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The synthesis of fradcarbazole A (I) and its phenyl and oxazole analogues involves a biomimetic intramolecular cyclization/dehydration.

Isolation and structural characterization of four new acyclic bipyridine glycosides, cyanogrisides E (Ia), F (Ib), G (IIa), and H (IIb) are described.

Cyanogramide (1), an unprecedented alkaloid bearing a novel spirocyclic pyrrolo[1,2-c]imidazole skeleton, was identified from the fermentation broth of the marine-derived Actinoalloteichus cyanogriseus WH1-2216-6. The structure was fully determined by spectroscopic analysis, an exciton chirality CD method, and quantum mechanical calculations. Cyanogramide (1) could efficiently reverse the adriamycin-induced resistance of K562/A02 and MCF-7/Adr cells, and the vincristine-induced resistance of KB/VCR cells at a concentration of 5 μM, with the reversal fold values of 15.5, 41.5, and 9.7, respectively.

The new cytotoxic bispyrrolidinoindoline diketopiperazine alkaloid cristatumin E (I) shows weak antibacterial activity against E.

Based on the total syntheses of all eight possible stereoisomers the previously reported structures of versicolactones A (I) and B (II) are reassigned.

The title compound is synthesized by addition of V2O5 dissolved in sodium carbonate solution to an aqueous solution containing Na3PO4 and Na2WO4 (pH 2.5, 90 °C, 2 h).

Penispirolloid A (1), a novel alkaloid possessing a unique Spiro imidazolidinyl skeleton, was isolated from a halotolerant fungal strain. Penicillium sp. OUCMDZ-776. Its structure was elucidated on the basis of spectroscopic methods and quantum chemical CD calculation. Compound 1 showed significant antifouling activity toward Bugula neritina larvae with EC50 of 2.40 mu g/ml. Plausible biogenesis of compound 1 was also proposed. (C) 2012 Elsevier Ltd. All rights reserved.

The new indole derivative (I) is isolated along with two known compounds from the ethyl acetate extract of Aspergillus sclerotiorum PT06-1 in a hypersaline nutrient-rich medium.

The novel quinazolinone alkaloids (I) and (II) are isolated along with seven known analogues from the BuOH extract of the marine-derived bacterium Bacillus cereus.

The new solid high-proton conductor H7P2W17VO62·28H2 O is obtained from an aqueous HCl solution of NaVO3 and K10P2W17O61 and characterized by XRD, TG/DTA, IR, UV, and electrochemical impedance spectroscopy.

The structures of the new cottoquinazolines B (Ia), C (Ib), and D (Ic) are determined by spectroscopic means, X-ray analysis, and chemical transformation.

Aqueous potassium peroxymonosulfate oxidizes water-immiscible alkenes at room temperature in the absence of organic solvent. Acidic (pH I 1.7) solutions of 2KHS05-KHS04.K2S04 in water produced the epoxide from cyclooctene and diols from all other reactive alkenes investigated. Adjustment of initial pH to 1 6.7 with NaHC03 enabled selective epoxidations of 2,3-dimethyl-2-butene, 1-methylcyclohexene, cyclohexene, styrene, and 8methylstyrene. The order of decreasing reactivity of alkenes was: 2,3-dimethyl-2-butene > 1-methylcyclohexene 2 cyclohexene > cyclooctene,> a-methylstyrene 1 @-methylstyrene > styrene > p-methylstyrene > allylbenzene. 1-Octene and tetrachloroethylene did not react. Phaset rader catalysts, a colloidal cationic polymer, and a cationic surfactant microemulsion had little effect on the reaction.

Eleven atisine-type diterpene alkaloids, including five new ones 19-O-deethylspiramine N (1), 15-deacetylspiramine S (2), spiramine Z-2 (3), spiramine Z-3(4), deacetylspiramine F(5), and six known ones, spiramines A, B, C, D, F(6), H were isolated from the air dried Spiraea japonica var. ovalifolia.

