Abstract
The phytochemical investigation of the ethyl acetate soluble fraction of the dried floral buds of Syringa patula palibiniana Nakai (Oleaceae) has led to the isolation of six compounds: β-amyrin acetate (1), β-sitosterol (2), nortropin (3), eugenol (4), syringaresinol (5), and oleoside 11-methyl ester (6). The structures were elucidated by spectroscopic and chemical means. Investigation of the biological activities indicated that 5 and 6 possessed a strong cytotoxic activity against Hep-G2 cells; 1 and 5 remarkably increased the macrophage proliferation index; 1 and 5 exhibited high anti-inflammatory activities as indicated by inhibited LPS-induced NO generation; and only 5 showed a strong scavenging activity against DPPH. Taken together, results indicate that 5 is a multipotent compound active as an anti-cancer, immunoproliferative, anti-inflammatory, and antioxidant agent.