Imidazole alkaloids from the indopacific sponge Pericharax heteroraphis

Chemical investigation of the sponge Pericharax heteroraphis [Polejeff] collected in Indonesia, has led to the isolation of three imidazole alkaloids, preclathridine-A [1], leucettamine-B [2] and leucettamine-A [3]. The structures of the isolated compounds were unambiguously established by [1]D and [2]D NMR and mass data. This is the first report of this class of compounds from the P. heteroraphis sponge. Investigation of the antimicrobial activities of the isolated compounds showed that leucettamin-A [3] was active against the gram-positive bacteria Staphylococcus aureus and the fungus Cladosporium herbarum, while other compounds were inactive

Minorris flavonoids and alkaloids from taverniera aegyptiaca biosis

From the acetone fraction of the methanol extract of the root bark of Taverniera aegyptiaca Boiss., seven isoflavones and a flavanol were isolated for the first time in the genus Taverniera viz. 7-methoxy, 4-hydroxy isoflavone; 6,7,4'-trimethoxy isoflavone; 6,4'-dimethoxy-hydroxy isoflavone; 6,7-dihydroxy-4-methoxy isoflavone; 6,7,4'-trihydroxy isoflavone; 6,4'-dimethoxy-7,3'-dihydroxy isoflavone; 6-methoxy, 7,3', 4'-trihydroxy isoflavone and 7-hydroxy flavanol. In addition, three alkaloids; namely, hippadine, pratorimine and 2-epilycorine, were characterized for the first time in Leguminosae. Identification of these compounds has been established by spectral techniques [UV, IR, MS, HRMS and 1H-NMR]