Search results for "Axinella"
showing 4 items of 4 documents
New Tetromycin Derivatives with Anti-Trypanosomal and Protease Inhibitory Activities
2011
Four new tetromycin derivatives, tetromycins 1-4 and a previously known one, tetromycin B (5) were isolated from Streptomyces axinellae Pol001(T) cultivated from the Mediterranean sponge Axinella polypoides. Structures were assigned using extensive 1D and 2D NMR spectroscopy as well as HRESIMS analysis. The compounds were tested for antiparasitic activities against Leishmania major and Trypanosoma brucei, and for protease inhibition against several cysteine proteases such as falcipain, rhodesain, cathepsin L, cathepsin B, and viral proteases SARS-CoV M(pro), and PL(pro). The compounds showed antiparasitic activities against T. brucei and time-dependent inhibition of cathepsin L-like proteas…
Damipipecolin and damituricin, novel bioactive bromopyrrole alkaloids from the Mediterranean sponge Axinella damicornis
2007
Two new bromopyrrole alkaloids, damipipecolin (1) and damituricin (2), have been isolated from the Mediterranean sponge Axinella damicornis, and their structures established through spectroscopic methods. Compounds 1 and 2 extend the structural variety of the so far known pyrrole alkaloids; in these compounds, the 4-bromopyrrole 2-carboxylic acid is directly condensed with a non-protein cyclic alpha-amino acid, the (2R, 4R)-trans-4-hydroxypipecolic acid and (2R, 4R)-cis-N,N'-dimethyl-4-hydroxyproline (D-turicine) in 1 and 2, respectively. Compounds 1 and 2 were found to display a modulating effect of the serotonin receptor activity in vitro.
Cycloamphilectenes, a new type of potent marine diterpenes: inhibition of nitric oxide production in murine macrophages.
2003
The inhibitory effect of a series of 6 cycloamphilectenes, novel marine diterpenes based on amphilectene skeletons and isolated from the Vanuatu sponge Axinella sp., on NO, PGE(2) and TNFalpha production in murine peritoneal macrophages was studied. These compounds reduced potently nitric oxide production in a concentration-dependent manner with IC(50) values in the submicromolar range (0.1-4.3 microM). Studies on intact cells and Western blot analysis showed that the more potent cycloamphilectenes reduced the expression of inducible nitric oxide synthase without affecting cyclo-oxygenase-2 expression. Among them cycloamphilectene 2, the unique compound bearing an exocyclic methylene group,…
Novel bioactive bromopyrrole alkaloids from the Mediterranean sponge Axinella verrucosa
2005
The Mediterranean sponge Axinella verrucosa has been investigated for its alkaloid composition and has been found to produce a complex mixture of bromopyrrole alkaloids. Along with the previously isolated compounds 5-18, four novel alkaloids of this class, compounds 1-4, have been isolated, and their structures established through spectroscopic methods. Compounds 1-4 were found to display neuroprotective activity against the agonists serotonin and glutamate in vitro.