Known and novel terpenes from Buddleja globosa displaying selective antifungal activity against dermatophytes

Lipophilic extracts of the stembark of Buddleja globosa were found to have antifungal activity at 125 mu g/mL against three dermatophytic fungal speci es but had no activity at 1000 mu g/mL against four other fungal species or two yeast species. Bioassay-guided fractionation of Si gel column eluates using the sensitive fungal species resulted in active fractions from which were isolated five compounds that were characterized by spectroscopic metho ds as one novel and four known compounds. The known compounds were the dite rpene buddlejone (1), the bisditerpene maytenone, and the two sesquiterpene s buddledin A and buddledin B, while the novel compound was characterized a s the diterpene deoxybuddlejone (2). The minimum inhibitory concentration o f all the compounds was determined against all the microorganisms under tes t, and buddledins A and B were shown to exhibit the greatest antifungal act ivity, with values of 43 mu M and 51 mu M, respectively, against the sensit ive fungi Trichophyton rubrum, Tricophyton interdigitale, and Epidermophyto n floccosum.