An International Peer Reviewed Research Journal
Frequency : Monthly,
ISSN : 0971 – 3093
Editor-In-Chief (Hon.) :
Dr. V.K. Rastogi
e-mail:[email protected]
[email protected]

AJP ISSN : 0971 – 3093
Vol 28, No 6, June, 2019

Journal of Physics

Vol 28, No 6, June, 2019


Vol. 28 No 6, 2019, 285-298

R Premkumar1, A Milton Franklin Benial1, M A Palafox2, and V K Rastogi5
1PG and Research Department of Physics, N.M.S.S.V.N. College, Madurai-625019, Tamil Nadu, India.
4Departamento de Química-Física I, Facultad de Ciencias Químicas, Universidad Complutense,
Ciudad Universitaria, Madrid-28040, Spain.
5Indian Spectroscopy Society, KC 68/1, Old Kavinagar, Ghaziabad-201 002, India.

In the present study, the quantum chemical and molecular docking investigations on  the biomolecule 5-Iodouracil (5-IU) have been carried out using density functional theory (DFT) calculations. In addition, the inhibitory nature of the molecule was evaluated using molecular docking simulations. The optimization of the molecular geometry was performed by DFT/B3LYP method with DGTZVP basis set using Gaussian 09 program. The molecular reactivity and kinetic stability of the molecule was confirmed through the frontier molecular orbitals analysis. The solvent effects on UV-Visible spectra of the molecule were studied and a blue shift was observed when going from gas phase to solvent phase. The first order hyperpolarizability analysis indicates that the molecule can act as a non-linear optical material. The molecular electrostatic potential surface and Fukui functions analysis reveal the reactive nature of the molecule. The natural bond orbital analysis validates the bioactivity of the molecule. The molecular docking analysis confirms that the title molecule can inhibit the dipeptidyl peptidase-IV (DPP-4) enzyme, which is associated with the type 2 diabetes mellitus (T2DM). Hence, the present investigation paves the way for developing the effective therapies for  the treatment of T2DM. © Anita Publications. All rights reserved.
Keywords: 5-Iodouracil, DFT, FMOs, UV-Visible, MEP, Molecular Docking and Type 2 diabetes mellitus.

Total Refs : 51

Vol. 28, No 6 (2019) 347-386

DFT study of the structure, spectra and some molecular properties of   5-substituted uracil derivatives: A brief review*

Sunila Abraham1, M Alcolea Palafox2, Kaushal Rani3, Ravinder Kumar4, R A Yadav5, S P Singh6, Preeti Mishra3 and V K Rastogi3
1Post Gradúate and Research Department of Physics, Christian College, Chengannur- 689 122, India
2Departamento de Química-Fisica. Facultad de Ciencias Químicas. Universidad Complutense, Madrid- 28040. Spain
3Indian Spectroscopy Society, KC- 68/1, Old Kavinagar, Ghaziabad-201 002, India
4 Department of Physics, Shyam Lal College (Dehli University) Shahadara- 110 032, India
5Department of Physics, Banaras Hindu University, Varanasi-221 005, India
6Department of Physics, Dr B R Ambedkar College, Mainpuri-205 001, India

In this work, optimized molecular structure and the vibrational spectra of uracil and its main 5-monosubstituted derivatives, 5-XU (X = F, Cl, Br, I, CH3, NH2 and NO2 attached to C5 ), were compared. MEP, ESP and HOMO and LUMO energies for these 5-substituted uracil derivatives were computed for the first time. The FTIR spectra were studied with the support of DFT (B3P86, B3LYP, B3PW91, MPW1PW91) calculations using several basis sets. The effects of substitution of X on the carbon atom in position-5 of the uracil ring on the structural parameters, atomic charges and vibrational wavenumbers of uracil were analyzed and substituent-property relationships were established. In addition, several correlations between the structure and spectral parameters were also shown and sites of the nucleophilic and electrophilic attacks were located and compared. Several general conclusions were underlined on these derivatives © Anita Publications. All rights reserved.

Keywords: Uracil, 5-substituted uracils, Geometry, Vibrational spectra, Nucleophilic and Electrophilic attack.

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