Experimental and computational study on molecular structure and vibrational analysis of an antihyperglycemic biomolecule: Gliclazide

Theoretical and experimental investigations on vibrational and structural properties of tolazamide

“…As a result, at HF/6-311++G(d,p) level, HOMO-LUMO gap value is more higher, 102.98 kcal/mol, than at B3LYP/6-311++G(d,p) level [14]. The HOMO is located on sulfonylurea group, intensively over pyrrole moiety, the LUMO is more focused on benzene group but there is less concentration on sulfonylurea moiety [14].…”

“…Also, the large first and third-order hyperpolarizabilities are obtained at lower HOMO-LUMO energy gaps [51]. In our previous study [14] HOMO and LUMO energies, and the gap energy value of HOMO-LUMO for gliclazide have been calculated at HF and B3LYP/6-311++G (d,p) level of theory. As a result, at HF/6-311++G(d,p) level, HOMO-LUMO gap value is more higher, 102.98 kcal/mol, than at B3LYP/6-311++G(d,p) level [14].…”

“…In our previous study [14] HOMO and LUMO energies, and the gap energy value of HOMO-LUMO for gliclazide have been calculated at HF and B3LYP/6-311++G (d,p) level of theory. As a result, at HF/6-311++G(d,p) level, HOMO-LUMO gap value is more higher, 102.98 kcal/mol, than at B3LYP/6-311++G(d,p) level [14]. The HOMO is located on sulfonylurea group, intensively over pyrrole moiety, the LUMO is more focused on benzene group but there is less concentration on sulfonylurea moiety [14].…”

“…We have also reported a study on structural and vibrational analysis of similar anti-hyperglycemic biomolecules, gliclazide, previously [14]. Although X-ray diffraction method is one of the most frequently applied techniques for structural characterization of pharmaceutical compounds, but the utility of vibrational spectroscopy method http has gained wide attention, due to its applicability to the shortrange structure of molecular solids; rather than X-ray techniques which are being sensible to the long range order.…”

Energetic stabilities of thiolated pyrimidines on gold nanoparticles investigated by Raman spectroscopy and density functional theory calculations

“…It has been predicted that either the 1H-keto-amino or 2H-enol form will be the most stable [2]. Density functional theory (DFT) calculations have been used to predict the energetic stabilities of self-assembled layers on metal nanoparticle surfaces [3][4][5]. Quantum mechanical calculations may yield the most stable configurations of the adsorbates on metal atom clusters that can be employed to compare the experimental results including those obtained using vibrational spectroscopic tools such as Raman spectroscopy [6,7].…”