[Chemical constituents from Hedyotis diffusa].

To investigate the chemical constituents from Hedyotis diffusa. The compounds were isolated and purified by various chromatographic techniques and identified by their physicochemical properties and spectral data. Eight compounds were isolated and identified as octadecyl (E)-p-coumarate (1), p-E-methoxy-cinnamic acid (2), ferulic acid (3), scopoletin (4), succinic acid (5), aurantiamide acetate (6), rubiadin (7), robustaquinone D (8). Compounds 1-8 were obtained from genus Hedyotis for the first time.