Anticomplement cycloartane triterpene glycosides from Beesia calthaefolia (Maxim.)

Abstract Investigation of the n -BuOH extract of the whole plant of Beesia calthaefolia led to the isolation of three new cycloartane triterpenoids ( 1–3 ) and two known compounds ( 4, 5 ). Their structures were elucidated by 1D and 2D NMR, HRESIMS and optical rotation spectral data. All of the isolates were investigated for their inhibitory effects on the classical pathway of the complement system. Among them, compound 3 showed stronger inhibitory activity (IC 50 148.0 μM) than the positive control (rosmarinic acid, IC 50 181.8 μM), while other compounds ( 1 , 2 , 4 and 5 ) showed moderate activity. The chemical compound studied in this article was rosmarinic acid (PubChem CID: 5281792).