Experimental and theoretical investigation of 5-para-fluoro-benziliden-tiazolidin-2tion-4-ona

The 5-para-fluoro-benziliden-tiazolidin-2-tion-4-ona molecule was recently synthesized in the Department of Pharmaceutical Chemistry, UMF "luliu Hatieganu" Cluj-Napoca, and it was shown to be a very efficient antibiotic that has a superior activity to ampicilin on beta-hemolvtic Streptococcus. The molecular vibrations of 5pFBTT were investigated in polycrystalline sample, at room temperature, by Fourier Transform Infrared Spectroscopy (FT-IR), IR-ATR and FT-Raman spectroscopy. In parallel, quantum chemical calculations based on Density Functional Theory (DFT) are used to determine the geometrical, energetic and vibrational characteristics of the molecule. All the possible conformers and tautomers have been considered and analyzed by theoretical methods. All the experimental vibrational bands of 5pFBTT were assigned to normal modes on the basis of DFT calculations at the B3LYP and BLYP levels of theory in conjunction with the standard 6-31 G(d) basis set. Using a uniform scaling of calculated frequencies, a very good correlation was obtained between the experimental and theoretical vibrational data.