Thirty-three patient fungal isolates were studied by broth macrodilution methods for susceptibility to novel azole derivatives with a morpholine ring, UR-9746 and UR-9751, and fluconazole. MICs (micrograms/ml) ranged widely, but none had lower MICs for Candida albicans or Cryptococcus neoformans than UR-9751. Fluconazole and UR-9751 had the most activity versus other Candida species. Activity was demonstrated versus endemic fungal pathogens. Aspergillus species were generally resistant, although modest activity was seen. UR-9746 and UR-9751 are active in vitro, with a potency comparable to that of fluconazole.