Studies on Uricosuric Diuretics: I: Syntheses and Activities of Xanthonyloxyacetic Acids and Dihy-drofuroxanthone-2-carboxylic Acids

A series of substituted xanthonyloxyacetic acids (5 and 6), l,2-dihydrofuro[2,3-c]xanthone-2-carboxylic acids (7) and 2,3-dihydrofuro[3,2-A]xanthone-2-carboxylic acids (8) were synthesized and tested for diuretic and uricosuric activities in rats. Most of the xanthon-3-yloxyacetic acids (5) and 7 showed potent diuretic activities, while 8 had lower activities. Uricosuric activities were found in 5c, 5f, 5k, 5m, 5o, 5p, 5r, 7m, 7p and 8q.