反应详情

Aqueous N-sodium hydroxide solution (2.5 ml.) was added to a solution of N-[1-ethoxycarbonyl-5,5-ethylenedioxy-5-(2-thienyl)pentyl]-L-alanyl-L-proline t-butyl ester (Example 17; 1.2 g.) in ethanol (7.5 ml.) and the mixture was stirred at laboratory temperature for 24 hours and the ethanol was then removed by evaporation under reduced pressure. Water (10 ml.) was added, the solution was washed with dichloromethane and then acidified to pH 5 with aqueous 2N hydrochloric acid, and the mixture was filtered. There was thus obtained as solid residue Isomer A of N-[1-carboxy-5,5-ethylenedioxy-5-(2-thienyl)pentyl]-L-alanyl-L-proline t-butyl ester.

1. customthe ethanol was then removed by evaporation under reduced pressure
2. additionWater (10 ml.) was added
3. washthe solution was washed with dichloromethane
4. filtrationthe mixture was filtered