title: Electronic, Raman and FT-IR spectral investigations of the charge transfer interactions between ketoconazole and povidone drugs with iodine.
abstract: The interaction between ketoconazole and povidone drugs with iodine was found to proceed through initial formation of a charge transfer (CT) complex as an intermediate. The stoichiometry of the complex was found to be 1:1 in the case of povidone-iodine system and 1:2 in the case of ketoconazole-iodine system and the same was confirmed by thermal (TGA/DSC) studies. The formation of I(3)(-) species was confirmed by electronic and laser Raman spectra. The three peaks appeared in Raman spectra, of the isolated adducts corresponds to nu(as)(I-I), nu(s)(I-I) and delta(I(3)(-)), confirmed the presence of asymmetric I(3)(-) ion. The rate of the interaction has been measured as a function of time and solvent. The pseudo-first-order rate constants at various temperatures for the interactions were measured and the activation parameters (DeltaG(#), DeltaS(#) and DeltaH(#)) were computed. Based on the spectral and spectrokinetic evidences a mechanism involving the formation of a polar intermediate and its conversion to the final product has been proposed and discussed.
authors.affiliation: Department of Chemistry, Gandhigram Rural University, Tamil Nadu, India.
authors.forename: M
authors.initials: M
authors.lastname: Pandeeswaran
authors.forename: K P
authors.initials: KP
authors.lastname: Elango
mesh_terms: D000891:Anti-Infective Agents, Local / Q000737:chemistry*; D004563:Electrochemistry; D007455:Iodine / Q000737:chemistry*; D007654:Ketoconazole / Q000737:chemistry*; D015394:Molecular Structure; D011205:Povidone / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry; D017550:Spectroscopy, Fourier Transform Infrared; D013059:Spectrum Analysis, Raman
chemical_list: D000891:Anti-Infective Agents, Local; D012997:Solvents; D007455:Iodine; D011205:Povidone; D007654:Ketoconazole