13C NMR study of some derivatives of 1,3,4‐oxadiazoles, 1,3,4‐thiadiazoles and isosydnones
- 1 March 1982
- journal article
- research article
- Published by Wiley in Magnetic Resonance in Chemistry
- Vol. 18 (3) , 159-164
- https://doi.org/10.1002/mrc.1270180310
Abstract
The assignment of all ring carbons of 37 derivatives of 1,3,4‐oxa‐ or thiadiazoles and of seven isosydnones is described. In some cases, 13C‐labelled compounds were used. The analysis of substituent effects and the calculation of charge densities of some of the derivatives suggest that the two nitrogen atoms form a protective screen against electron perturbation and play the role of an ‘electronic buffer’. A notable variation of chemical shifts could be observed only when oxygen is replaced by sulphur.Keywords
This publication has 17 references indexed in Scilit:
- Fragmentation mechanism for the loss of XCY (X and Y = O, OR, S) from 2-phenyl-1,3,4-oxadiazole-5-one and related sulfur-containing compoundsJournal of Mass Spectrometry, 1981
- Carbon-13 nuclear magnetic resonance studies of allylic hydroxysterols. Assignment of structure of 5.alpha.-cholest-8(14)-ene-3.beta.,7.alpha.,15.alpha.-triol, an inhibitor of sterol synthesisThe Journal of Organic Chemistry, 1979
- NMR spectral studies: XIII—titanium tetrachloride-induced and lanthanide-induced shifts in the proton NMR spectra of β-lactamsMagnetic Resonance in Chemistry, 1976
- Carbon-13 magnetic resonance. XXVI. Quantitative determination of the tautomeric populations of certain purinesJournal of the American Chemical Society, 1975
- Analyse des Effets de Substituant du Noyau Benzenique EN RMN du Fluor: Application aux Fluoro-2 Alcools PhenylethyliquesMagnetic Resonance in Chemistry, 1972
- Five-membered Heterocyclic Thiones. Part I. 1,3,4-Oxadiazole-2-thioneCanadian Journal of Chemistry, 1972
- Substituted methyl groupsTetrahedron, 1971
- Nuclear magnetic resonance studies. XVI. Oxygen-17 shieldings of some substituted acetophenonesCanadian Journal of Chemistry, 1969
- Molecular Orbital Calculations of the Electronic Structure of the SydnonesJournal of Pharmaceutical Sciences, 1966
- Tautomeric Cyclic Thiones. Part II. Tautomerism, Acidity and Electronic Spectra of Thioamides of the Oxadiazole, Thiadiazole, and Thiazole Groups.Acta Chemica Scandinavica, 1966