Design and synthesis of novel triazole antifungal derivatives by structure-based bioisosterism.

The incidence of life-threatening fungal infections is increasing dramatically. In an attempt to develop novel antifungal agents, our previously synthesized phenoxyalkylpiperazine triazole derivatives were used as lead structures for further optimization. By means of structure-based bioisosterism, triazolone was used as a new bioisostere of oxygen atom. This type of bioisosteric replacement can improve the water solubility without loss of hydrogen-bonding interaction with the target enzyme. A series of triazolone-containing triazoles were rationally designed and synthesized. As compared with fluconazole, several compounds showed higher antifungal activity with broader spectrum, suggesting their potential for further evaluations.