0000000001302125

AUTHOR

Heidrun Anke

Isolation, structure elucidation, and biological evaluation of the unusual heterodimer chrysoxanthone from the ascomycete IBWF11-95A

Chrysoxanthone, an unusual heterodimer of blennolide A and 2-hydroxychrysophanol linked through a diaryl ether bridge, was isolated from mycelia of the ascomycete IBWF11-95A grown in submerged culture. Its structure was elucidated by two-dimensional NMR spectroscopy. The metabolite shows antibacterial activity against different species with MIC values between 2.5 and 20 μg/mL while also inhibiting the growth of several fungi.

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Omphalotins E-I, Five Oxidatively Modified Nematicidal Cyclopeptides fromOmphalotus olearius

Omphalotins E–I, oxidatively modified cyclic dodecapeptides, were isolated from mycelial extracts of the basidiomycete Omphalotus olearius, and their structures were determined by NMR spectroscopic and MS methods. Four of the five omphalotins contained an unprecedented N-hydroxylated tricyclic tryptophan derivative. All compounds exhibited strong and selective nematicidal activity against the plant pathogen Meloidogyne incognita with LD90 values between 2 and 5 μg mL–1. Cytotoxic activities were not detected up to 50 μg mL–1. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

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GKK1032A2, a secondary metabolite from Penicillium sp. IBWF-029-96, inhibits conidial germination in the rice blast fungus Magnaporthe oryzae

GKK1032A 2 , a secondary metabolite from Penicillium sp. IBWF-029-96, inhibits conidial germination in the rice blast fungus Magnaporthe oryzae

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Coumarin derivatives from Pedilanthus tithymaloides as inhibitors of conidial germination in Magnaporthe oryzae

In a screening for inhibitors of infection-related morphogenesis in the rice blast fungus Magnaporthe oryzae, a series of 10 coumarin derivatives were isolated from Pedilanthus tithymaloides (Euphorbiaceae). Seven of these compounds turned out to be known while three represent previously unreported natural products. Their structures were established on the basis of spectroscopic data and X-ray crystallography. Nine out of 10 coumarin derivatives were found to inhibit conidial germination in the phytopathogenic fungus at low concentrations.

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ChemInform Abstract: Sterelactones: New Isolactarane Type Sesquiterpenoids with Antifungal Activity from Stereum sp. IBWF 01060.

Four members of a new family of tetracyclic sesquiterenoids possessing the isolactarane skeleton have been isolated from mycelial cultures of Stereum sp. IBWF 01060. Their structure elucidation and their antifungal activity against several plant pathogens as well as other microorganisms are reported.

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Drimane Sesquiterpenoids from Marasmius sp. Inhibiting the Conidial Germination of Plant-Pathogenic Fungi

From the basidiomycete Marasmius sp., strain IBWF 96046, three new sesquiterpenoids based on the drimane skeleton were isolated and named marasmene B and marasmals B and C. In this study, their isolation, structure elucidation, and biological evaluation are described. The compounds have a pronounced inhibitory effect on the conidial germination of several plant-pathogenic fungi.

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ChemInform Abstract: Omphalotins E-I, Five Oxidatively Modified Nematicidal Cyclopeptides from Omphalotus olearius.

Omphalotins E–I, oxidatively modified cyclic dodecapeptides, were isolated from mycelial extracts of the basidiomycete Omphalotus olearius, and their structures were determined by NMR spectroscopic and MS methods. Four of the five omphalotins contained an unprecedented N-hydroxylated tricyclic tryptophan derivative. All compounds exhibited strong and selective nematicidal activity against the plant pathogen Meloidogyne incognita with LD90 values between 2 and 5 μg mL–1. Cytotoxic activities were not detected up to 50 μg mL–1. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)

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Sterelactones: New Isolactarane Type Sesquiterpenoids with Antifungal Activity from Stereum sp. IBWF 01060

Four members of a new family of tetracyclic sesquiterenoids possessing the isolactarane skeleton have been isolated from mycelial cultures of Stereum sp. IBWF 01060. Their structure elucidation and their antifungal activity against several plant pathogens as well as other microorganisms are reported.

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CCDC 861603: Experimental Crystal Structure Determination

Related Article: Louis P. Sandjo, Andrew J. Foster, Joachim Rheinheimer, Heidrun Anke, Till Opatz, Eckhard Thines|2012|Tetrahedron Lett.|53|2153|doi:10.1016/j.tetlet.2012.02.056

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