To a stirred mixture of 2-amino-4-[4-(diphenylmethoxy)piperidinomethyl]thiazole (0.78 g), N-methylmorpholine (1.15 ml) in N,N-dimethylformamide (8 ml) was added dropwise a solution of methanesulfonyl chloride (0.5 g) in dichloromethane (0.5 ml) under ice-bath cooling. After 1 hour, the reaction mixture was filtered. The filtrate was made basic with 1N sodium hydroxide solution (12 ml). After being stirred for 30 minutes, the mixture was neutralized with 1N hydrochloric acid and extracted with dichloromethane (40 ml×2). The extract was washed with a saturated aqueous solution of sodium chloride and dried over magnesium sulfate. The solvent was distilled off and the residue was subjected to column chromatography on silica gel, and eluted with a mixture of chloroform and methanol (10:1 V/V). The fractions containing the object compound were combined and concentrated under reduced pressure to give white crystals. The crystals were recrystallized from ethanol to give 2-mesylamino-4-[4-(diphenylmethoxy)piperidinomethyl]thiazole (0.32 g).
