NIR-FT Raman, FT-IR and surface-enhanced Raman scattering spectra, with theoretical simulations on chloramphenicol
Fiche publication
Date publication
décembre 2008
Auteurs
Membres identifiés du Cancéropôle Est :
Pr SOCKALINGUM Ganesh
Tous les auteurs :
Sajan D, Sockalingum GD, Manfait M, Joel IH, Jayakumar VS
Lien Pubmed
Résumé
Chloramphenicol (CLM), originally derived from the bacterium Streptonzyces venezuelae, is an inhibitor of bacterial ribosomal peptidyl transferase activity. The near infrared Fourier transform (NIR-FT) Raman, surf ace-enhanced Raman spectroscopy (SERS) and Fourier transform infrared (FT-IR) spectral analyses of CLM, a potential antibacterial drug for the treatment of typhoid fever, were carried out along with density functional computations. The vibrational spectral analysis reveals that the CH2 asymmetric and symmetric stretching modes are shifted to higher wavenumbers than the computed values, owing to the electronic effects resulting from induction of methylene group with the adjacent electronegative atom. The lowering of C=O stretching wavenumber is due to the presence of the strong electronegative atom, nitrogen, attached to the carbonyl carbon, causing large degree of molecular pi-electron delocalization and redistribution of electrons, which weakens the C=O bond. The absence of a C-H stretching vibration and the observed C-H out-of-plane bending modes suggest that the CLM molecule may be adsorbed in a flat orientation with respect to the silver surface. Copyright (C) 2008 John Wiley & Sons, Ltd.
Référence
J Raman Spectrosc. 2008 Dec;39(12):1772-83