摘要
Two pairs of enantiomers,(−)and(+)-securidanes A(1 and 2)and B(3 and 4)featuring unprecedented triarylmethane(TAM)skeletons,were isolated from Securidaca inappendiculata.Teir structures were established by spectroscopic data,X-ray crystallography,and CD analysis.A plausible biosynthetic pathway for 1−4 based on the co-isolated precursors was proposed.Bioinspired total synthesis of 1−4was completed in high yield,which in turn corroborated the biosynthetic hypothesis.Compounds 1−4 showed good inhibition against protein tyrosine phosphatase 1B(PTP1B).Te molecular docking demonstrated that the strongest inhibitor 3(IC50=7.52�M)reaches deeper into the binding pocket and has an additional H-bond.
基金
Te authors thank Professor S.Q.Tang of Guangxi Normal University for the identifcation of the plant material.Te National Natural Science Foundation(nos.21532007,U1302222,81321092)
and the Foundation from the MOST(2012CB721105)of China are gratefully acknowledged.