SOME TRITERPENOIDS AND STEROIDS FROM THE LICHEN LOBARIA ORIENTALIS, LOBARIACEAE

Chemical investigation of the ethyl acetate extract of the lichen Lobaria orientalis,Lobariaceae, collected in Vietnam, afforded six known compounds, including four triterpenoids,zeorin (1), 16β-acetoxyhopane-6α,22-diol (2), retigeric acid A (3), retigeric acid B (4), togetherwith two steroids, ergosterol-5α,8α-peroxide (5) and cerevisterol (6). Their chemical structureswere elucidated by spectroscopic data analysis and comparison with those reported in theliterature. The cytotoxic activities of some compounds against liver hepatocellular carcinoma(HepG2), human lung cancer (NCI-H460), human epithelial carcinoma (HeLa) and humanbreast cancer (MCF-7) cell lines were evaluated. Compound 2 exhibited good cytotoxicityagainst MCF-7 cancer cell line with IC50 value of 21.10 μg/mL. This is the first time compounds(1), (2), (6) are reported in the Lobaria genus.