Alkaloids from leaves and stem bark of Ervatamia peduncularis
作者:Monique Zèches-Hanrot、Jean-Marc Nuzillard、Bernard Richard、Hubert Schaller、Hamid A. Hadi、Thierry Sévenet、Louisette Le Men-Olivier
DOI:10.1016/0031-9422(95)00152-w
日期:1995.9
Chemical study of the leaves and stem bark of Ervatamia peduncularis afforded two novel bisindole alkaloids, pedunculine and peduncularidine, together with seven known alkaloids, coronaridine, coronaridine hydroxyindolenine, eglandine, heyneanine, eglandulosine, heyneanine hydroxyindolenine and N(1)-methyl-aspidos-permidine. Structural elucidation of the new alkaloids was based on their spectral data
Regiodivergent Asymmetric Pyridinium Additions: Mechanistic Insight and Synthetic Applications
作者:Thiago A. Grigolo、Joel M. Smith
DOI:10.1002/chem.202202813
日期:2022.12.9
A regiodivergentasymmetric dearomatization of readily accessible pyridines has enabled the redox-economic synthesis of both (+)-N-Methylaspidospermidine and (−)-Paroxetine. A mechanistic rationale for the regiodivergentpyridiniumadditions and evaluation of their scope was also explored.
A homo-Mannich reaction of cyclopropanol with an iminium ion, generated by an asymmetric allylic dearomatization of indole, has been developed to construct a tricyclic hydrocarbazole core. This approach enables a collective asymmetric synthesis of ibophyllidine, Aspidosperma, Kopsia, and Melodinus alkaloids having either a five-, six-, or seven-membered E ring.
环丙醇与吲哚不对称烯丙基脱芳构化产生的亚胺离子的均曼尼希反应已被开发用于构建三环氢咔唑核。这种方法能够集体不对称合成具有五元、六元或七元 E 环的 ibophyllidine、Aspidosperma、Kopsia和Melodinus生物碱。