Chemical constituents of Carya cathayensis and their antitumor bioactivity

Objective: To investigate the chemical constituents of Carya cathayensis and their antitumor bioactivity.Methods: The compounds were isolated by Sephadex LH-20 and silica gel column chromatography.Their structures were identified by physicochemical properties and spectroscopic analysis.Then their cytotoxic activity was studied.Results: Five compounds were elucidated as chrysophanol(1),physcion(2),β-sitosterol(3),pinostrobin(4),4,8-dihydroxy-1-tetralone(5).Conclusion: Compounds 2 and 5 are isolated from Carya cathayensis for the first time.In the MTT antitumor experiments,the compounds 1,4 and 5 have the cytotoxic activity to KB cell.