title: Conformational analysis of ochratoxin a by NMR spectroscopy and computational molecular modeling.
abstract: 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.
authors.affiliation: NMR Laboratory, Department of Chemistry, University of Crete, 71409 Iraklion, Crete, Greece. dais@chemistry.uoc.gr
authors.forename: Photis
authors.initials: P
authors.lastname: Dais
authors.forename: Irine
authors.initials: I
authors.lastname: Stefanaki
authors.forename: Georgia
authors.initials: G
authors.lastname: Fragaki
authors.forename: Emannuel
authors.initials: E
authors.lastname: Mikros
mesh_terms: D009682:Magnetic Resonance Spectroscopy / Q000379:methods*; D008958:Models, Molecular; D008968:Molecular Conformation; D009793:Ochratoxins / Q000737:chemistry*
chemical_list: D009793:Ochratoxins; C025589:ochratoxin A