Synthesis and Toxicity of New Ring-Fused Imidazo[5,4-f]benzimidazolequinones and Mechanism Using Amine N-Oxide Cyclizations
作者:Vincent Fagan、Sarah Bonham、Patrick McArdle、Michael P. Carty、Fawaz Aldabbagh
DOI:10.1002/ejoc.201101687
日期:2012.4
hydrogen-bonded amine N-oxide intermediate. The amine N-oxide is shown to act as an oxidant in the aromatisation to the imidazole ring. X-ray crystal structures of the dimorpholine N-oxide intermediate and bis[1,4]oxazinoimidazo[5,4-f]benzimidazolequinone bis(trifluoroacetate) adduct are included. Two unsymmetrical quinones are shown to have greater cytotoxicity than the previously reported imidazobenzimidazolequinones
据报道,一种合成环稠合咪唑并[5,4-f]苯并咪唑的新途径可用于获得对称和不对称的醌类抗癌剂。甲酸中的 Oxone 允许邻叔氨基乙酰苯胺环化,以优异的产率得到稠环苯并咪唑和咪唑苯并咪唑。提出了这些氧化环化的机制,该机制通过氢键合的胺 N-氧化物中间体进行。胺N-氧化物显示在咪唑环的芳构化中充当氧化剂。包括二吗啉 N-氧化物中间体和双 [1,4] 恶嗪基咪唑并 [5,4-f] 苯并咪唑醌双(三氟乙酸盐)加合物的 X 射线晶体结构。两种不对称的醌被证明比以前报道的咪唑苯并咪唑醌具有更大的细胞毒性。