反应详情

A suspension of 5.51 g of (2S,4S)-4-(4-methoxy-benzylthio)-2-(1-piperazinylcarbonyl)-1-(4-nitrobenzyl-oxycarbonyl)pyrrolidine hydrochloride [prepared as described in Preparation 1(ii)] and 2.45 g of N-(4-nitrobenzyloxycarbonyl)formamidine in 10 ml of dry acetonitrile was stirred for 2 hours on a water-bath kept at 50° C. At the end of this time, the reaction mixture was freed from impurities by filtration, and the filtrate was concentrated by evaporation under reduced pressure. The resulting residue was purified by column chromatography through silica gel, using a 6:4 by volume mixture of ethyl acetate and acetonitrile as the eluent, to give 5.48 g of the title compound, as a powder.

1. customkept at 50° C
2. filtrationAt the end of this time, the reaction mixture was freed from impurities by filtration
3. concentrationthe filtrate was concentrated by evaporation under reduced pressure
4. customThe resulting residue was purified by column chromatography through silica gel
5. additionby volume mixture of ethyl acetate and acetonitrile as the eluent