Chemical constituents and biological activity from the stem barks of Croton oblongifolius Roxb. from Amphoe Dan Sai, Loei province

In the investigation of chemical constituents of the stem barks of Croton oblongifolius Roxb., a new diterpenoids compound, cleistantha-4(18), 13(17), 15-trien-3-oic acid (1) was isolated from crude hexane and crude ethyl acetate. Three derivatives of compound 1 was synthesized, such as: methyl cleistantha-4(18), 13(17), 15-trien-3-oate (2), cleistantha-4(18), 13(17), 15-trien-3-ol (3) and cleistanatha-4(18), 12, 15-trien-3-oic acid (4). The structure of the new compounds were established by spectroscopic data (IR, MS spectra, 1D and 2D NMR techniques including DEPT, COSY, NOESY, HMBC and HMQC). All of compounds were tested for cytoxicity against various human tumor cell lines (BT474 (breast), HEP-G2 (hepatoma), SW620 (colon), CHAGO (lung), and KATO-3 (gastric)). Compound 2 was active against Hep-G2 cell line, SW620 cell line, CHAGO cell line and KATO-3 cell line, in vitro, with IC50 value of 10.0, 9.2, 9.7 and 8.4 mug/ml, respectively. Compound 3 wasactive against BT474 cell line, Hep-G2 cell line, SW620 cell line, CHAGO cell line and KATO-3 cell line, in vitro, with IC50 value of 8.3, 5.8, 4.3, 4.9 and 5.0 mug/ml, respectively.