Substituted 5,6-dihydrofuro[3,2-f]-1,2-benzisoxazole-6-carboxylic acids: high-ceiling diuretics with uricosuric activity

Abstract
A series of substituted 5,6-dihydrofuro[3,2-f]-1,2-benzisoxazoles was prepared and evaluated for their saluretic and uricosuric properties. Pharmacological evaluation of the title compounds was carried out in mice, rats, dogs and monkeys. The diuretic/saluretic nature of these compounds was observed in all spp.; the uricosuric activity was best seen in the Cebus monkey. Evaluation of the enantiomers of 8-chloro-3-(o-fluorphenyl)-5,6-dihydrofuro[3,2-f]-1,2-benzisoxazole-6-carboxylic acid revealed that only the (+) enantiomer displayed diuretic and saluretic activity; both enantiomers possessed uricosuric activity. X-ray analysis showed that the (.sbd.)enantiomer possesses the 2R configuration.