RESUMO
Objective: To investigate the chemical consituents from the active fraction in the roots and rhizomes of Cynanchum paniculatum with reversal activity of multidrug resistance. Methods: The active fraction was evaluated for reversing activities toward three human drug-resistance cell lines to clininally common used anticancer chemotherapeutic drugs. The compounds were isolated and purified by chromatography on ODS and preparative HPLC. Their structures were elucidated on the basis of chemical and spectroscopic methods, including MS, 1D, and 2D NMR spectral techniques. Results: The active fraction exhibited the significant effects in sensitization of human drug-resistance on gastric carcinoma cell line SGC-7901/VCR and human drug-resistance on colonic carcinoma cell line HCT-8/VCR to fluorouracil (5-FU). Nine compounds were isolated and identified as hancogenin B 3-O-β-D- oleandropyranoside (1), 3β,14-dihydroxy-14β-pregn-5-en-20-one (2), neocynapanogenin F (3), glaucogenin A (4), glaucogenin C (5), neocynapanogenin F 3-O-β-D-oleandropyranoside (6), glaucogenin C 3-O-β-D-thevetoside (7), glaucogenin A 3-O-β-D- oleandropyranoside (8), and 20-hydroxypregna-4,6-dien-3-one (9). Conclusion: Compound 1 is a new steroidal saponin named paniculatumoside D. C21 Steroids isolated from the active fraction in the roots and rhizomes of C. paniculatum have the potential value as multidrug resistance reversing agents.