Three minor microcystins have been isolated from a Planktothrix rubescens strain.Their structures have been elucidated by one-and two-dimensional NMR spectroscopy and high-resolution tandem mass spectrometry as the co...Three minor microcystins have been isolated from a Planktothrix rubescens strain.Their structures have been elucidated by one-and two-dimensional NMR spectroscopy and high-resolution tandem mass spectrometry as the compounds[Asp^(3),(E)-Dhb^(7)]MC-LY(1),[Asp^(3),(E)-Dhb^(7)]MC-HtyW(2),and[Asp^(3),(E)-Dhb^(7)]MC-LW(3).The amino acids found at the variable positions 2 and 4 of the microcystin core structure are in accordance with the predicted amino acid substrate activation selectivities of the non-ribosomal peptide synthetases McyA and McyB described earlier for this strain.All structural microcystin variants produced by this strain were shown to inhibit protein phosphatase 1 in the nanomolar range.展开更多
Two farnesylhydroquinones were isolated from the fruiting bodies of Ganoderma pfeifferi,farnesylhydroquinone(1)and the new compound ganomycin K(2),(5S)-3-[(E)-7,8-dihydroxy-4,8-dimethylnon-3-enyl]-5-(2,5-dihydroxyphen...Two farnesylhydroquinones were isolated from the fruiting bodies of Ganoderma pfeifferi,farnesylhydroquinone(1)and the new compound ganomycin K(2),(5S)-3-[(E)-7,8-dihydroxy-4,8-dimethylnon-3-enyl]-5-(2,5-dihydroxyphenyl)-furan-2(5H)-one.The structures of 1 and 2 were determined on the basis of mass spectrometric and NMR spectroscopic evidence.The antibacterial activity of the isolated compounds was neglectable.展开更多
基金supported by the German Federal Ministry of Economics and Technology(KF2766301SB0)the Leibniz-Institut fur Molekulare Phamakologie(FMP),the Austrian Science Fund(P24070)the Austrian Climate Research Program(ACRP)project RADICAL(Risk Analysis of Direct and Indirect Climate effects on deep Austrian Lake Ecosystems).
文摘Three minor microcystins have been isolated from a Planktothrix rubescens strain.Their structures have been elucidated by one-and two-dimensional NMR spectroscopy and high-resolution tandem mass spectrometry as the compounds[Asp^(3),(E)-Dhb^(7)]MC-LY(1),[Asp^(3),(E)-Dhb^(7)]MC-HtyW(2),and[Asp^(3),(E)-Dhb^(7)]MC-LW(3).The amino acids found at the variable positions 2 and 4 of the microcystin core structure are in accordance with the predicted amino acid substrate activation selectivities of the non-ribosomal peptide synthetases McyA and McyB described earlier for this strain.All structural microcystin variants produced by this strain were shown to inhibit protein phosphatase 1 in the nanomolar range.
基金Financial support by the federal state of Mecklenburg-Vorpommern and the EU(“Landesforschungsschwerpunkt”EMAU 0201520)is gratefully acknowledged.
文摘Two farnesylhydroquinones were isolated from the fruiting bodies of Ganoderma pfeifferi,farnesylhydroquinone(1)and the new compound ganomycin K(2),(5S)-3-[(E)-7,8-dihydroxy-4,8-dimethylnon-3-enyl]-5-(2,5-dihydroxyphenyl)-furan-2(5H)-one.The structures of 1 and 2 were determined on the basis of mass spectrometric and NMR spectroscopic evidence.The antibacterial activity of the isolated compounds was neglectable.
