[Chemical constituents from Pteris multifida and cytotoxic activity]

The materials were extracted by 95% ethanol, and the extracting solution was isolated by kinds of chromatographic columns including polyamide, MCI, preparative MPLC, and preparative HPLC. Eight diterpenes and two sesquiterpenes were isolated from the plant. On analysis of ESI-MS and NMR spectroscopic data, the structures were established as ent-3β-hydroxy-kaur-16-en-19-al (1), 4-epi-kaurenic acid (2), mitrekaurenone (3), 7β,16α,17-trihydroxy-ent-kauran-19-oic acid (4), crotonkinin E (5), crotonkinin F (6), pterisolic acid A (7), pterisolic acid C (8), (2R)-pterosin P (9), and dehydropterosin B (10). Compounds 1-6 were obtained from Pteris for the first time, and compounds 7-10 were obtained from P. ensiformis for the first time. Compounds 5-8 showed moderate activity against HCT-116, HepG2 and BGC-823 cell lines, separately.