14-alpha-Deoxyecdysteroids were obtained in an isolated yield of 50% by the one step reduction of 20-hydroxyecdysone with activated Zn powder in anhydrous acetic acid at 65-70degreesC. About 24% isolated yields of the 14-beta-deoxyecdysteroid were also obtained.

Pennicitrinone D, a new citrinin dimer from the halotolerant fungus Penicillium notatum B-52

Chrysogenamide A (1), a new member of the macfortine group of alkaloids, along with four known compounds (2 approximately 5) were identified from Penicillium chrysogenum No. 005, an endophytic fungus associated with Cistanche deserticola Y. C. Ma. The new structure was elucidated on the basis of comprehensive spectral analysis. 1 exhibited a neurocyte protection effect against oxidative stress-induced cell death in SH-SY5Y cells.

A new diketopiperazine alkaloid containing the uncommon amino acid L-7, 9-dihydroxy-8-methoxyphenylalanine (1), has been isolated from the algicolous Aspergillus flavus strain. The structure of 1 including the absolute stereochemistry was determined by spectroscopic data and chemical means. Compound 1 showed weak cytotoxicity against HL-60 cell lines with an IC50 value of 36.5 microg/ml.

Four polyketides, leptosphaerone C (1), penicillenone (2), arugosin I (3) and 9-demethyl FR-901235 (4), as well as five known compounds, bacillosporin A (5), bacillosporin C (6), sequoiamonascin D (7), sequoiatone A (8), and sequoiatone B (9) were isolated from the Penicillium sp. JP-1, an endophytic fungus isolated from Aegiceras corniculatum. Their structures were determined by spectroscopic methods, mainly by 2D NMR spectroscopic analyses. Compound 1 showed cytotoxicity against A-549 cells with an IC50 value of 1.45 μM, while compound 2 showed cytotoxicity against P388 cells with an IC50 value of 1.38 μM.

Two new quinone type compounds, variecolorquinones A (1) and B (2) together with eleven known related compounds 3∼13 have been isolated from the metabolites produced by the halotolerant fungal strain Aspergillus variecolor B-17. The structures of 1 and 2 were determined by spectroscopic methods. 1 exhibited selective cytotoxicity against A-549 cells with the IC50 values of 3.0 μM. 2 showed cytotoxicity against HL60 and P388 cells with the IC50 values of 1.3 and 3.7 μM, respectively.

Two new secondary metabolites, carbonarones A (1) and B (2), were obtained from the culture of the marine-derived fungus Aspergillus carbonarius isolated from the marine sediment collected at Weizhou island of China. Based on ESIMS, 1D and 2D NMR data, and the X-ray crystallographic analysis, their structures were elucidated as 6-benzyl-4-oxo-4H-pyran-3-carboxamide and 6-benzyl-4-hydroxy-2-oxo-1, 2-dihydropyridine-3-carbaldehyde, respectively. 1 and 2 showed moderate cytotoxicity against K562 cells with IC(50) values of 56.0 and 27.8 mug/ml, respectively.

A new diphenyl ether dimethyl 2,3'-dimethylosoate (1) together with three known compounds monomethylsulochrin (2), emodin (3), and questin (4) were isolated through bioassay-guided fractionations from the culture of a marine-derived fungus Aspergillus sp. B-F-2. The structures of these compounds were determined by spectroscopic methods. Cytotoxicities of compounds 1 and 2 against K562 cell line were preliminarily evaluated by the MTT method and flow cytometry.

Four new compounds were isolated from a marine-derived fungus Penicillium terrestre, namely 2-(2', 3'-dihydrosorbyl)-3,6-dimethyl-5-hydroxy-1,4-benzoquinone (1), 3-acetonyl-2,6-dimethyl-5-hydroxy-1,4-benzoquinone (2), dihydrobisvertinolone (3), tetrahydrobisvertinolone (4). Their structures were established on the basis of spectroscopic methods. The absolute configurations of 3 and 4 were determined by their CD spectra. Their cytotoxic effects on P388 and A-549 cell lines were preliminarily examined by the MTT method.