Clerodane Diterpenoids and Ecdysteroids From the Fruits of Tinospora sagittata (Oliv.) Gagnep.

Abstract

A new clerodane-type diterpenoid, tinosaginoside A (1), and two new ecdysteroids, tinosagisterones A and B (8 and 9), were isolated from the fruits of Tinospora sagittata (Oliv.) Gagnep., as well as and nine previously reported compounds (2-7 and 10-12). The structures and absolute configurations of 1, 8, and 9 were elucidated through comprehensive spectroscopic analyses, including two-dimensional nuclear magnetic resonance, high-resolution mass spectrometry, and infrared spectroscopy, as well as electronic circular dichroism calculations. Structurally, compound 8 is a rare ecdysteroid featuring a hexadienone unit, and 9 is an unprecedented ecdysteroid characterized by an oxygen bridge between C-2 and C-9. Additionally, compound 7 exhibited moderate inhibitory activity against nitric oxide production in lipopolysaccharide-induced RAW 264.7 cells, with an IC₅₀ value of 35.78 ± 0.37 µM, compared to the positive control, N^G-monomethyl-L-arginine, which had an IC₅₀ value of 40.28 ± 0.48 µM.