BOFUTRELVIR

Cas 2103278-86-8

Molecular Weight	452.55
Formula	C25H32N4O4

UNII-T5UX5SKK2S; Mpro inhibitor 11A; 2103278-86-8; T5UX5SKK2S, DC-402234, DC402234, MPI-10

IUPAC/Chemical Name: N-[(2S)-3-cyclohexyl-1-oxo-1-[[(2S)-1-oxo-3-[(3S)-2-oxopyrrolidin-3-yl]propan-2-yl]amino]propan-2-yl]-1H-indole-2-carboxamide

N-[(2S)-3-cyclohexyl-1-oxo-1-[[(2S)-1-oxo-3-[(3S)-2-oxopyrrolidin-3-yl]propan-2-yl]amino]propan-2-yl]-1H-indole-2-carboxamide

Bofutrelvir has an additive antiviral effect when combined with Remdesivir 

FB2001

Bofutrelvir (FB2001) is a SARS-CoV-2 main protease M^pro inhibitor with an IC₅₀ value of 53 nM and an EC₅₀ value of 0.53 μM. Bofutrelvir exhibits potent antiviral efficacy against several current SARS-CoV-2 variants with EC₅₀ values of 0.26-0.42 μM. Bofutrelvir has an additive antiviral effect when combined with Remdesivir.

Bofutrelvir is a small molecule inhibitor of the severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) main protease (Mpro; 3C-like protease; 3CL protease; 3CLpro; nsp5 protease), with potential antiviral activity against SARS-CoV-2. Upon intravenous administration or inhalation into the lungs, bofutrelvir selectively targets, binds to, and inhibits the activity of SARS-CoV-2 Mpro. This inhibits the proteolytic cleavage of viral polyproteins, thereby inhibiting the formation of viral proteins including helicase, single-stranded-RNA-binding protein, RNA-dependent RNA polymerase, 20-O-ribose methyltransferase, endoribonuclease and exoribonuclease. This prevents viral transcription and replication. Bofutrelvir may have antiviral activity in the brain.

• Originator Frontier Biotechnologies
• Class Amides; Antivirals; Indoles; Pyrrolidinones; Small molecules
• Mechanism of Action Coronavirus 3C-like proteinase inhibitors

Highest Development Phases

• Phase II/III COVID 2019 infections

Most Recent Events

• 28 Apr 2024No recent reports of development identified for phase-I development in COVID-2019-infections in USA (IV, Infusion)
• 04 Jan 2023Phase-II/III clinical trials in COVID-2019 infections in China (Inhalation) (NCT05675072)
• 30 Dec 2022Frontier Biotechnologies completes a phase I trial in COVID-2019 infections in China (Inhalation) (NCT05583812)
• N-[(2S)-3-cyclohexyl-1-oxo-1-({(2S)-1-oxo-3-[(3S)-2-oxopyrrolidin-3-yl]propan-2-yl}amino)propan-2-yl]-1H-indole-2-carboxamide is a secondary carboxamide resulting from the formal condensation of the carboxy group of 1H-indole-2-carboxylic acid with the primary amino group of 3-cyclohexyl-N-{(2S)-1-oxo-3-[(3S)-2-oxopyrrolidin-3-yl]propan-2-yl}-L-alaninamide. It is an inhibitor of SARS coronavirus main proteinase and inhibits SARS-CoV-2 replication in cell culture (EC50 = 0.53 muM). It has a role as an EC 3.4.22.69 (SARS coronavirus main proteinase) inhibitor and an anticoronaviral agent. It is an indolecarboxamide, a member of pyrrolidin-2-ones, an aldehyde, a secondary carboxamide and an oligopeptide.

