Synthetic approach to the quassinoid klaineanone - The synthesis of a potential intermediate by intramolecular cycloaddition.
作者:TETSUJI KAMETANI、MASATOSHI CHIHIRO、TOSHIO HONDA、KEIICHIRO FUKUMOTO
DOI:10.1248/cpb.28.2468
日期:——
Thermolysis of 4-acetoxymethylene-2-[2-benzyloxy-2-(5-methoxy-3-methylbenzo-cyclobuten-1-yl] ethyl-2-methylcyclopentan-1, 3-dione 1-ethylene ketal (21) gave the stachane-type tetracyclic compound (24), whose deketalization afforded 26, a potential synthetic intermediate to the quassinoid klaineanone (1).
4-acetoxymethylene-2-[2-benzyloxy-2-(5-methoxy-3-methylbenzo-cyclobuten-1-yl] ethyl-2-methylcyclopentan-1, 3-dione 1-ethylene ketal (21)热分解后得到了司他烷型四环化合物 (24),其脱酮化后得到了 26,这是一种潜在的槲皮苷 klaineanone (1) 合成中间体。