Synthetic Approach to Exo-Endo Cross-Conjugated Cyclohexadienones and Its Application to the Syntheses of Dehydrobrachylaenolide, Isodehydrochamaecynone, and <i>trans</i>-Isodehydrochamaecynone
作者:Yohsuke Higuchi、Fumito Shimoma、Rei Koyanagi、Kouji Suda、Tomokazu Mitsui、Takao Kataoka、Kazuo Nagai、Masayoshi Ando
DOI:10.1021/np0205250
日期:2003.5.1
Methodology for synthesis of exo-endo cross-conjugated dienones with trans- and cis-decalin systems has been reported. Bromination of the silyl enol ether of alpha'-methyl alpha,beta-unsaturated ketones with PTAB and successive dehydrobromination of the resulting alpha'-bromo-alpha'-methyl alpha,beta-unsaturated ketones under three conditions (DBU/PhH; TBAF/THF; Li(2)CO(3), LiBr/DMF) gave the desired
已经报道了用反式和顺式十氢化萘体系合成外-内交联二烯酮的方法。在三种条件下(DBU / PhH; TBAF / THF; Li(2)CO(3),LiBr / DMF)以良好的收率得到了所需的exo-endo交叉共轭二烯酮。该方法适用于从三叶草碱(7),查马西酮(5a)和反查马西酮(9)开始的脱氢布雷基内酯(1),异十二氢马西酮(5c)和反式异氢马西酮(11)的合成。拥有一个α-亚甲基γ-内酯部分(即1、7和13)的大马兜铃内酯 对细胞间粘附分子-1(ICAM-1)的诱导具有显着的抑制活性。化合物1的活性高于7和13。所有具有乙炔基的化合物5d,9、11和14均具有相同的杀蚁活性,并且11中的exo-endo交叉共轭二烯酮结构没有影响活动。