Cassan Diterpenoids with Cav3.1 T-type Calcium Channel Inhibitory Activity from the Seeds of Caesalpinia decapetala (Roth) Alston.

Abstract

Phytochemical investigation of the 80% ethanol extract from the seeds of Caesalpinia decapetala (Roth) Alston led to the identification of nine compounds, which included three new cassane-type diterpenoids, caesalpideplins A-C (1-3), and six known analogues (4-9). The structures of 1-3 were determined using a comprehensive analytical method that involved detailed IR, HRESIMS, 1H, 13C, and 2D NMR analyses. The absolute configuration of 1 was established through X-ray single crystal diffraction analysis, while the absolute configurations of 2 and 3 were determined by comparing their calculated and experimental ECD data. Additionally, compounds 3, 4, 5, 7, and 8 demonstrated notable inhibitory activity against the Cav3.1 T-type calcium channel with IC50 values of 23.13, 9.46, 29.53, 34.02, and 24.33 μM, respectively. These results suggest that cassane-type diterpenoids may have potential therapeutic applications for diseases related to the Cav3.1 calcium channel.