Davelizomib

Molecular Weight	481.25
Formula	C21H26BF2N3O7
CAS No.	2409841-51-4

{(4S)-2-[(1R)-1-{2-[(2S)-1-(2,4-difluorophenyl)azetidine-2- carboxamido]acetamido}-3-methylbutyl]-5-oxo-1,3,2- dioxaborolan-4-yl}acetic acid proteasome inhibitor, antineoplastic

2-[(4S)-2-[(1R)-1-[[2-[[(2S)-1-(2,4-difluorophenyl)azetidine-2-carbonyl]amino]acetyl]amino]-3-methylbutyl]-5-oxo-1,3,2-dioxaborolan-4-yl]acetic acid

• 1,3,2-Dioxaborolane-4-acetic acid, 2-[(1R)-1-[[2-[[[(2S)-1-(2,4-difluorophenyl)-2-azetidinyl]carbonyl]amino]acetyl]amino]-3-methylbutyl]-5-oxo-, (4S)-
• 2-[(4S)-2-[(1R)-1-[[2-[[(2S)-1-(2,4-difluorophenyl)azetidine-2-carbonyl]amino]acetyl]amino]-3-methylbutyl]-5-oxo-1,3,2-dioxaborolan-4-yl]acetic acid

T3LN9U6BRF

Davelizomib is proteasome inhibitor with antineoplastic effect.

DAVELIZOMIB is a small molecule drug with a maximum clinical trial phase of II and has 1 investigational indication.

Multiple myeloma (MM) is a malignant proliferative disease of plasma cells, characterized by abnormal proliferation of clonal plasma cells in the bone marrow, destruction of hematopoietic function, stimulation of osteolytic lesions in the bones, detection of monoclonal immunoglobulins or their fragments (M protein) in serum and/or urine, and clinical manifestations of bone pain, anemia, hypercalcemia, renal impairment, infection, and bleeding. Bortezomib is a reversible proteasome inhibitor that achieves the purpose of treating multiple myeloma by promoting apoptosis of myeloma cells. However, in the long-term treatment process, some multiple myeloma patients have developed resistance to bortezomib. Therefore, there is still a need for new, safe, and highly stable drugs for the treatment of multiple myeloma.

SCHEME

PATENT

Borate of azetidine derivative

Publication Number: JP-2021531302-A

Priority Date: 2018-08-02

WO2020025037

Step 1: Synthesis of compound 4-3 

[0252]N, N-diisopropylethylamine (22.02 g) was added to a solution of acetonitrile (200 mL) containing compound 4-1 (10 g) and compound 4-2 (20.13 g) at room temperature. The reaction mixture was stirred at 100 ° C for 16 hours, then cooled to room temperature and then added to ethyl acetate. The organic layer was washed with water and saturated brine, respectively, and then the organic layer was dried over anhydrous sodium sulfate and filtered. The filtrate was concentrated to remove the solvent, and the residue was purified by silica gel column chromatography (mobile phase: petroleum ether: ethyl acetate = 10: 1) to obtain compound 4-3. Compound 4-3: MS (ESI) m/z: 227.9 [M+1]. 

[0253]Step 2: Synthesis of compound 4-4 

[0254]

_{LiOH·H 2} O (6.65 g) was added to a mixed solution of compound 4-3 (7.2 g) in methanol (20 mL), tetrahydrofuran (20 mL) and water (10 mL) at 0°C. The reaction mixture was stirred at room temperature for 1 hour, then concentrated under reduced pressure, diluted with water and ethyl acetate, and separated. The aqueous layer was adjusted to pH=6 with 1 mol/L hydrochloric acid, and then extracted with ethyl acetate. The organic phases were combined and washed with saturated brine, dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated to remove the solvent to obtain compound 4-4, which was directly used in the next step. Compound 4-4: MS (ESI) m/z: 213.9 [M+1]. 

[0255]Step 3: Synthesis of compound 4-5 

[0256]Glycine methyl ester hydrochloride (1.06 g), TBTU (2.71 g) and N,N-diisopropylethylamine (3.64 g) were added to a solution of compound 4-4 (1.5 g) in dichloromethane (50 mL) at -10°C. The reaction mixture was stirred at -10°C to 0°C for 3 hours, then diluted with water (40 mL) and extracted with dichloromethane. The organic phases were combined, washed with saturated brine, dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated to remove the solvent, and the residue was purified by silica gel column chromatography (mobile phase: petroleum ether: ethyl acetate = 5:1) to obtain compound 4-5. Compound 4-5: MS (ESI) m/z: 284.9 [M+1]. 

