(2-Arylhydrazonomethyl)-substituted xanthones as antimycotics: synthesis and fungistatic activity against Candida species.

A series of arylhydrazones derived from various 6,8-diacetoxy- or 6,8-dihydroxy-9-oxo-9H-xanthene carboxaldehydes were synthesized and evaluated for their in vitro antifungal properties against two human pathogenic yeasts (Candida albicans and C. krusei) according to a diffusion method. The activity was strongly dependent from the position of the (1-arylhydrazinyl-2-ylidene)methyl chain in the xanthone molecular skeleton. Compounds having the nitrogen side chain in the 4-position, with a further halogen substitution on the terminal phenyl ring showed fungistatic effects. Within this series, the 4-fluorophenylhydrazinyl derivative 13g exhibited the highest activity, particularly against C. krusei, with a greater efficacy than that of econazole, used as reference.