017028751

https://patents.google.com/patent/WO2017028751A1/en

Example 1

Before preparing (S)-N-tert-butoxycarbonyl-4-dihydroxyborylphenylalanine from (S)-N-tert-butoxycarbonyl-4-iodophenylalanine, it is necessary to reveal Process for preparing (S)-N-tert-butoxycarbonyl-4-iodophenylalanine by using (S)-4-iodophenylalanine as a starting material and a process for preparing 10 tributyl borate with 10 boric acid.

1. Preparation of (S)-N-tert-butoxycarbonyl-4-iodophenylalanine from (S)-4-iodophenylalanine

Please refer to the following reaction formula I, which is (S)-4-iodophenylalanine in a solvent of 1,4-dioxane (1,4-dioxane) and water (H 2 O) with hydrogen peroxide. Sodium (NaOH) and di-tert-butyl dicarbonate (Boc 2 O) are reacted to obtain a chemical reaction formula of (S)-N-tert-butoxycarbonyl-4-iodophenylalanine.

Figure PCTCN2016094881-appb-000005

In the preparation process, two reaction vessels were selected for the reaction.

The specific operation process is as follows:

1. Set up a reaction using a 3L three-neck bottle.

2. (S)-4-iodo-L-phenylalanine (200.00 g, 687.10 mmol, 1.00 eq) was added to the reaction system.

3. Add 1,4-dioxane (1.00 L) and water (1.00 L) to the reaction system, respectively.

4. Sodium hydroxide (68.71 g, 1.72 mol, 2.50 eq) was added to the reaction system, the solution gradually became clear, and the temperature rose slightly to 19 °C.

5. When the system is cooled to 0-10 ° C, di-tert-butyl dicarbonate (254.93 g, 1.17 mol, 268.35 mL, 1.70 eq) is added to the reaction system, and the temperature of the reaction system is naturally raised to 10 to 30 ° C and Stir at room temperature (about 30 ° C) for 8 hours.

6. The reaction was detected using high performance liquid chromatography (HPLC) until the starting of the reaction.

7. The temperature of the control system is less than 40 ° C, and the 1,4-dioxane in the reaction solution is concentrated.

8. The reaction system was lowered to room temperature (about 25 ° C), 100 mL of water was added, and the pH was adjusted to 1.8-2 with hydrochloric acid (2M (ie, molarity, M)).

9. Extract three times with ethyl acetate (2 L).

10. Combine the organic phases and wash twice with saturated brine (1 L).

11. The organic phase was dried over sodium sulfate (200 g).

12. Continue drying in an oven (40-45 ° C) to give (S)-N-tert-butoxycarbonyl-4-iodo-L-phenylalanine (250.00 g, 626.28 mmol, HPLC analysis, yield 93.00 %, purity 98%).

The prepared (S) -N- tert-butoxycarbonyl-4-iodo-phenylalanine was -L- Hydrogen 1 nuclear magnetic resonance spectrum analysis (1 HNMR) as follows:

1 H NMR: (400 MHz DMSO-d 6 )

δ 7.49 (d, J = 7.8 Hz, 2H), 6.88 (d, J = 7.8 Hz, 2H), 5.80 (d, J = 5.9 Hz, 1H), 3.68 (d, J = 5.5 Hz, 1H), 3.00-2.90 (m, 1H), 2.87-2.75 (m, 1H), 1.35-1.15 (m, 9H).

Second, tributyl borate 10 was prepared from boronic acid 10

See the following reaction formulas II, 10 as boric acid (H 2 SO 4) is reacted with sulfuric acid in a solvent (butan-1-ol), and toluene (Toluene) in n-butanol, to obtain 10 tributyl borate (10 The chemical reaction formula of B(OBu) 3 ).

Figure PCTCN2016094881-appb-000006

The specific operation process is as follows:

1. Set up a reaction device R1 using a 3L three-necked bottle, and configure a water separator on the device.

2. 10 boric acid (150.00 g, 2.46 mol, 1.00 eq) was added to the reaction R1 at room temperature (about 25 ° C).