SCHEME

PATENTS

CN110818691

https://patentscope.wipo.int/search/en/detail.jsf?docId=CN289596961&_cid=P11-M9Z1Y3-09353-1

Synthesis of compound 1-2:

Under argon protection, N-tert-butyloxycarbonyl-L-glutamic acid dimethyl ester (1-1) (6g, 21.8mmol) was dissolved in 60mL of anhydrous tetrahydrofuran, and a tetrahydrofuran solution of LiHMDS (1M in THF) (47mL, 47mmol) was slowly dripped at -78℃, and the temperature was kept stable at -78℃ during the dripping process, which lasted for about 1 hour. After the dripping was completed, it was stirred at -78℃ for 1 hour. Bromoacetonitrile (2.79g, 23.3mmol) was dissolved in 20ml of tetrahydrofuran, and then the solution was slowly dripped into the reaction system, and the dripping process lasted for 1 to 2 hours. The temperature was controlled at -78℃ and the reaction was continued for 3 hours. After the reaction was completed, NH4Cl solution was added to the reaction solution to quench the reaction, and the mixture was stirred for 10min and then warmed to room temperature. 40mL of saturated sodium chloride solution was poured in and stirred thoroughly, and the reaction system was seen to be stratified. The organic layer was separated, and the aqueous phase was extracted with ethyl acetate (EA). The organic layers were combined, dried over anhydrous sodium sulfate, concentrated, and subjected to column chromatography (Flash, PE:EA=1:5) to obtain 3.9 g of a light yellow oil 1-2 with a yield of 58%.

Synthesis of compound 1-3:

Dissolve 1-2 (1 g, 3.15 mmol) in 25 mL of anhydrous methanol, stir to 0°C in an ice bath, and then add cobalt dichloride hexahydrate (450 mg, 1.89 mmol). After 10 min, add sodium borohydride (715 mg, 18.9 mmol) in small portions. The reaction solution continues to react in an ice bath for 1 h and then returns to room temperature. After 15 h, quench with 5 mL of saturated NH4Cl solution and continue stirring for 10 min. After filtering out the solid, evaporate the filtrate to dryness, extract with 20 mL of water and 30×3 mL of ethyl acetate, combine the organic phases, and add anhydrous Na 2 SO 4 After drying for 1 h, the residue was concentrated under reduced pressure and separated by column chromatography [PE:EA=1:2] to obtain 460 mg of a white powdery solid with a yield of 51%.

Synthesis of compound 1-4:

Compound 1-3 (2.6 g) was dissolved in a dichloromethane solution of trifluoroacetic acid (1/1, v/v), stirred at room temperature for 1 hour, concentrated, added with 100 ml of dichloromethane, washed with saturated sodium carbonate solution, and the organic layer was dried over anhydrous sodium sulfate and concentrated to obtain an oily substance 1-4 (2.7 g) with a yield of 99%.

Synthesis of compound 1-5:

Boc-cyclohexylalanine (1.26 g, 5 mmol), EDCI (1.36 g, 6 mmol), and HOBt (0.822 g, 6 mmol) were added to 80 ml of dichloromethane solution and stirred at room temperature for 30 min. Compound 1-4 (0.896 g, 5 mmol) was then added, and 1.2 equivalents of triethylamine were added dropwise, and stirred at room temperature. After TLC monitoring (ultraviolet), dichloromethane was used for extraction after the reaction was complete, and the mixture was washed with dilute hydrochloric acid, saturated sodium bicarbonate solution, and saturated sodium chloride. The organic layers were combined and dried over anhydrous sodium sulfate, and concentrated to obtain 1.2 g of a white viscous solid with a yield of 60%.

Synthesis of compound 1-6:

Compound 1-5 (2.5 g) was dissolved in a dichloromethane solution of trifluoroacetic acid (1/1, v/v), stirred at room temperature for 1 hour, concentrated, added with 100 ml of dichloromethane, washed with saturated sodium carbonate solution, and the organic layer was dried over anhydrous sodium sulfate and concentrated to obtain an oily substance 1-6 (2.61 g) with a yield of 99%.

Synthesis of compound 1-7:

Indole 2-carboxylic acid (0.795 g, 5 mmol), EDCI (1.36 g, 6 mmol), and HOBt (0.822 g, 6 mmol) were added to 80 ml of dichloromethane solution and stirred at room temperature for 30 min. Compound 1-6 (2.2 g, 5 mmol) was then added, and 1.2 equivalents of triethylamine were added dropwise, and stirred at room temperature. After TLC monitoring (ultraviolet), dichloromethane was used for extraction after the reaction was complete, and the mixture was washed with dilute hydrochloric acid, saturated sodium bicarbonate solution, and saturated sodium chloride. The organic layers were combined and dried over anhydrous sodium sulfate, and concentrated to obtain 1.3 g of a white viscous solid with a yield of 60%.

