Sesquiterpene derivatives from Ocotea minarum leaves

Abstract

(+)-β-Sesquiphellandrene-12-oic acid (1) and 4-oxo-lanceolic acid (3), two new bisabolane derivatives; (+)-2-methyl-6[4-oxo-2-cyclohexen-1-yl]-2-(E)-heptenoic acid (4), a new nor-bisabolane derivative; (+)-(E)-exo-α-bergamoten-12-oic acid (5), a new bergamotene-type sesquiterpene; (2E,6E)-2,6-dimethyl-10-methylene-dodecatrienoic acid (6), a farnesene-type sesquiterpene reported for the first time as a natural product; and (–)-curcumen-12-oic acid (7), an aromatic bisabolene derivative that is new in Lauraceae, were obtained, together with lanceolic acid (2) and the terpenic lactone loliolide (8), from the leaves of Ocotea minarum. The chemical structures of these compounds were determined by 1D- and 2D-NMR and HRESIMS. Evaluated in vitro against standard strains of Candida species and Cryptococcus neoformans, compounds 1, 2, and 4-8 exhibited MIC values in the 50–100 μg mL–1 range.