Abstract: Two new compounds, 1-(3-methoxy-4-hydroxyphenyl)-3-(3, 5-dimethoxy-4-hydroxyphenyl)-propane (1) and 5, 7, 3''-trimethyoxyflavan-4''-O-β-D-glucopyranoside (2) were isolated from the ethanol extract of the dried aerial parts of Phacellaria compressa Benth., together with 2,3-bis[(4-hydroxy-3,5-dimethoxyphenyl)-methyl]-1,4-butanediol (3), ethyl 3,4,5-trihydroxybenzoate (4), methyl 3, 4, 5-trihydroxybenzoate (5),β-sitosterol (6), 5, 7, 3'', 4''-tetrahydroxyflavan (7), lupeol (8), zhebeiresinol (9), quercetin-3-O-α-L-rhamnopyranoside (10), (+)-catechin (11), betulin (12), β-daucosterol (13), (+)-syringaresinol (14), scopoletin (15), and proximadiol (16). The structures of these compounds were determined by spectral evidence or by comparing them with authentic samples. Compound 9 showed α-amylase inhibitory activity of 57.55% at a concentration of 50 μg/mL.

Key words: α-amylase, 1,3-diphenyl-propane, flavan-4''-O-β-D-glucopyranoside, Phacellaria compressa.