[Chemical constituents from Pteris dispar and their anti-tumor activity in vitro]

The dried whole plant of Pteris dispar were milled and extracted with 95% EtOH. The resulting dried extract was isolated by kinds of chromatographic column, including polyamide, Sephadex LH-20, preparative HPLC. As a result, ten diterpenes were isolated from the plant. By analyzing of ESI-MS and NMR spectroscopic data, the structures were established as geopyxin B(1), geopyxin E(2), ent-11α-hydroxy-18-acetoxykaur-16-ene(3), ent-14β-hydroxy-18-acetoxykaur-16-ene(4), neolaxiflorin L(5), ent-3β,19-dihydroxy-kaur-16-ene(6), ent-3β-hydroxy-kaur-16-ene(7), 7β,17-dihydroxy-16α-ent-kauran-19-oic acid 19-O-β-D-glucopyranoside ester(8), crotonkinin C(9)and crotonkinin C(10). Compounds 1-10 were obtained from P. dispar for the first time. Compounds 1 and 2 showed moderate activities against Bel-7402 with IC₅₀ values of 7.50 and 10.60 μmol•L⁻¹, and against HepG2 with IC₅₀ values of 6.68,11.80 μmol•L⁻¹, respectively.