PROCESS FOR PRODUCING CRYSTALS OF POLYMORPHIC 2-(3- CYANO-4- ISOBUTYLOXYPHENY L)-4-METHYL-5- THIAZOLECARBOXYL IC ACID BY POOR- SOLVENT ADDITION METHOD

摘要

pDisclosed is a process for producing A-form crystals of 2-(3-cyamo-4-isobutytoxyphenyl)-4-methyl-5-thiazotecarboxylic acid, comprising: a step of dissolving by heating 2-(3-cyano-4-isobutyloxyphenyl)-4-methyl-5-thiazolecarboxylic acid in one or a plurality of solvents as a good solvent, selected from the group consisting of 1-propmol, 2-propanol, ethanol, and acetone, a step of cooling the solution; and a step of adding to the solution a hydrocarbon solvent as a poor solvent./p [EP2455372A1]