Theoretical and experimental H-1, C-13, N-15, and O-17 NMR spectra of 5-nitro, 5-amino, and 5-carboxy uracils

Theoretical and experimental H-1, C-13, N-15, and O-17 NMR Spectral paramet ers of uracil and 5-nitro, 5-amino and 5-carboxy uracils were determined an d analyzed. The theoretical spectra were calculated by the CHF-GIAO method using the polarized double zeta Hansen-Bouman basis set and the polarized t riple zeta Sadlej basis set. For all the nuclei studied, the effect of subs tituents on the chemical shifts of H-1, C-13, N-15, and O-17 nuclei of 5-su bstituted uracils was analyzed. All the carbon-proton and one-bond carbon-c arbon spin-spin coupling constants were also measured. (C) 1999 Elsevier Sc ience B.V. All rights reserved.