Indium-Mediated Atom-Transfer and Reductive Radical Cyclizations of Iodoalkynes: Synthesis and Biological Evaluation of HIV-Protease Inhibitors
作者:Reiko Yanada、Yasuhiro Koh、Nobuaki Nishimori、Akira Matsumura、Shingo Obika、Hiroaki Mitsuya、Nobutaka Fujii、Yoshiji Takemoto
DOI:10.1021/jo035482m
日期:2004.4.1
Novel indium-mediated radical cyclization reactions of aliphatic iodoalkynes have been studied. Treatment of iodoalkynes with a catalytic amount of In (0.1 equiv) and I2 (0.05 equiv) promotes atom-transfer 5-exo cyclization to give five-membered alkenyl iodides. In contrast, reaction with In (2 equiv) and I2 (1 equiv) yields reductive 5-exo cyclization products via the same 5-exo cyclization. Both
已经研究了脂族碘炔的新型铟介导的自由基环化反应。用催化量的In(0.1当量)和I 2(0.05当量)处理碘炔促进了原子转移5-外环化,得到了五元链烯基碘。相反,与In(2当量)和I 2(1当量)的反应通过相同的5-exo环化反应生成还原性5-exo环化产物。这两个过程很可能都是由低价铟物种引发的。为了证明这些反应的多功能性,通过这种还原环化方法合成了光学活性的HIV蛋白酶抑制剂。其中有几种产品含有羟乙基胺二肽等位基因作为模拟过渡态的亚结构,被证明具有有效的活性(IC 50 = 5-39 nM),可抵抗多种HIV毒株,包括具有多重耐药性的变体。