Four New Cassane Diterpenoids From the Seeds of <i>Caesalpinia Mimosoides</i>

Four new cassane derivatives (1-4), along with five known compounds (5-9) were isolated from the seeds of Caesalpinia mimosoides. Their gross structures were elucidated by means of comprehensive spectroscopic analysis (ultraviolet, nuclear magnetic resonance, and high-resolution electrospray ionization mass spectrometry) as well as electronic circular dichroism calculations. Compounds 1-3 possessing norcassane-type skeleton were observed, which was a rare structural type in the Caesalpinia genus. The results of biological activity evaluation showed that compounds tested could inhibit the production of nitric oxide in lipopolysaccharide-induced RAW 264.7 cells, especially compound 8 exhibited excellent inhibitory activity, implying that these compounds may be potential anti-inflammatory candidates.