Evaluation on antimicrobial potential of dipterocarpol and dammarenolic acid derivatives from Dipterocarpus alatus

Abstract

Derivatives of natural dipterocarpol, dammarenolic acid and semisynthetic hollongdione were modified by the Beckman rearrangement 2 type, amination and Willgerodt - Kindler reactions. The structures of new compounds were confirmed by MS, 1H-NMR and 13C-NMR spectroscopic analysis. Antibacterial and antifungal activities of the compounds were estimated at the University of Queensland (Australia). The result of the in vitro antimicrobial inhibitory activity revealed N-methylpiperazinyl amide of dammarenolic acid a new lead compound with significant antifungal activity against Cryptococcus neoformans var. Grubii (MICs ≤ 0.25 μg/ml) being about ≈ 30 fold more active than the reference compound of fluconazole.