Synthesis of Spiromamakone A Benzo Analogues via Double Oxa-Michael Addition of 1,8-Dihydroxynaphthalene
作者:Hirokazu Tsukamoto、Shogo Hanada、Koichi Kumasaka、Noritaka Kagaya、Miho Izumikawa、Kazuo Shin-ya、Takayuki Doi
DOI:10.1021/acs.orglett.6b02328
日期:2016.10.7
Two benzo analogues of cytotoxic spiromamakone A, comprising carbon atoms with the same oxidation state and unsaturation degree as those of the natural products, are synthesized and biologically evaluated. Substitution of alpha,alpha'-dioxoketene dithioacetals, derived from 1,3-cyclopentanediones with protected (2-formylphenyl)magnesium' bromide and 1,8-ffihydroxynaphthalene, followed by deprotection, generated these analogues via an intramolecular aldol reaction. The cytotoxicity of benzo analogues and synthetic intermediates against cervical carcinoma HeLa cells shows the necessity of the 4-cydopentene-1,3-dione moiety for biological activity.