ZHAO Jian-yang1,2, WANG Ting1,2, LIU Qing-qing1,2,ZHU Jin1, HUANG Qing-fei1, WANG Qi-wei1
1. Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, China; 2. University of Chinese Academy of Sciences, Beijing 100049, China
Abstract:A novel method for the synthesis of the ginkgolic acid was reported. 2-Methoxy-6-tridec-1-enylbenzoic acid methyl este(6a) and 2-methoxy-6-pentadec-1-enylbenzoic acid methyl ester(6b) were synthesized by methlation, N-bromosuccinimide substitution and constructing different long chain olefins via Wittig reaction from 2-methy-5-hydroxy benzoic acid. Two ginkgolic acids with different long chains were synthesized by reduction of carbon carbon double bond of 6 with palladium carbon then demethylating, the total yield were 46% and 40%, respectively. The structures were confirmed by 1H NMR and ESI-MS.