Fluconazole-COX Inhibitor Hybrids: A Dual-Acting Class of Antifungal Azoles

When used in combination
with azole antifungal drugs, cyclooxygenase
(COX) inhibitors such as ibuprofen improve antifungal efficacy. We
report the conjugation of a chiral antifungal azole pharmacophore
to COX inhibitors and the evaluation of activity of 24 hybrids. Hybrids
derived from ibuprofen and flurbiprofen were considerably more potent
than fluconazole and comparable to voriconazole against a panel of Candida species. The potencies of hybrids composed
of an S-configured azole pharmacophore were higher
than those with an R-configured pharmacophore. Tolerance,
defined as the ability of a subpopulation of cells to grow in the
presence of the drug, to the hybrids was lower than to fluconazole
and voriconazole. The hybrids were active against a mutant lacking
CYP51, the target of azole drugs, indicating that these agents act
via a dual mode of action. This study established that azole-COX inhibitor
hybrids are a novel class of potent antifungals with clinical potential.