Abstract: Chemical investigation of the root of Alchornea trewioides led to the isolation of 9 compounds by silica gel and Sephadex LH-20 column chromatography methods,their structures were elucidated as squalene (1),acetyl aleuritolic acid (2),friedelin (3),methyl-3-acetoxy-12-oleanen-28-oate (4),maslinic acid (5),methyl maslinate (6),β-sitosterol (7),β-sitosterol-3-O-stearate (8),and stigmasta-4-ene-3,6-dione (9) on the basis of spectroscopic analyses.Compounds 2,3 and 7 were isolated from the plant for the first time,and other compounds were isolated from the genus Alchornea for the first time.The PTP1B inhibitory activity was evaluated for the compounds isolated from the plant,compounds 2,5,6,and 8 showed PTP1B inhibitory activity.

Key words: Alchornea trewioides, chemical constituents, triterpenes, PTP1B