3. Add n-butanol (1.00 L) to the reaction R1 at room temperature (about 25 ° C) and stir, and most of the boric acid cannot be dissolved.

4. Toluene (1.00 L) was added to the reaction R1 at room temperature (about 25 ° C) and stirred.

5. Concentrated sulfuric acid (4.82 g, 49.16 mmol, 2.62 mL, 0.02 eq) was added dropwise to the reaction at room temperature (about 25 ° C), at which time a large amount of solid remained undissolved.

6. The reaction system was heated to 130 ° C, and the water was continuously removed, stirred for 3.5 hours, and water (about 140 g) was formed in the water separator. The solids were all dissolved, and the solution changed from colorless to brown. .

7. TLC (DCM: MeOH = 5:1, Rf = 0.43, bromocresol green).

8. Distill off most of the toluene at atmospheric pressure.

9. After most of the toluene is distilled off, the temperature of the system is lowered to 20 to 30 ° C, and the reaction liquids of the two reactions are combined, and the apparatus is changed for distillation.

10. Oil bath external temperature 108-110 ° C pump distillation under reduced pressure, Kelvin thermometer 45 ° C, distilled n-butanol.

11. Oil bath external temperature 108-110 ° C oil pump distillation under reduced pressure, the residual butanol was distilled off.

12. Oil bath external temperature 118-120 ° C oil pump vacuum distillation, Kelvin thermometer 55 ° C, began to produce products.

13. The temperature is raised to 135-140 ° C oil pump vacuum distillation, the product is completely distilled.

14. The product is obtained as a colorless liquid 10 tributyl borate (830.00g, 3.62mol, yield 73.58%).

The results of the 1 H NMR analysis of the obtained tributyl 10 borate were as follows:

1 H NMR: (400 MHz CDCl 3 )

δ 3.82-3.68 (m, 6H), 1.57-1.42 (m, 6H), 1.34 (qd, J = 7.4, 14.9 Hz, 6H), 0.95-0.80 (m, 9H).

Three, -N- tert-butoxycarbonyl-4-iodo-phenylalanine was prepared (S) of (S) -N- tert-butoxycarbonyl-4-hydroxy-10-yl -L- phenylalanine boron

Please refer to the following reaction formula III, which is (S)-N-tert-butoxycarbonyl-4-iodophenylalanine with tributyl 10 borate, t-butyl magnesium chloride (t-BuMgCl) and bis (2-A) yl aminoethyl) ether (BDMAEE) reaction, to produce (S) -N- tert-butoxycarbonyl group -4- (10 B) dihydroxyboryl -L- phenylalanine chemical reaction.

Figure PCTCN2016094881-appb-000007

In the preparation process, two reaction vessels were selected for the reaction.

The specific operation process is as follows:

1. Set up a reaction using a 3L three-neck bottle.

2. Tributyl 10 borate (187.60 g, 87.98 mmol, 3.20 eq) was placed in the reaction system at room temperature (about 22 ° C).

3. Sodium hydride (20.45 g, 511.24 mmol, purity 60%, 2.00 eq) was added to the reaction system at room temperature (about 22 ° C). The reaction solution was a suspension and stirred at room temperature (about 22 ° C). 5 minutes.

4. Bis(2-methylaminoethyl)ether (327.73 g, 2.04 mol, 8.00 eq) was added to the reaction at room temperature (about 22 ° C).

5. N-tert-Butoxycarbonyl-4-iodo-L-phenylalanine (100.00 g, 255.62 mmol, 1.00 eq) was added to the reaction system at room temperature (about 22 ° C), and a large amount of solid was not dissolved.

6. Lower the temperature of the reaction system to 0-5 ° C, add t-butyl magnesium chloride (1.7 M, 1.20 L, 2.04 mol, 8.00 eq) to the reaction, control the temperature between 0-10 ° C, the dropping time is about It is 1.5 hours.

7. After the completion of the charging, the temperature of the reaction system was naturally raised to room temperature (20 to 30 ° C) and stirred at this temperature for 12 hours.

8. Using high performance liquid chromatography (HPLC) to detect about 9.00% of the remaining material.

9. When the temperature of the reaction system was lowered to -5 to 0 ° C, it was quenched by dropwise addition of 500 mL of water.

