Anti-Helicobacter pylori and thrombin inhibitory components from Chinese Dragon's blood, Dracaena cochinchinensis

Chemical studies on the constituents of Dracaena cochinchinensis led to the discovery of eight new flavonoid derivatives (1-8) along with 14 known compounds (9-22). The identification and structural elucidation of these isolates were based on spectral analyses. All isolates were tested for antibacterial activities against Helicobacter pylori (ATCC43504) and thrombin inhibitory effects. As a result, new flavonoid derivatives 6 and 7 and (2S)-4',7-dihydroxy-8-methylflavan (11) were found to be most efficacious against H. pylori (ATCC43504) with MIC values of 29.5, 29.5, and 31.3 mu M, respectively, and the seven new flavonoid derivatives (1-7) and one known biflavonoid (9) were observed to exhibit moderate thrombin inhibitory activity.