AN IMPROVED PROCESS FOR THE MANUFACTURE OF TOPIRAMATE

摘要

An improved process for the manufacture of 2,3:4,5-bis-O-(1-methylethylidene)-β-D-fructopyranose sulfamate, viz. Topiramate is reported. It consists of subjecting an intermediate of the formula 2,3:4,5-bis-O-(1-methylethylidene)-β-D-fructopyranose to a sulfamoylation reaction with sulfamoyl halide in a suitable solvent of high dielectric constant and in presence of a suitable organic base at a temperature from -50 to 100 C followed by extraction and crystallization to afford a crude product which is finally crystallized from a solvent to afford the title derivative in vastly improved yields and quality. Further the process affords the title compound possessing a good stability.