[0257]Step 4: Synthesis of Compound 4-6 

[0258]To a mixed solution of compound 4-5 (0.5 g) in tetrahydrofuran (2 mL), methanol (2 mL) and water (1 mL) was added LiOH·H 

₂ O (369.03 mg) at 0°C. The reaction mixture was stirred at 0°C to 20°C for 2 hours, then concentrated, diluted with water (3 mL), and separated. The aqueous layer was adjusted to pH=6 with 1 mol/L hydrochloric acid and extracted with ethyl acetate. The organic phases were combined, washed with saturated brine, dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated to remove the solvent to obtain compound 4-6, which was directly used in the next step. Compound 4-6: MS (ESI) m/z: 270.9 [M+1]. 

[0259]Step 5: Synthesis of Compound 4-8 

[0260]N,N-diisopropylethylamine (273.56 mg) was added to a solution of compound 4-6 (0.26 g), compound 2-6 (437.84 mg) and TBTU (370.71 mg) in dichloromethane (10 mL) at -10 ° C. The reaction mixture was slowly warmed to room temperature and continued to stir for 2 hours, then the reaction mixture was added to water (10 mL) for dilution and extracted with dichloromethane. The organic phases were combined, washed with saturated brine, dried over anhydrous sodium sulfate, and filtered. The filtrate was concentrated to remove the solvent, and the residue was purified by silica gel column chromatography (mobile phase: petroleum ether: ethyl acetate = 1: 1) to obtain compound 4-8. Compound 4-8: MS (ESI) m/z: 518.2 [M+1]. 

[0261]Step 6: Synthesis of Compound 4-9 

[0262]Isobutylboric acid (234.45 mg) and 1 mol/L HCl (1.31 mL) were added to a mixed solution of methanol (4 mL) and n-hexane (6 mL) of compound 4-8 (0.17 g) at 0°C. The reaction mixture was slowly warmed to room temperature and stirred for 12 hours, then concentrated under reduced pressure to remove the solvent to obtain a residue. The residue was purified by preparative HPLC and separated by SFC to obtain compound 4-9. Compound 4-9: 

¹ H NMR (400MHz, METHANOL-d4) δ6.83(br s,2H),6.61(br s,1H),4.49(br s,1H),4.10(br s,3H),3.84(br s,1H),2.75(br s,1H),2.59(br s,1H),2.48(br s,1H),1.62(br s,1H),1.30(br s,2H),0.92(br s,6H). MS(ESI)m/z:366.1[M-17]. 

[0263]Preparative HPLC separation method of compound 4-9: 

[0264]Column: Xtimate C18 150×25mm, 5μm; 

[0265]Mobile phase: water (0.225% FA)-MeOH; 

[0266]Elution gradient: 61%-85%; 

[0267]Retention time: 9.5min. 

[0268]Preparation of compound 4-9 SFC separation method: 

[0269]Chromatographic column: C2 250mm×30mm, 10μm; 

[0270]Mobile phase: A: carbon dioxide, B: methanol; 

[0271]Elution gradient B%: 30%-30%; 

[0272]Flow rate: 60mL/min. 

[0273]The elution order of compound 4-9 is the second peak appearing in high performance chiral liquid column chromatography. 

[0274]Step 7: Synthesis of Compound I-1 

[0275]Method 1: Add L-malic acid (332 mg) to isopropyl acetate (2.5 mL), heat to 70°C and stir, and after 10 minutes, add compound 4-9 (1.0 g) dissolved in 2.5 mL isopropyl acetate solution. Then stop heating, cool to 25°C and continue stirring at this temperature for 5 days. Filter, collect the filter cake, and vacuum dry to obtain compound I-1, which is Form I crystal of compound I-1. 

[0276]Method 2: Add compound I-1 (68.9 g) to a reaction flask, then add 440 mL of isopropyl acetate, and stir the mixture at room temperature for 24 h under nitrogen protection. Filter and dry to obtain Form I crystals of compound I-1 (64.4 g). The X-ray powder diffraction pattern of the obtained crystals using Cu Kα rays is shown in Figure 1. 

[0277]

化合物I-1： ¹H NMR(400MHz,DMSO-d ₆)δ12.30(br s,1H),10.65(br s,1H),8.57(br t,J＝5.77Hz,1H),7.11(ddd,J＝2.64,9.16,12.30Hz,1H),6.91(br t,J＝8.16Hz,1H),6.53(dt,J＝5.65,9.60Hz,1H),4.44(br t,J＝7.91Hz,1H),4.37(dd,J＝3.89,7.65Hz,1H),4.10(br s,2H),3.91-4.01(m,1H),3.76(q,J＝7.36Hz,1H),2.61(br d,J＝10.79Hz,2H),2.19-2.44(m,3H),1.61(td,J＝6.71,13.68Hz,1H),1.20-1.36(m,2H),0.86(t,J＝6.02Hz,6H)。

[1]. Xiong, et al. Preparation and medicinal application of borates of azetidine derivatives. World Intellectual Property Organization, WO2020025037 A1. 2020-02-06.

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