PHYTOCHEMICAL AND BIOLOGICAL INVESTIGATION OF CLEOME BRACHYCARPA VAHL. GROWING IN EGYPTAbstract
Flavonoid and sesquiterpene constituents of the aerial part of Cleome brachycarpa were chemically investigated and screened for their potential cytotoxicity. A flavonol glycoside; 3, 5, 4` trihydroxy-3`-methoxy flavone – 7 – O – a – L -rhamnopyranose (1“`® 2“) – O – β – D-glucopyranoside (1) and a megastigmane glucoside; (+)-(6S, 9R) roseoside (2) were isolated for the first time from the n-butanol fraction of the 90 % ethanol extract of Cleome brachycarpa. Four methylated flavonoids were isolated from the chloroform fraction and identified as 5,4`- dihydroxy-3,6,7,3′ tetramethoxyflavone (3), 5,5`- dihydroxy-3,6,7,3′,4′, pentamethoxy-flavone (4), 5-hydroxyl -3,6,7,3′,4′,5′-hexamethoxyflavone (5) and 5, 7,3′,4′ tetrahydroxyflavone (6) In addition, two sesquiterpene oxides, namely buchairol (7) and teucladiol (8) were isolated from the n-hexane fraction for the first time. Structure elucidation was achieved using spectroscopic techniques, including IR, UV, ESI-MS, EI-MS and 1D, and 2D-NMR. Each of the three fractions and isolated compounds were screened for their cytotoxicity and lethality using the brine shrimp (Artemia salina) assay. The results showed high lethality for all the examined samples, which might be very useful as antiproliferative and antitumor.