Department of Life and Environmental Sciences , University of Cagliari , 09124 Cagliari , Italy.
R. C. Patel Institute of Pharmaceutical Education and Research , Shirpur , 425404 India.
J Nat Prod. 2019 May 24;82(5):1250-1257. doi: 10.1021/acs.jnatprod.8b01023. Epub 2019 Apr 18.
Nine compounds, including two undescribed withanolides, withasomniferolides A and B (1 and 2), three known withanolides (3-5), a ferulic acid dimeric ester (6), and an inseparable mixture of three long alkyl chain ferulic acid esters (7-9), were isolated from a GABA receptor positive activator methanol extract of the roots of Withania somnifera. The structures of the isolated compounds were elucidated based on NMR, MS, and ECD data analysis. In order to bioassay the single ferulic acid derivatives, compounds 6-9 were also synthesized. The most active compound, docosanyl ferulate (9), was able to enhance the GABA receptor inhibitory postsynaptic currents with an IC value of 7.9 μM. These results, by showing an ability to modulate the GABA receptor function, cast fresh light on the biological activities of the secondary metabolites of W. somnifera roots.
从茄科植物睡茄的根的 GABA 受体阳性激活物甲醇提取物中分离得到了 9 种化合物，包括 2 种未描述的茄属生物碱，即睡茄酮 A 和 B（1 和 2）、3 种已知的茄属生物碱（3-5）、1 种阿魏酸二聚酯（6）和 1 种不可分离的 3 种长链烷基阿魏酸酯混合物（7-9）。基于 NMR、MS 和 ECD 数据分析，鉴定了分离化合物的结构。为了对单一阿魏酸衍生物进行生物测定，还合成了化合物 6-9。最活跃的化合物二十二烷酸酯（9）能够增强 GABA 受体抑制性突触后电流，IC 值为 7.9 μM。这些结果表明，它能够调节 GABA 受体功能，为睡茄根的次生代谢物的生物学活性提供了新的线索。