10. Lower the temperature of the system to 0-5 ° C, add methyl tert-butyl ether (500 mL) to the reaction system and adjust the pH to 2.9-3.1 (using a pH meter) with 37% HCl (about 500 mL). Exothermic, the temperature of the control system is between 0-15 °C.

11. The aqueous phase obtained by liquid separation was extracted once with methyl tert-butyl ether (500 mL), and the obtained organic phases were combined to give an organic phase of about 1.1 L.

12. Slowly add a sodium hydroxide aqueous solution (1 M, 400 mL) to the obtained organic phase, exotherm during the dropwise addition, and control the system temperature between 0-15 °C.

13. After the completion of the dropwise addition, the pH of the system was about 10, and the pH was adjusted to between 12.10 and 12.6 with an aqueous sodium hydroxide solution (4M). (measured with a pH meter)

14. Dispensing.

15. The aqueous phase 1 obtained after liquid separation was extracted once with n-butanol (500 ml) to obtain aqueous phase 2.

16. Combine the aqueous phase 2 of the two reaction vessels.

17. Adjust the pH of the aqueous phase to 2.9-3.1 with 37% HCl, stir for about 40 minutes, and precipitate a large amount of solid.

18. Filtration gave a white solid which was washed once with dichloromethane (50 mL).

19. At 25 ° C, the precipitated solid was slurried with dichloromethane (150 mL) and stirred for 10 min.

20. A white solid was filtered to give (S) -N- tert-butoxycarbonyl group -4- (10 B) dihydroxyboryl -L- phenylalanine (75.00g, 240.82mmol, by HPLC analysis, a yield of 47.11% , purity 99%).

The prepared (S) -N- tert-butoxycarbonyl group -4- (10 B) results dihydroxyboryl -L- phenylalanine 1 HNMR was as follows:

1 H NMR: (400 MHz DMSO-d 6 )

Δ12.55 (br.s., 1H), 7.91 (s, 2H), 7.66 (d, J = 7.5 Hz, 2H), 7.17 (d, J = 7.5 Hz, 2H), 4.08-4.01 (m, 1H) ), 3.61-3.53 (m, 1H), 2.98 (dd, J = 4.2, 13.9 Hz, 1H), 2.79 (dd, J = 10.4, 13.5 Hz, 1H), 1.79-1.67 (m, 1H), 1.35- 1.17 (m, 9H).

Preparation of L- 10 BPA from (S)-N-tert-Butoxycarbonyl-4-dihydroxyboryl-L-phenylalanine

See the following reaction scheme IV, which is (S) -N- tert-butoxycarbonyl group -4- (10 B) of amine end dihydroxyboryl -L- phenylalanine deprotection of the chemical reaction, to obtain L- 10 BPA.

Figure PCTCN2016094881-appb-000008

The specific operation process is as follows:

1. Set up a reaction using a 1L three-neck bottle.

2. room temperature (20-30 deg.] C) to (S) -N- tert-butoxycarbonyl group -4- (10 B) dihydroxyboryl -L- phenylalanine (67.00g, 217.31mmol, 1.00eq) was added the reaction In the system.

3. room temperature (20-30 deg.] C) water (23.75mL) and acetone (Acetone, 420.00mL) were added dropwise to the reaction flask, stirred (S) -N- tert-butoxycarbonyl group -4- (10 B) dihydroxy Boronyl-L-phenylalanine.

4. Concentrated hydrochloric acid (23.93 g, 656.28 mmol, 23.46 mL, 3.02 eq) was added dropwise to the reaction system at room temperature (20-30 ° C). After the addition was completed, the reaction system was heated to 55-60 ° C and stirred for 4.5 hours.

5. HPLC detection until the reaction of the starting material is completed.

6. The temperature is controlled below 40 ° C, and the acetone in the reaction system is concentrated.

7. Lower the concentrated system to below 15 °C, adjust the pH of the system to about 1.5 with sodium hydroxide solution (4M) (pH meter detection), stir for 40 minutes and continue to adjust the pH of the system to 6.15 using sodium hydroxide solution (4M). ~6.25, a large amount of white solid precipitated, which was filtered to give a white solid, and rinsed with acetone (200mL).

