Author/Authors :
Zhen Zhang، نويسنده , , Ying-Tong Di، نويسنده , , Yue-Hu Wang، نويسنده , , Zhen Zhang، نويسنده , , Shu-Zhen Mu، نويسنده , , Xin-Fang Wang، نويسنده , , Yu Zhang، نويسنده , , Cheng-jian Tan، نويسنده , , Qiang Zhang، نويسنده , , Xiao-Hui Yan، نويسنده , , Jie Guo، نويسنده , , Chun-Shun Li، نويسنده , , Xiao-Jiang Hao، نويسنده ,
Abstract :
Five new oxindole alkaloids, gelegamines A–E (1–5), were isolated from the roots of Gelsemium elegans. Their structures were extensively elucidated on the basis of spectroscopic analysis. Among them, the epoxy ring (C-19/C-20) of gelegamine A (1) was assigned as α-orientation by ROESY experiment and DFT method at B3LYP/6-31g(d) level, and gelegamine B (2) is the first humantenine-type alkaloid with 19-(E) ethylidene configuration. The absolute configurations of gelegamines A–E (1–5) were established on biosynthetic consideration coupled with CD experiments.
Keywords :
Loganiaceae , Gelsemium elegans , oxindole alkaloid , Gelegamines A–E
