One novel（named palcernuine, 1） and five known cernuane-type（2–6） alkaloids were isolated from the whole plant of Palhinhaea cernua f. sikkimensis. The structure of 1, possessing an unprecedented [5/6/6/6]-tetrac...One novel（named palcernuine, 1） and five known cernuane-type（2–6） alkaloids were isolated from the whole plant of Palhinhaea cernua f. sikkimensis. The structure of 1, possessing an unprecedented [5/6/6/6]-tetracyclic ring system containing two nitrogen atoms, was established on the basis of spectroscopic methods, and its absolute configuration was determined by comparison of the experimental and calculated electronic circular dichroism（ECD） spectra. A plausible biosynthetic pathway to 1 is proposed.展开更多
To investigate saponins from the roots of Pulsatilla cernua （Thunb.） Bercht. et Opiz., two new compounds together with five known trlterpenold saponins were isolated. The structures of the two new trlterpenoid sapon...To investigate saponins from the roots of Pulsatilla cernua （Thunb.） Bercht. et Opiz., two new compounds together with five known trlterpenold saponins were isolated. The structures of the two new trlterpenoid saponins, named cernuasides A and B, were elucidated as 3-O-[β-D-xylopyranosyl（1-）2）]-[α-L-rhamnopyranosyl（1-）4）]-α-L- arablnopyranosyl hederagenin 28-O-β-D-glucopyranosyl ester （compound 1） and 3-O-[α-L-arabinopyranosyl（1→）3）]- [α-L-rhamnopyranosyl （1→）2）]-α-L-arabinopyranosyl hederagenin 28-O-β-D-glucopyranosyl ester （compound 2） by 1D, 2D-NMR techniques, ESIMS analysis, as well as chemical methods.展开更多
基金supported by NSFC grants (Nos. 21472021, 81273401, 81202420)grants from the Ph.D. Programs Foundation of Ministry of Education (MOE) of China (Nos. 20120071110049, 20120071120049)the National Basic Research Program of China (973 Program, No. 2013CB530700)
文摘One novel（named palcernuine, 1） and five known cernuane-type（2–6） alkaloids were isolated from the whole plant of Palhinhaea cernua f. sikkimensis. The structure of 1, possessing an unprecedented [5/6/6/6]-tetracyclic ring system containing two nitrogen atoms, was established on the basis of spectroscopic methods, and its absolute configuration was determined by comparison of the experimental and calculated electronic circular dichroism（ECD） spectra. A plausible biosynthetic pathway to 1 is proposed.
文摘To investigate saponins from the roots of Pulsatilla cernua （Thunb.） Bercht. et Opiz., two new compounds together with five known trlterpenold saponins were isolated. The structures of the two new trlterpenoid saponins, named cernuasides A and B, were elucidated as 3-O-[β-D-xylopyranosyl（1-）2）]-[α-L-rhamnopyranosyl（1-）4）]-α-L- arablnopyranosyl hederagenin 28-O-β-D-glucopyranosyl ester （compound 1） and 3-O-[α-L-arabinopyranosyl（1→）3）]- [α-L-rhamnopyranosyl （1→）2）]-α-L-arabinopyranosyl hederagenin 28-O-β-D-glucopyranosyl ester （compound 2） by 1D, 2D-NMR techniques, ESIMS analysis, as well as chemical methods.
