Correlations between CNDO/2 charge distribution and 13C NMR chemical shift in 7-acylamino side chains of cephalosporins.
- 1 January 1984
- journal article
- research article
- Published by Japan Antibiotics Research Association in The Journal of Antibiotics
- Vol. 37 (12) , 1642-1650
- https://doi.org/10.7164/antibiotics.37.1642
Abstract
Molecular orbital calculations by the CNDO/2D method yield charge distributions which correlate well with the observed 13C NMR chemical shift for the amide C of acylamino side chains of cephalosporins. Acyl groups that withdraw electrons from the amide C-N bond and concomitantly make the amide N more negatively charged increase the chemical shift. The trends are related to the degree of amide resonance. No direct correlation was found between the chemical shift of the amide C and the antibacterial activity of the cephalosporins.This publication has 7 references indexed in Scilit:
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