Conformational analysis of ochratoxin a by NMR spectroscopy and computational molecular modeling.
Two-dimensional NMR spectroscopy has been used for a complete assignment of the proton and carbon-13 spectra of the metabolite from Aspergillus ochraceus, ochratoxin A. In addition, phase-sensitive nuclear Overhauser effect spectrometry experiments and computational molecular modeling (MM2 and MMFF force field programs) have been employed to examine the conformational properties of ochratoxin A in chloroform solutions. Particular attention has been given to intramolecular hydrogen-bonding formation involving the phenolic group on dihydroisocoumarin, which may be responsible for the toxic mechanism of ochratoxin A.
Dais
Photis
P
NMR Laboratory, Department of Chemistry, University of Crete, 71409 Iraklion, Crete, Greece. dais@chemistry.uoc.gr
Stefanaki
Irine
I
Fragaki
Georgia
G
Mikros
Emannuel
E
D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008958:Models, Molecular; D008968:Molecular Conformation; D009793:Ochratoxins / Q000737:chemistry*
D009793:Ochratoxins; C025589:ochratoxin A