Flavonoids. 3. Studies on the synthesis of 2,4-dialkyl-7-acetoxy-4'-methoxy-delta-3-isoflavenes.
Flavonoids. 3. Studies on the synthesis of 2,4-dialkyl-7-acetoxy-4'-methoxy-delta-3-isoflavenes.
复制标题
DOI：
10.1021/jo01282a048
复制
发表时间：
1967-07
期刊：
影响因子：
--
通讯作者：
K. H. Dudley;R. C. Corley;H. W. Miller;M. Wall
中科院分区：
文献类型：
--
作者：
K. H. Dudley;R. C. Corley;H. W. Miller;M. Wall
描述了将2-甲基-7-四氢吡喃氧基-4'-甲氧基异黄酮转化为2,4-二烷基-7-乙酰氧基-4'-甲氧基-A3-异黄酮的方法。与烷基醚基团相比，四氢吡喃氧基的引入允许在合成的后期阶段轻松裂解保护基团（硼氢化物还原步骤所需）。合成步骤如下： 7-四氢吡喃氧基异黄酮—7-四氢吡喃氧基异黄烷醇-» 7-四氢吡喃氧基异黄烷酮—4-烷基-7-四氢吡喃氧基异黄烷醇—*·4-烷基-7-羟基-A3-异黄烯— 4-烷基-7-乙酰氧基-A3-异黄烯。本研究的目的是展示一种以游离酚或相应乙酸酯衍生物的形式获得2,4-二烷基-A3-异黄烯1的合成方法。 3 以前沿着这些路线进行的合成努力都受到低产率3或在合成的最终状态下发生不良反应的影响。 4
A method is described for the conversion of 2-methyl-7-tetrahydropyranyloxy-4'-methoxyisoflavone to 2, 4-dialkyl-7-acetoxy-4'-methoxy-A3-isoflavenes. The incorporation of the tetrahydropyranyloxy group, as contrasted with alkyl ether groups, permits a facile cleavage of the protecting group (required for the borohydride reduction step) at a later stage in the synthesis. The synthesis entails the steps: 7-tetrahydropyranyloxyisoflavone—7-tetrahydropyranyloxyisoflavanol-» 7-tetrahydropyranyloxyisoflavanone—4-alkyl-7-tetrahydropyranyloxy-isoflavanol—*· 4-alky l-7-hydroxy-A3-isoflavene— 4-alkyl-7-acetoxy-A3-isoflavene.The present study was commenced for the purpose of demonstrating a method of synthetic utility for obtaining 2, 4-dialkyl-A3-isoflavenes 1 in the form of free phenols or corresponding acetate derivatives. 3 Previous synthetic endeavors along these lines suffered from low yields3 or undesirable reactions at the final state of the synthesis. 4