Benzene → tert-butyl 2-[({(2R,3S)-2-hydroxy-3-[((2S)-3-methyl-2-{3-[(2-methyl-1,3-thiazol-4-yl)methyl]-2-oxoimidazolidin-1-yl}butanoyl)amino]-4-phenylbutyl}amino)methyl]pyrrolidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

A solution of the product of Example 274C (59 mg) in ethanol:benzene (1 mL, 1:1) was treated with N-t-butoxylcarbonyl-(L)-prolinal (26 mg, 1 equivalent), stirred at 70° C. for 1 hour, cooled at 25° C., treated with NaBH4 (14 mg, 3 equivalents) at 25° C. and stirred for 16 hours. The mixture was quenched with saturated NH4Cl and partitioned between water and ethyl acetate. The organic layer was separated, dried over MgSO4, filtered and concentrated to give 85 mg of the crude title compound.

Provenance & Evidence