RESUMO
Objective: To study the chemical constituents in the ethanol extract from Paliurus ramosissimus. Methods: The compounds were isolated and purified by repeated silica gel column chromatographies and HPLC. The structures of the compounds were identified on the basis of chemical and spectral methods of NMR, MS, etc. Combined with the MTT method, the inhibitory effect of compound 2 in vitro against the HepG-2 and HeLa cells was assayed. Results: Two new compounds were isolated from P. ramosissimus and identified as betulinic acid (1) and 2α,27-di (E-p-hydroxy cinnamoyloxy)-betulinic acid (2) for the first time. The IC50 values of compound 2 are 20.34 and 14.83 μmol/L against the HepG-2 and HeLa cells. Conclusion: Compound 2 is a new compound named as paliurusene, which belongs to triterpenoids and shows the obvious cytotoxicity in vitro against the cancer cell lines.