Reaction #82370

Reaction equation

N2 [3(S)-[[N-(benzyloxycarbonyl)-3-(methylsulphinyl)-L-alanyl]amino]-2(R)-hydroxy-4-phenylbutyl]-N1 -tert.butyl-L-prolinamide N2 -oxide

3-chloroperbenzoic acid

→

N2 [3(S)-[[N-(benzyloxycarbonyl)-3-(methylsulphonyl)-L-alanyl]amino]-2(R)-hydroxy-4-phenylbutyl]-N1 -tert.butyl-L-prolinamide N2 -oxide monohydrate

Yield 34.5%

Solvents

methanol

Conditions

Workup

1. 1
   OtherThe solvent was removed by evaporation
2. 2
   Otherthe residue was partitioned between dichloromethane and 2M sodium hydroxide solution
3. 3
   OtherThe organic phase was evaporated
4. 4
   Otherthe residue was crystallized from ethyl acetate/n-hexane

Procedure

A solution of 154 mg of N2 -[3(S)-[[N-(benzyloxycarbonyl)-3-(methylsulphinyl)-L-alanyl]amino]-2(R)-hydroxy-4-phenylbutyl]-N1 -tert.butyl-L-prolinamide N2 -oxide (two diastereomers) in 5 ml of methanol was treated with 84 mg of 3-chloroperbenzoic acid and the solution was stirred at 20° C. for 16 hours. The solvent was removed by evaporation and the residue was partitioned between dichloromethane and 2M sodium hydroxide solution. The organic phase was evaporated and the residue was crystallized from ethyl acetate/n-hexane to give 28 mg of N2 -[3(S)-[[N-(benzyloxycarbonyl)-3-(methylsulphonyl)-L-alanyl]amino]-2(R)-hydroxy-4-phenylbutyl]-N1 -tert.butyl-L-prolinamide N2 -oxide monohydrate; MS: m/e 633 [M+H]+.

Source