Cassane diterpenoids from <i>Caesalpinia pulcherrima</i> and their anti-inflammatory and <i>α</i> -glycosidase inhibitory activities
Xin Yun, Xiu‐Mei Chen, Jiayun Wang, Lu Wang, Zi‐Han Zhang, Young Ho Kim, Shuwan Zong, Chun‐Huan Li, Jin‐Ming Gao
Abstract
Three undescribed cassane-type diterpenoids (CAs), caesalpulcherrins K-M (1–3), together with three known ones (4–6) were isolated from the aerial parts of Caesalpinia pulcherrima (L.) Sw (Fabaceae). Their structures were elucidated via analysis of NMR (1 D and 2 D) and HRESIMS data. The character for caesalpulcherrin K possessing the olefin bond at C-11 and C-12 in its cassane skeleton was observed, which belonged to a small group among more than 450 CAs. That is, only fifteen derivatives have been reported up to now, to our knowledge. Biological evaluation revealed that compounds 1–6 exhibited moderate anti-inflammatory activity, with an IC50 value from 6.04 ± 0.34 to 8.92 ± 0.65 μM. Furthermore, compounds 5 and 6 exhibited significant α-glucosidase inhibitory activity at 10 μM.