Flavones and Cytotoxic Constituents from the Stem Bark of Muntingia calabura

摘要

Two new flavones,8-hydroxy-7,3',4',5'-tetramethoxyflavone and 8,4'-dihydroxy-7,3'',5'-trimethoxy-flavone,together with thirteen known compounds have been isolated from the stem bark of Muntingia calabura.The structures of two new compounds were determined through spectral analyses.Among the isolates,8-hydroxy-7,3',4',5'-tetramethoxyflavone,8,4'-dihydroxy-7,3',5'-trimethoxyflavone,and 3-hydroxy-l-(3,5-dimethoxy-4-hydroxyphenyl)propan-l-one exhibited effective cytotoxicities (ED_(50) values=3.56,3.71,and 3.27 ng/mL,respectively) against the P-388 cell line in vitro.