Six New Methyl Apiofuranosides from the Bark of Phellodendron chinense Schneid and Their Inhibitory Effects on Nitric Oxide Production

A chemical investigation on 70% EtOH extract from the bark of Schneid (Rutaceae) led to six new methyl apiofuranosides ( - ), and ten known compounds ( - ). All these compounds were characterized by the basic analysis of the spectroscopic data including extensive 1D-, 2D-NMR (HSQC, HMBC), and high-resolution mass spectrometry, and the absolute configurations were determined by both empirical approaches and NOESY. Inhibitory effects of compounds - and - on nitric oxide production were investigated in lipopolysaccharide (LPS)-mediated RAW 264.7 cells, as a result, most of these isolates inhibited nitric oxide (NO) release, and among them , and displayed the strongest inhibition on NO release at the concentration of 12.5 μM.