Hepatoprotective hemiterpene glycosides from the rhizome of Cibotium barometz (L.) J. Sm.

Five previously undescribed hemiterpene glycosides, cibotiumbarosides E-I, and two known hemiterpene glucosides, were isolated from the rhizome of Cibotium barometz (L.) J. Sm. The structures of cibotiumbarosides E-I were established by 1D and 2D NMR spectroscopic analyses and HRMS. The absolute configuration of the aglycone of cibotiumbaroside E was assigned by calculated ECD with the TDDFT method. Cibotiumbarosides F and I both exhibited remarkable hepatoprotective activity against APAP-induced acute liver damage in vitro, which were more effective than the positive control, bicyclol. On the other hand, seven hemiterpene glycosides were all inactive in assays of cytotoxicity, neuroprotection, antidiabetes and anti-inflammation.