Chemical Constituents and Biological Studies of Origanum vulgare Linn.

Bioassay-guided isolation of methanolic extract of the leaves of Origanum vulgare Linn., yielded two protocatechuic acid ester derivatives, origanol A (1) and origanol B (2) along with ursolic acid (3), oleanolic acid (4), β-sitosterol (5), and triacontanol (6). Structures of the compound were established based on physical and spectral data (UV, IR, 1H and 13C NMR and mass). Origanol A (1) showed significant mushroom tyrosinase inhibition activity.