Diisopropylethylamine → HCID 56982734, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of (2S,4S)-4-(4-methoxybenzyl)thio-1-(4-nitrobenzyloxycarbonyl)-L-proline (2.87 g) in anhydrous tetrahydrofuran (30 ml), N,N'-carbonyldiimidazole (1.25 g) was added, followed by stirring at 30° C. for one hour. To the reaction mixture, N,N-diisopropylethylamine (1.68 ml) and a solution of (3S)-3-[3-hydroxy-4-(4-nitrobenzyloxycarbonyl)aminobutanoylamino]pyrrolidine trifluoroacetate (3.19 g) in anhydrous tetrahydrofuran (30 ml) was added. The resulting mixture was allowed to stand overnight at room temperature. The reaction mixture was concentrated by evaporation under reduced pressure and ethyl acetate was added to the residue. The resulting mixture was washed successively with water and saturated saline, dried over anhydrous magnesium sulfate and concentrated by evaporation under reduced pressure. The residue was purified by chromatography (dichloromethane-ethyl acetate-methanol) through a silica gel column, whereby 3.81 g of the title compound were obtained as an amorphous substance.

Provenance & Evidence