Isolation and characterization of bioactive phenolic compounds from Cinnamomum camphora barks

Two new phenolic rhamnosides (1-2) and 12 known phenolic compounds (3-14) were isolated from the ethanolic extract of Cinnamomum camphora barks by repeated column chromatography. The structures of all isolated compounds were identified by comprehensive spectroscopic data analysis such as high-resolution electrospray ionization mass spectra, nuclear magnetic resonance, optical rotatory dispersion and chemical method. In vitro assay revealed that compound 8 showed strong inhibitory activity against tyrosinase, and compounds 1, 3-7, 8-9, 13 showed obvious acetylcholinesterase inhibitory activity.