3-羰基-10-去甲基-12-甲氧基-13-甲基罗汉松烷的全合成

Total Synthesis of 3-Carbonyl-10-demethyl-12-methoxy-13-methyl-podocarpene

以1,3-环己二酮为原料,经过甲基化反应和羰基保护构筑了A环合成子(5)。以邻甲基苯甲醚为原料,对位溴代、与环氧乙烷加成和进一步溴代等反应合成了C环合成子(9)。化合物5与9的格氏试剂偶联和关环反应完成目标产物3-羰基-10-去甲基-12-甲氧基-13-甲基罗汉松烷(11)的全合成。各中间体及目标产物结构均经红外光谱、核磁、质谱等表征,结果表明,成功实现了目标产物的合成。

A-ring synthon 5 was synthesized from 1,3-cyclohexanedione via methylation and carbonyl protection.C-ring synthon 9 was synthesized from 1-methoxy-2-methylbenzene by means of bromination,the addition of ethylene epoxide and further bromination.Compound 5 reacted with Grignard reagent of 9 followed by cyclozation to afford target molecule 11.All intermediates and target product were confirmed by IR,^1H NMR and HRMS.In conclusion,a simple synthetic route has been developed and the target molecule has been successfully synthesized.