【Abstract】 N (Trans 4 isopropylcyclohexyl 1 carbonyl) D phenylalanine,nateglide,is an effective drug to decrease blood sugar,which is under clinical trials in China.This compound has been reported to have two crystal types,of which the one is more suitable to prebare the drug.We have studied the preparation of different crystal types and discovered a new one that has not been reported in the literature.Their melting points,TGA DTA and DSC spectral data,IR and X ray powder diffraction spectra of all samples have been investigated with different crystal types,some have been compared with the commercial drug from abroad.Suggestions have been made to control the crystal type.更多还原