Synthesis of compound 1-8:

Dissolve 1-7 (243 mg, 0.51 mmol) in 20 ml of methanol, slowly add sodium borohydride (107 mg, 2.9 mmol) in batches, and stir at room temperature for about 2 hours to complete the reaction. After the reaction is completed, add about 20 ml of saturated brine to quench the reaction, concentrate the methanol in the reaction system, and add dichloromethane for extraction. The organic phase is washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated to obtain a white solid substance 1-8, which can be directly used in the next step.

Synthesis of compound 1-9:

Dissolve the intermediate 1-8 (129 mg, 0.29 mmol) in 20 ml of dichloromethane, add Dess-Martin oxidant (147 mg, 0.35 mmol) and solid sodium bicarbonate (29 mg, 0.35 mmol), and stir at room temperature. After the reaction is complete by TLC monitoring (ultraviolet), filter the reaction system, extract the filtrate with saturated sodium bicarbonate, and the organic layer is purified by saturated sodium salt.

The product was washed with water, dried over anhydrous sodium sulfate and concentrated. The product was separated and purified by flash column chromatography (CH2Cl2:MeOH=20:1) to obtain 77 mg of compound 1 as a white solid powder with a yield of 60%.

Synthesis of compound 1-10:

Compound 1-9 (129 mg, 0.29 mmol) was dissolved in dichloromethane solvent, acetic acid (19.2 mg, 0.32 mmol) and benzyl isocyanate (37.6 mg, 0.32 mmol) were added to react to obtain compound 1-10. Flash column chromatography (CH 2 Cl 2 :MeOH＝20:1) to separate and purify to obtain 126 mg of white solid powder compound 1-10 with a yield of 70%.

Synthesis of compound 1-11:

Compound 1-10 (187 mg, 0.3 mmol) was dissolved in methanol solvent, LiOH (0.6 mmol) was added and stirred to obtain compound 1-11. 2 Cl 2 :MeOH＝20:1) to separate and purify to obtain 148 mg of white solid powder compound 1-11 with a yield of 85%.

Synthesis of compound 1-12:

Compound 1-11 (174 mg, 0.3 mmol) was dissolved in dichloromethane solvent, Dess-Martin oxidant (152 mg, 0.36 mmol) was added, sodium bicarbonate (30 mg, 0.36 mmol) was added, and stirred to obtain a white solid powder compound 1-12 of 140 mg in total, with a yield of 80%.

1 H NMR(500MHz,Chloroform)δ9.76(s,1H),7.73(s,1H),7.39(s,1H),7.32–7.26(m,2H),7.22(s,1H),7 .20–7.10(m,3H),7.01(s,1H),6.82(s,1H),6.68(s,1H),6.14(s,1H),5.57(s,1H),5.43(s,1H),4.3 8(s,1H),4.32(d,J＝19.2Hz,2H),3.45(s,1H),3.35(s,1H),3.06(s,1H),2.20(dd,J＝15.4,2.3Hz,4H ),2.12–2.03(m,2H),1.92(s,1H),1.77(s,1H),1.73–1.67(m,3H),1.66–1.53(m,6H),1.37(s,1H).;

PATENT

WO2020030143

bioRxiv (2020), 1-17

• [1]. Ullrich S, Nitsche C. The SARS-CoV-2 main protease as drug target. Bioorg Med Chem Lett. 2020 Sep 1;30(17):127377.  [Content Brief]
• [2]. Shang W, et al. In vitro and in vivo evaluation of the main protease inhibitor FB2001 against SARS-CoV-2. Antiviral Res. 2022 Dec;208:105450.  [Content Brief]

///BOFUTRELVIR, FB2001, FB 2001, Phase 3, COVID 2019, T5UX5SKK2S, Mpro inhibitor, DC-402234, DC402234, MPI-10