title: Conformational and configurational analysis of an N,N carbonyl dipyrrinone-derived oximate and nitrone by NMR and quantum chemical calculations.
abstract: The geometries and relative energies of new N,N carbonyl dipyrrinone-derived oxime molecules (E/Z-s-cis 4a and E/Z-s-cis 4b) have been investigated. The calculated energies, molecular geometries, and (1) H/(13) C NMR chemical shifts agree with experimental data, and the results are presented herein. The E-s-cis conformations of 4a and 4b and the Z-s-cis conformation of 5b were found to be the thermodynamically most stable isomers with the oxime hydrogen atom or the methyl functional group adopting an anti-orientation with respect to the dipyrrinone group. This conformation was unambiguously supported by a number of 2D NMR experiments.
authors.affiliation: Department of Chemistry, University of West Florida, Pensacola, FL, USA.
authors.forename: Ian
authors.initials: I
authors.lastname: Walton
authors.forename: Marauo
authors.initials: M
authors.lastname: Davis
authors.forename: Liu
authors.initials: L
authors.lastname: Yang
authors.forename: Yong
authors.initials: Y
authors.lastname: Zhang
authors.forename: Destin
authors.initials: D
authors.lastname: Tillman
authors.forename: William L
authors.initials: WL
authors.lastname: Jarrett
authors.forename: Michael T
authors.initials: MT
authors.lastname: Huggins
authors.forename: Karl J
authors.initials: KJ
authors.lastname: Wallace
mesh_terms: D000931:Antidotes / Q000032:analysis* / Q000138:chemical synthesis; D015374:Biosensing Techniques / Q000379:methods; D002801:Cholinesterase Reactivators / Q000032:analysis* / Q000138:chemical synthesis; D009682:Magnetic Resonance Spectroscopy; D008968:Molecular Conformation; D009589:Nitrogen Oxides / Q000032:analysis* / Q000737:chemistry; D010091:Oximes / Q000032:analysis* / Q000737:chemistry; D011726:Pyridinium Compounds / Q000032:analysis* / Q000138:chemical synthesis; D011789:Quantum Theory; D013237:Stereoisomerism; D013816:Thermodynamics
chemical_list: D000931:Antidotes; D002801:Cholinesterase Reactivators; D009589:Nitrogen Oxides; D010091:Oximes; D011726:Pyridinium Compounds; C015388:nitrones