| 摘要 |
The present invention relates to an improved process for the preparation Of (2S,3aS,7aS)-1-[(2S)-2-[[(1S)-1-(ethoxycarbonyl)butyl]amino]3-S-oxopropyl]octahydro-1H-indole-2-carboxylic acid benzyl ester (the compound of formula II) comprising reacting (2S,3aS,7aS)-octahydro-1H-indole-2-carboxylic acid phenylmethyl ester 4-methylbenzenesulfonate (the compound of formula III) with N-[(S)-ethoxycarbonyl-1-butyl]-(S)-alanine (the compound of formula IV), using 1-hydroxybenzotriazole (HOBT), dicyclohexylcarbodimide (DCC) and triethylamine in the presence of toluene as a solvent at a temperature of 5-40° C. |
