Evaluation of Antimicrobial Activity of Some Compounds Isolated from Rhamnus cathartica L

A new anthraquinone derivative, 1,8-dihydroxy-2-[(z)-4-methylpenta-1,3-dien-1-yl] anthraquinone (1), together with known anthraquinone compounds were defined to be, 2-acetyl-3,8-dihydroxy-6-methoxyanthraquinone (2) , emodin (3), glucofrangulin A (4) and phenanthrene derivative named dendrochrysanene (5), lactone compounds named [-sorigenin (6) and geshoidin (7)], xanthone compound termed pruniflorone H (8), oxanthrone compound named rumejaposide I (9), flavonol compounds called [kaempferol (10) and quercetin (11)] have been isolated from the methanolic extract of Rhamnus cathartica L. All isolated compounds were obtained for the first time from the genus Rhamnus cathartica L. except emodin; they were subjected to antimicrobial activity test; compounds (1), (3), (9) exhibited antibacterial activity [G+ve, G-ve] and anti-yeast activity, whereas, compounds (5), (11) exhibited antibacterial activity [G+ve and G-ve]. But, compounds (2), (4), (7), (10) exhibited antibacterial activity G-ve while compounds (6), (8) exhibited antibacterial activity G-ve and anti-yeast activity. The isolated compounds were confirmed by detailed analysis of their 1H, 13CNMR, mass spectral data and by the results of hydrolytic cleavage.