8. Obtained as a white solid L- 10 BPA (36.00 g, 171.17 mmol, HPLC, yield 78.77%, purity 99%).

The analytical results obtained by the L- 10 BPA 1 HNMR are as follows:

1 H NMR: (400 MHz D 2 O, CF 3 COOH)

δ 7.44 (d, J = 7.9 Hz, 1H), 7.03 (d, J = 7.9 Hz, 1H), 4.06 (dd, J = 5.7, 7.5 Hz, 1H), 3.11-3.01 (m, 1H), 2.98 -2.87 (m, 1H).

xample 6

Preparation of (S)-N-tert-butoxycarbonyl-4-dihydroxyboryl-L-phenylalanine from (S)-N-tert-butoxycarbonyl-4-iodophenylalanine

Please refer to the following reaction formula VII, which is a reaction of (S)-N-tert-butoxycarbonyl-4-iodophenylalanine with tributyl borate and t-butylmagnesium chloride (t-BuMgCl) to obtain (S The chemical reaction formula of -N-tert-butoxycarbonyl-4-dihydroxyboryl-L-phenylalanine.

Figure PCTCN2016094881-appb-000013

The specific operation process is as follows:

1. Construct a reaction unit with a 250 mL three-neck bottle.

2. Tributyl borate (17.65 g, 76.68 mmol, 3.00 eq) was placed in a 250 mL reaction flask at 20-30 °C.

3. Sodium hydride (1.02 g, 25.56 mmol, 1.00 eq) was added to a 250 mL reaction vial at 20-30 °C.

4. (S)-N-tert-Butoxycarbonyl-4-iodo-L-phenylalanine (10.00 g, 25.56 mmol, 1.00 eq) was added to a 250 mL reaction vial at 20-30 °C.

5. Reduce the temperature of the reaction system to 0 ° C under nitrogen atmosphere, slowly add t-butyl magnesium chloride (1.7 M in THF, 120 mL, 8.00 eq) to the reaction, the dropping time is about 30 minutes, and the control temperature is 0. Between °C and 10 °C.

Stir at 20.20 ~ 30 ° C for 20 hours.

7. HPLC detection of the basic reaction of the raw materials, leaving only about 0.7% of the raw materials.

8. At a temperature of 0 ° C, 5 mL of water was added dropwise to the reaction to quench it. After complete quenching, stirring was continued for 10 minutes.

9. Cool down to 0 ° C, add methyl tert-butyl ether (50 mL) to the reaction and adjust the pH to 3 with 37% HCl (about 50 mL) (detected with a pH meter), adjust the pH during the process to exotherm, control the temperature at 0 Between °C and 15 °C.

12. The aqueous phase obtained by liquid separation was extracted once with methyl t-butyl ether (50 mL) and the organic phases were combined.

12. Add NaOH solution (1M, 55mL) to the obtained organic phase to adjust the pH to between 12.10-12.6. The process is exothermic and the temperature is controlled between 0 °C and 15 °C.

13. Liquid separation, the obtained aqueous phase was extracted once with n-butanol (50 mL), and most of the impurities were extracted and removed.

14. The aqueous phase obtained by liquid separation was adjusted to pH 3 with 37% HCl and stirred for about 30 minutes to precipitate a white solid.

15. Filtration gave a white solid which was washed once with dichloromethane (50 mL).

16. The precipitated solid was slurried with 25 mL of dichloromethane at 25 ° C and stirred for 10 minutes.

17. Filtration of (S)-N-tert-butoxycarbonyl-4-dihydroxyboryl-L-phenylalanine (6.8 g, HPLC, yield: 83.15%, purity 98%).

Example 7

Please continue to refer to Reaction Scheme VII. The specific operation process is as follows:

1. Construct a reaction unit with a 250 mL three-neck bottle.

2. Tributyl borate (8.82 g, 38.34 mmol, 3.00 eq) was added to a 250 mL reaction vial at 20-30 °C.

3. Sodium hydride (511.25 mg, 12.78 mmol, 1.00 eq) was added to a 250 mL reaction vial at 20-30 °C.

4. (S)-N-tert-Butoxycarbonyl-4-iodo-L-phenylalanine (5.00 g, 12.78 mmol, 1.00 eq) was added to a 250 mL reaction vial at 20-30 °C.

