A multifunctional oxidosqualene cyclase from Tripterygium regelii that produces both α- and β-amyrin

A multifunctional oxidosqualene cyclase was cloned from Tripterygium regelii and identified as a mixed-amyrin synthase, which can produce both α- and β-amyrin.

Dimacrolide Sesquiterpene Pyridine Alkaloids from the Stems of Tripterygium regelii

Two new dimacrolide sesquiterpene pyridine alkaloids (DMSPAs), dimacroregelines A (1) and B (2), were isolated from the stems of Tripterygium regelii. The structures of both compounds were characterized by extensive 1D and 2D NMR spectroscopic analyses, as well as HRESIMS data. Compounds 1 and 2 are two rare DMSPAs possessing unique 2-(3′-carboxybutyl)-3-furanoic acid units forming the second macrocyclic ring, representing the first example of DMSPAs bearing an extra furan ring in their second macrocyclic ring system. Compound 2 showed inhibitory effects on the proliferation of human rheumatoid arthritis synovial fibroblast cell (MH7A) at a concentration of 20 μM.