Thiobenzoic Acid → (2S,4S)-4-benzoylthio-2-(carbamoylmethyl)thiomethyl-1-(4-nitrobenzyloxycarbonyl)pyrrolidine

To a suspension of sodium hydride (62.8% in oil) (0.22 g) in N,N-dimethylformamide (5 ml) was added dropwise thiobenzoic S-acid (0.66 ml) under ice-cooling. After stirring under the same condition for 30 minutes, this solution was added to a solution of (2S,4R)-2-(carbamoylmethyl)thiomethyl-4-methanesulfonyloxy-1-(4-nitrobenzyloxycarbonyl)pyrrolidine (1.68 g) in N,N-dimethylformamide (20 ml) at ambient temperature. The mixture was stirred at 70°-80° C. for 1 hour. The reaction mixture was poured into ice-water (50 ml) and extracted twice with ethyl acetate (50 ml). The organic layer was washed with saturated aqueous sodium chloride, dried over anhydrous magnesium sulfate and evaporated in vacuo t.o give a residue. The residue was chromatographed on silica gel (100 g) eluting with a mixture of dichloromethane and acetone (5:1, V/V). The fractions containing the desired compound were collected and evaporated in vacuo to give (2S,4S)-4-benzoylthio-2-(carbamoylmethyl)thiomethyl-1-(4-nitrobenzyloxycarbonyl)pyrrolidine (0.87 g).

1. temperaturecooling
2. stirringThe mixture was stirred at 70°-80° C. for 1 hour
3. extractionextracted twice with ethyl acetate (50 ml)
4. washThe organic layer was washed with saturated aqueous sodium chloride
5. dry with materialdried over anhydrous magnesium sulfate
6. customevaporated in vacuo
7. customt.o give a residue
8. customThe residue was chromatographed on silica gel (100 g)
9. washeluting with a mixture of dichloromethane and acetone (5:1, V/V)
10. additionThe fractions containing the desired compound
11. customwere collected
12. customevaporated in vacuo

ORD record

ord-6a0721e1af3e4bbb932af631deafac5a

Source dataset

uspto-grants-1991_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05061804