New Deoxyisoaustamide Derivatives from the Coral-Derived Fungus Penicillium dimorphosporum KMM 4689.

Seven new deoxyisoaustamide derivatives (1-7) together with known compounds (8-10) were isolated from the coral-derived fungus Penicillium dimorphosporum KMM 4689. Their structures were established using spectroscopic methods, X-ray diffraction analysis and by comparison with related known compounds. The absolute configurations of some alkaloids were determined based on CD and NOESY data as well as biogenetic considerations. The cytotoxic and neuroprotective activities of some of the isolated compounds were examined and structure-activity relationships were pointed out. New deoxyisoaustamides 4-6 at concentration of 1 µM revealed a statistical increase of PQ(paraquat)-treated Neuro-2a cell viability by 30-39%.

Neuroprotective Metabolites from Vietnamese Marine Derived Fungi of Aspergillus and Penicillium Genera.

Low molecular weight secondary metabolites of marine fungi Aspergillus flocculosus, Aspergillus terreus and Penicillium sp. from Van Phong and Nha Trang Bays (Vietnam) were studied and a number of polyketides, bis-indole quinones and terpenoids were isolated. The structures of the isolated compounds were determined by 1D and 2D NMR and HR-ESI-MS techniques. Stereochemistry of some compounds was established based on ECD data. A chemical structure of asterriquinone F (6) was thoroughly described for the first time. Anthraquinone (13) was firstly obtained from a natural source. Neuroprotective influences of the isolated compounds against 6-OHDA, paraquat and rotenone toxicity were investigated. 4-Hydroxyscytalone (1), 4-hydroxy-6-dehydroxyscytalone (2) and demethylcitreoviranol (3) have shown significant increasing of paraquat- and rotenone-treated Neuro-2a cell viability and anti-ROS activity.

Erylosides F8, V1-V3, and W-W2 - New triterpene oligoglycosides from the Carribean sponge Erylus goffrilleri.

Seven new triterpene glycosides, erylosides F8 (1), V1 (2), V2 (3), V3 (4), W (5), W1 (6) and W2 (7), were isolated from a Carribean sponge Erylus goffrilleri collected from the Carribean Sea near the Arrecife-Seco reef (Cuba). Structures of the glycosides were determined using 1H and 13C NMR spectroscopy, including 2D NMR procedures (1H-1H COSY, 1H-13С HMBC, 1H-13С HSQC and NOESY) and HR ESI mass spectrometry. Erylosides 1 and 4 have 14-carboxy-24,25-dimethyllanost-8(9)-en-3ß,25-diol as aglycone whereas glycosides 2, 3, 5, 6 and 7 are 14-carboxy-24-acetoxy-24-methyllanost-8(9)-en-3ß-ol glycoconjugates. Cytotoxic activities of the isolated compounds against Ehrlich carcinoma cells and hemolysis were examined and their dependence on eryloside structure was evaluated.

Isolation and structures of erylosides from the Caribbean sponge Erylus formosus.

Nine new triterpene glycosides, erylosides F1-F4 (1-4), M (5), N (6), O (7), P (8), and Q (9), along with previously known erylosides F (10) and H (11) were isolated from the sponge Erylus formosus collected from the Mexican Gulf (Puerto Morelos, Mexico). Structures of 1-4 were determined as the corresponding biosides having aglycons related to penasterol with additional oxidation patterns in their side chains. Erylosides 5-9 contain new variants of carbohydrate chains with three (5, 6), four (7), and six (8, 9) sugar units, respectively. Erylosides 5, 7, 8, and 6, 9 contain 14-carboxy-24-methylenelanost-8(9)-en-3beta-ol and penasterol as aglycons, respectively. In contrast with its epimer 2, the compound 3 induced the early apoptosis of Ehrlich carcinoma cells at a concentration of 100 microg/mL, while 1 and 10 activated the Ca2+ influx into mouse spleenocytes (130% of the control) at the same doses.