Publications by authors named "Linh H Mai"

Thirteen nitrogen-containing molecules (/ and -) were isolated from the Indonesian sponge , highlighting the richness of this organism as a source of alkaloids. Their structures were elucidated using one- and two-dimensional NMR spectroscopy and HR-ESI-MS, while the stereochemistry of the diketopiperazines was established using Marfey's method. All compounds were screened in our standard bioactivity assays, including antibacterial, antikinases, and amyloid β-42 assays.

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The rapid emergence of resistant bacteria during the last 20 years has stimulated research efforts in order to overcome this thorny problem. Marine sponges and their associated bacteria, which have been proven to be a source of bioactive natural products, have appeared as a promising opportunity to identify new antibiotic compounds. An overview of the major antibacterial compounds isolated from marine sponges and/or their associated bacteria is presented in this chapter, highlighting new potential antibiotics.

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The halogenated alkaloid chloromethylhalicyclamine B (1), together with the known natural compound halicyclamine B (2), was isolated from the extract of the sponge Acanthostrongylophora ingens. The structure of compound 1 was determined by spectroscopic means, and it was shown that 1 is produced by reaction of 2 with CHCl used for extraction. Compound 1 was a selective CK1δ/ε inhibitor with an IC of 6 μM, while the natural compound 2 was inactive.

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Seven new adociaquinone derivatives, xestoadociaquinones A (1a), B (1b), 14-carboxy-xestoquinol sulfate (2) and xestoadociaminals A-D (3a, 3c, 4a, 4c), together with seven known compounds (5-11) were isolated from an Indonesian marine sponge Xestospongia sp. Their structures were elucidated by extensive 1D and 2D NMR and mass spectrometric data. All the compounds were evaluated for their potential inhibitory activity against eight different protein kinases involved in cell proliferation, cancer, diabetes and neurodegenerative disorders as well as for their antioxidant and antibacterial activities.

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A series of 16 flavonoids were isolated and prepared from bud exudate of Gardenia urvillei and Gardenia oudiepe, endemic to New Caledonia. Most of them are rare polymethoxylated flavones. Some of these compounds showed noticeable activity against Leishmania (Leishmania) amazonensis, Plasmodium falciparum and Trypanosoma brucei gambiense, in addition to tubulin polymerization inhibition at low micromolar concentration.

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