| 摘要 |
FIELD: organic chemistry, chemical technology. ^ SUBSTANCE: invention relates to methods for preparing N-(trans-4-isopropylcyclohexylcarbonyl)-D-phenylalanine (nateglinide). Method for preparing nateglinide crystals of H-type is carried out by addition of inorganic acid to reaction mixture containing nateglinide to provide its acidification. The reaction mixture is prepared by interaction of trans-4-isopropylcyclohexylcarbonyl chloride with D-phenylalanine in a mixed solvent consisting of a ketone solvent and water in the presence of alkali. The ratio of water to ketone solvent is from 10:1 to 0.5:1. Temperature of the mixture is brought about to 58-72°C and concentration of ketone solvent - up to value above 8 wt.-% and less 22 wt.-% for carrying out precipitation of nateglinide crystals. Invention proposes variant for preparing nateglinide crystals of H-type. Also, invention proposes crystals of nateglinide of H-type showing average value of longitudinal axis from 1 to 5 mm and that for transverse axis from 0.1 to 0.5 mm. Invention provides enhancing effectiveness in isolation of nateglinide crystals. ^ EFFECT: improved preparing methods. ^ 10 cl, 1 tbl, 13 ex |
