Intramolecular Radical CyclizationRing-Closing Metathesis Approach to Fused Polycyclic Ethers. Convergent Synthesis and Conformational Analysis of the (E)FGH Ring System of Ciguatoxin
作者:Makoto Sasaki、Tetsuji Noguchi、Kazuo Tachibana
DOI:10.1021/jo010974p
日期:2002.5.1
A convergent synthetic route to the (E)FGH ring system 4 of ciguatoxins, the causative toxins for ciguatera fish poisoning, has been developed. The synthesis features convergent coupling to form dioxane acetal, regioselective acetal cleavage by diethylaluminum phenylthiolate or diisobutylaluminum phenylselenolate followed by intramolecular radical cyclization to construct the oxepane ring G, and a
已经开发出一种合成的合成路线,可通往雪茄鱼中毒的致病毒素-雪茄毒素的(E)FGH环系统4。该合成具有会聚偶联形成二恶烷缩醛,苯硫醇二乙基铝或苯硒酸二异丁酯铝的区域选择性缩醛裂解,随后分子内自由基环化以构建氧杂环丁烷环G和闭环易位反应以形成六氢氧肟酮环F的特征。四环模型系统4以两种构象(UP和DOWN构象)的5:1平衡混合物形式存在,其中UP占主导地位。这是第一个说明了对UP构象子比对DOWN构象子的偏好的例证,对天然雪茄毒素的偏好被发现。