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A series of tri- and tetraarylpiperidin-4-one oximes were synthesized from 2e,3e,6e-tri- and 2e,3e,5e,6e-tetraarylpiperidin-4-ones, respectively. In the case of the latter compounds, oximation is accompanied by epimerization at C-5 to avoid the A1,3-strain between the oxime OH group and the 5e-aryl ring of the initially formed oxime resulting in 2e,3e,5a,6e-tetraarylpiperidin-4-one oximes. 1H, 13C and 2D NMR spectroscopic data were employed to characterize and investigate the stereochemistry of these compounds. Copyright © 2004 John Wiley & Sons, Ltd.

Ten 2-aryl-3-(2′,4′-dinitrophenylthio)cyclohexenes were prepared, their 1H NMR spectra measured and chemical shifts assigned on the basis of nuclear Overhauser enhancements, H,H-COSY spectra and other considerations. Analysis of the data suggests the preference of the conformer with (i) the arylthio group in the axial orientation and (ii) the dinitrophenyl group oriented away from the cyclohexene ring. The NOE results and molecular modeling calculations also support the above conclusions. Copyright © 2000 John Wiley & Sons, Ltd.

The reaction of triarylideneacetylacetones with hydrazine hydrate in acetic acid affords an excellent yield of (E)-s-trans-1-acetyl-5-aryl-3-styryl-2-pyrazolines via decinnamoylation. The structures of these compounds were elucidated using 1H, 13C and two-dimensional NMR techniques such as H,H-COSY, C,H-COSY, NOESY and HMBC. 15N NMR data for these compounds were also obtained and the results are discussed. Copyright © 1999 John Wiley & Sons, Ltd.

The H-1 and C-13 NMR spectra of 4,8,9,10-tetraaryl-1,3-diazatricyclo3.3.1.1(3,7)]decan-6-ones were measured at 400 and 500 and at 100 and 125 MHz, respectively. The chemical shifts were assigned unambiguously using one- and two-dimensional (H,H-COSY, C,H-COSY, NOESY, ROESY and HMBC) NMR spectroscopic data. 1D-INADEQUATE data also provide an independent assignment of the signals of the carbons of the heterocyclic rings. These results clearly indicate the axial orientation of two aryl groups in one piperidone ring and the equatorial orientation, of the other two aryl groups in another ring. Copyright (C) 2001 John Wiley & Sons, Ltd.

The 1H and 13C NMR spectra of seven 2-substituted phenyl methyl sulphides were measured and their chemical shifts assigned on the basis of two-dimensional NMR techniques such as H,H-COSY and C,H-COSY. The chemical shifts of these sulphides were correlated with the appropriate SCS values of monosubstituted benzenes. The influence of the variable substituent on the SCS values of the methylthio group at C-4 is explicable on the basis that the increased electronic repulsion and/or steric interaction between the 2-substituent and the methylthio group enhances the resonance interaction of the latter with the aromatic ring. Copyright © 2000 John Wiley & Sons, Ltd.