Assignment of Absolute Configuration of a New Hepatoprotective Schiartane-Type Nortriterpenoid Using X-Ray Diffraction.

A new schiartane-type nortriterpenoid, micrandilactone H was isolated from Kadsuralongipedunculata Finet et Gagnep. Its 2D (two dimension) structure was elucidated by NMR spectroscopic analysis, and it is similar to that of Kadnanolactones H and the absolute configuration was established through X-ray diffraction and ECD data analysis. This represents the first complete assignment of the absolute configuration of a schiartane-type nortriterpenoid by X-ray diffraction and the ECD method. Micrandilactone H showed moderate hepatoprotective activity against N-acetyl-p-aminophenol (APAP)-induced toxicity in HepG2 cells with cell survival rates of 56.84% at 10 μM.