5. The temperature of the reaction system was lowered to 0 ° C under nitrogen atmosphere, and t-butyl magnesium chloride (1.7 M in THF, 60 mL, 8.00 eq) was added dropwise to the reaction, the dropwise addition time was about 30 minutes, and the control temperature was 0 ° C. -10 ° C between.

Stir at 6.20 ~ 30 ° C for 22 hours.

7. HPLC detection of the raw material reaction is completed.

8. At a temperature of 0 ° C, 2.5 mL of water was added dropwise to the reaction to quench it. After complete quenching, stirring was continued for 10 minutes.

9. Cool down to 0 ° C, add methyl tert-butyl ether (25 mL) to the reaction and adjust the pH to 3 with 37% HCl (about 25 mL) (detected with a pH meter), adjust the pH during the process to exotherm, control the temperature at 0 Between °C and 15 °C.

12. The aqueous phase obtained by liquid separation was extracted once with methyl t-butyl ether (25 mL) and the organic phases were combined.

12. Add NaOH solution (1M, 30mL) to the obtained organic phase to adjust the pH to between 12.10-12.6. The process is exothermic and the temperature is controlled between 0 °C and 15 °C.

13. Liquid separation, the obtained aqueous phase was extracted once with n-butanol (25 ml), and most of the impurities were extracted and removed.

14. The aqueous phase obtained by liquid separation was adjusted to pH 3 with 37% HCl and stirred for about 30 minutes to precipitate a white solid.

15. Filtration gave a white solid which was washed once with dichloromethane (25 mL).

16. The precipitated solid was slurried with 15 mL of dichloromethane at 25 ° C and stirred for 10 minutes.

17. Filtration gave (S)-N-tert-butoxycarbonyl-4-dihydroxyboryl-L-phenylalanine (3.4 g, obtained by HPLC, yield: 85.26%, purity 98%).

Bis(2-methylaminoethyl)ether is a complexing agent for Mg, which can reduce the occurrence of side reactions in the reaction. The reactions of Examples 6 and 7 were carried out without adding bis(2-methylaminoethyl)ether. The analysis showed that the iodine impurity in the reaction of Example 6 was about 17%, and the iodine impurity in the reaction of Example 7 was observed. About 28%. Therefore, it has been proved from the side that the addition of bis(2-methylaminoethyl)ether can protect the reaction from reducing iodine.

The BPA or 10 BPA obtained in the above examples were analyzed by chiral HPLC, and the ratio of the L-enantiomer to the D-enantiomer was 100:0.

The boron-containing drug L-BPA for neutron capture therapy disclosed in the present invention is not limited to the contents described in the above examples. The above-mentioned embodiments are only examples for convenience of description, and the scope of the claims should be determined by the claims.

PATENT

KR 2018060319

PATENT

WO 2019163790

https://patentscope.wipo.int/search/en/detail.jsf?docId=WO2019163790

///////////Borofalan (10B), Borofalan, Steboronine, JAPAN 2020, 2020 APPROVALS, ボロファラン (10B), ボロファラン , 硼[10B]法仑 , 

B(C1=CC=C(C=C1)CC(C(=O)O)N)(O)O


Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.

DR ANTHONY CRASTO

Follow New Drug Approvals on WordPress.com

Enter your email address to follow this blog and receive notifications of new posts by email.

Join 2,653 other followers

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 LIFE SCIENCES 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 PLUS year tenure till date June 2021, 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, 90 Lakh plus views on dozen plus blogs, 233 countries, 7 continents, 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 33 lakh plus views on New Drug Approvals Blog in 233 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

Personal Links

View Full Profile →

TWITTER

bloglovin

Follow my blog with Bloglovin The title of your home page You could put your verification ID in a comment Or, in its own meta tag Or, as one of your keywords Your content is here. The verification ID will NOT be detected if you put it here.
%d bloggers like this: