Enantioselective total synthesis of (+)-rubrobramide, (+)-talaramide A, and (−)-berkeleyamide D by a skeletal diversification strategy
作者:Kosaku Tanaka、Kenichi Kobayashi、Hiroshi Kogen
DOI:10.1039/d1cc04290d
日期:——
A unified synthesis of (+)-rubrobramide, (+)-talaramide A, and (−)-berkeleyamide D was achieved from the vinylogous esters by a skeletal diversification strategy based on regioselective 5-exo or 6-endo cyclization. This report describes the first enantioselective total synthesis of (+)-rubrobramide and (+)-talaramide A. Additionally, synthetic spirocyclic lactam compounds, including (−)-berkeleyamide
(+)-rubrobramide、(+)-talaramide A 和 (-)-berkeleyamide D 的统一合成是通过基于区域选择性 5- exo或 6- end环化的骨架多样化策略从乙烯基酯中实现的。本报告描述了 (+)-rubrobramide 和 (+)-talaramide A 的首次对映选择性全合成。 此外,合成的螺环内酰胺化合物,包括 (-)-berkeleyamide D,对潜在治疗的淀粉样蛋白-β 聚集显示出中等抑制活性阿尔茨海默病。
Short Synthesis of Berkeleyamide D and Determination of the Absolute Configuration by the Vibrational Circular Dichroism Exciton Chirality Method
reaction followed by an intramolecular spirocyclization via an epoxide-opening reaction. Following optical resolution by chiral HPLC, the absoluteconfigurations of both enantiomers of berkeleyamide D were determined by the vibrational circulardichroism exciton chiralitymethod.
antibacterial and cytotoxic activity of seven racemic lactams and both enantiomers of flavipucine were evaluated. Of the compounds tested in this study, flavipucine and phenylflavipucine displayed bactericidal activity against Bacillus subtilis. These results indicate that the pyridione epoxide moiety is a pharmacophore for antibacterial activity against B. subtilis. Flavipucine showed cytotoxic activity against