反应详情

A solution of 300 mg of N-[(S)-α-[[[1-methyl-1-[methyl-[2-(2-pyridyl)ethyl]carbamoyl]ethyl]sulfonyl]methyl]hydrocinnamoyl]-3-(thiazol-4-yl)-D,L-alanine methyl ester in 2.5 ml of dioxan was treated with a solution of 24.3 mg of lithium hydroxide hydrate in 1 ml of water and stirred at 50 for 3 hours. Subsequently, the solution was partitioned between ethyl acetate and water and the organic phase was extracted three times with water. The aqueous extracts were adjusted to pH 2 with ethyl acetate and with 2N hydrochloric acid and evaporated under reduced pressure. There were obtained 365 mg of N-[(S)-α-[[[1 -methyl-1-[methyl-[2-(2-pyridyl)ethyl]carbamoyl]ethyl]sulfonyl]methyl]hydrocinnamoyl]-3-(thiazol-4-yl)-D ,L-alanine as a colourless foam which was used directly in the next step.

1. customSubsequently, the solution was partitioned between ethyl acetate and water
2. extractionthe organic phase was extracted three times with water
3. customevaporated under reduced pressure