4-Methylmorpholine → HCID 71245451, compound

Participants

Reaction Steps

(2S)-1-((2R)-3-acetoxy-2-(benzyloxycarbonylamino)-butanoyl)-pyrrolidine-2-carboxylic acid (5) (1.3 g, 2.62 mmol) was dissolved in CH2Cl2 (15 mL), NMM (0.43 mL) and IBCF (0.51 mL) was added at −10° C. and stirred for 30 minutes under inert atmosphere. A mixture of(S)-methyl-3-hydroxy-2-((S)-pyrrolidine-2-carboxamido)-propionate (4) (992 mg, 3.93 mmol) and NMM (0.43 mL) in DMF (5 mL) were added drop wise to the reaction mixture and stirring was continued for another 3 h at RT. The reaction mixture was diluted with DCM (200 mL), washed with water (20 mL), citric acid solution (2×20 mL) and brine (2×50 mL). The separated organic layer was dried over anhydrous Na2SO4 and concentrated under reduced pressure. The obtained crude material was purified by silica gel column chromatography eluting with 5% CH3OH/CH2Cl2 to afford compound 6 (270 mg, 17.5%).

Provenance & Evidence