树豆内酯A粗品皂化产物的化学结构鉴定

Structural Identification on the Saponification Products of Raw Cajanolactone A

摘要:

对天然产物树豆内酯A进行皂化反应以期获得具有降血糖、降血脂活性的天然药物先导物树豆酮酸A。利用含有树豆内酯A和球松素各约50%的粗品，经0.65% KOH含水乙醇回流3.5 h皂化，产物经柱层析分离纯化获得皂化产物；通过理化和波谱学分析鉴定产物的化学结构。分离并鉴定了全部5个皂化产物，除了预期产物树豆酮酸A以外，其余4个低得率的副产物结构分别为1-（2，6-二羟基-4-甲氧基苯基）乙酮（2）、球松素查尔酮（3）、cajanotone（4）和1个新化合物（1），化合物1鉴定为CAA的异构体，命名为树豆酮酸B（Cajanonic acid B）。这为进一步研究开发树豆（Cajanus cajan）叶生物活性成分提供了新的实验依据。

Abstract:

The aim of this work was to obtain a natural hypoglycemic and hypolipidemic drug lead cajanonic acid A (CAA) by saponification of a natural product cajanolactone A (CLA). A mixture containing about both 50% amount of CAA and pinostrobin was treated with 0.65% KOH in aqueous ethanol for 3.5 h under reflux, the mixed products were isolated through column chromatography and identified by physico-chemical and spectroscopic analysis. Besides the expected product CAA, four minor saponificative products were obtained, and identified as 1-(2,6-dihydroxy-4-methoxyphenyl)-ethanone (2), pinostrobin chalcone (3), cajanotone (4), and compound 1. Compound 1, a structural isomer of CAA, was found to be a new compound and named as cajanonic acid B. These would provide a new experimental basis for the further research and development bioactive component of Cajanus cajan leaves.