Hydrochloric Acid → Thiophene-3-sulfonamide

Participants

Reaction Steps

NaOH (1.5 N, 250 ml) was added to N-(4-chloro-3-methyl-5-isoxazolyl)-2-[(4,5-dimethoxy-2-methoxycarbonylphenyl)aminocarbonyl]thiophene-3-sulfonamide (EXAMPLE 149); 410 mg). The resulting suspension was stirred at room temperature overnight to give a clear solution. The mixture was acidified using concentrated HCl with cooling. The resulting precipitate was filtered, washed with water (3×50 ml) and dried on a lyophilyzer to give N-(4-chloro-3-methyl-5-isoxazolyl)2-{[2-carboxyl-4,5-(methylenedioxy)phenyl]aminocarbonyl})thiophene-3-sulfonamide as a yellow powder (87% yield, m.p. 192-195° C.).

Provenance & Evidence