0000000000139836
AUTHOR
Abdessamad Debbab
showing 6 related works from this author
New bioactive alkaloids from the marine sponge Stylissa sp.
2012
Abstract Chemical investigation of the Indonesian marine sponge Stylissa species, which was collected at 2008 from Derawan Islands, Berau, NE Kalimantan, Indonesia offered four new brominated alkaloids, including 12-N-methyl stevensine (1), 12-N-methyl-2-debromostevensine (2), 3-debromolatonduine B methyl ester (3), 3-debromolatonduine A (4) together with eight known alkaloids identified as Z-hymenialdisine, Z-debromohymenialdisine, Stevensine, 2-debromostevensine, 3-bromoaldizine, 3,4-dibromopyrrole-2-carbamide, latonduine A, and latonduine B methyl ester (5–12), respectively. The structures of all isolated compounds were unambiguously elucidated based on extensive 1D and 2D NMR spectrosco…
Alkaloids from the Sponge-Associated FungusAspergillussp.
2012
Seven new alkaloids including tryptoquivaline K (1) and fumiquinazolines K–P (2–7), bearing a rare 1-aminocyclopropane-1-carboxylic acid residue, together with six known compounds (8–13), were isolated from the fungus Aspergillus sp. obtained from the Mediterranean sponge Tethya aurantium. The structures of the new compounds were determined by extensive analysis by 1D and 2D NMR spectroscopy and mass spectrometry. The absolute configurations of tryptoquivaline K (1) and fumiquinazolines K and L (2, 3) were determined by TDDFT ECD calculations of their solution conformers, and the configurational assignment of the related fumiquinazolines M–P (4–7) was achieved by comparison of their ECD spe…
Terpenoid bio-transformations and applications via cell/organ cultures: a systematic review.
2019
Structurally diverse natural products are valued for their targeted biological activity. The challenge of working with such metabolites is their low natural abundance and complex structure, often with multiple stereocenters, precludes large-scale or unsophisticated chemical synthesis. Since select plants contain the enzymatic machinery necessary to produce specialized compounds, tissue cultures can be used to achieve key transformations for large-scale chemical and/or pharmaceutical applications. In this context, plant tissue-culture bio-transformations have demonstrated great promise in the preparation of pharmaceutical products. This review describes the capacity of cultured plant cells t…
New Austalides from the Sponge-Associated Fungus Aspergillus sp.
2011
Chromatographic separation of a crude extract obtained from the fungus Aspergillus sp., isolated from the Mediterranean sponge Tethya aurantium, yielded five new meroterpenoid metabolites, austalides M–Q (1–5), together with nine known compounds (6–13). The structures of the new compounds were unambiguously elucidated on the basis of extensive 1D and 2D NMR methods and by mass spectral analysis. Furthermore, the absolute configurations of 1 and 4 were determined by time-dependent density functional theory electronic circular dichroism (TDDFT ECD) calculations, allowing the assignment of the absolute configuration of analogous compounds 2, 3, and 5. The calculations revealed that the conform…
A New Tetrahydrofuran Derivative from the Endophytic Fungus Chaetomium sp. Isolated from Otanthus maritimus
2009
1 A hitherto unidentified endophytic strain of the genus Chaetomium, isolated from the medicinal plant Otanthus maritimus, yielded a new tetrahydrofuran derivative, aureonitolic acid (), along with 5 known natural products, 2 - 6. The structure of 1 was determined by extensive spectroscopic analysis and comparison with reported data. Extracts of the fungus, grown either in liquid culture or on solid rice media, exhibited considerable cytotoxic activity when tested in vitro against L5178Y mouse lymphoma cells. Compounds 2 and 6 showed significant growth inhibition against L5178Y cells with EC50 values of 7.0 and 2.7 μg/mL, respectively, whereas 1 was inactive
Farinomalein derivatives from an unidentified endophytic fungus isolated from the mangrove plant Avicennia marina
2012
Five farinomalein derivatives including three new compounds, farinomaleins C–E (3–5), and one new isoindoline congener (6) were isolated from an unidentified endophytic fungus obtained from the inner tissues of healthy leaves of the mangrove plant Avicennia marina from Oman. The structures of the new compounds were unambiguously elucidated on the basis of their mass, as well as one and two dimensional NMR spectroscopic data.