Synthesis and Antiulcer Activity of 2-Amino-8H-indeno [1, 2-d] thiazole Derivatives

Abstract

A series of 8H-indeno [1, 2-d] thiazoles containing various N-substituted amino groups at the 2 position were synthesized by the reaction of 2-bromoindanones and N-substituted thioureas. Their anti-ulcerous activity was evaluated. Alkylamino derivatives have a more potent inhibitory behavior on ethanolinduced gastric ulcers compared with arylamino derivatives. We also studied the effect of various substituents on the both benzene and pyridine ring of 2-pyridylamino derivatives on ethanol-induced gastric ulcers. However no clear effects were observed. Among 3-morpholinopropylamino derivatives, 5-isopropyl-(21) and 7-chloro-2-(3-morpholinopropyl) amino-8H-indeno [1, 2-d] thiazole (25) showed a considerably stronger inhibitory behavior on hydrochloric acid-induced gastric ulcers than cetraxate hydrochloride. Furthermore, 3-morpholinopropylamino derivatives have potent inhibitory effects on gastric acid secretion in pylorus ligated rats.