Improved process for the preparation of Crystalline Form of (4-[7-(6-Cyano-5-trifluoromethylpyridin-3-yl)-8-oxo-6-thioxo-5,7-diazaspiro[3.4]oct-5-yl]-2-fluoro-N-methylbenzamide)

摘要

Present disclosure is focused on the preparation of crystalline form (Form A) of (4-[7-(6-Cyano-5- trifluoromethylpyridin-3-yi)-8-oxo-6-thioxo-5,7--diazaspiro[3.4]oct-5-yl]-2-fluoro-N-methylbenzamide)(herein below referred as a compound 1) WO2007126765 discloses preparation of compound 1 by reacting 5-isolhiocyanalo-3-(trifluoromethyl) pyridine-2-carbonitrile and 4-(l-cyanocyclobutylamino)-2-fluoro-N-methyl benzamide using microwave. Further WO2013184681 discloses different polymorphic forms of compound I and their preparation using different solvent system. The present disclosure for preparation of crystalline form (Form A) of compound I is illustrated with following example.