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A DFT study of vibrational spectra of 5-chlorouracil with molecular structure, HOMO-LUMO, MEPs/ESPs and thermodynamic properties. Polym Bull (Berl) 2023; 80:3055-3083. [PMID: 35378874 PMCID: PMC8968244 DOI: 10.1007/s00289-022-04181-7] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2021] [Revised: 02/12/2022] [Accepted: 03/06/2022] [Indexed: 11/04/2022]
Abstract
The density functional theory calculation has been carried out for the analysis of 5-chlorouracil using DFT/Gaussian 09 with GAR2PED. Recorded experimental spectra for Raman and IR of 5-chlorouracil have been analyzed all fundamental vibrational modes using the outcome results of DFT at 6-311++G** of Gaussian 09 calculations and the GaussView 5.09. To help the analysis of vibrational modes, GAR2PED program has been used in the calculation of PEDs. The charge transfer properties of 5-chlorouracil have been analyzed using HOMO and LUMO level energy analysis. HOMO and LUMO energy gap study supports the charge transfer possibility in molecule. These have been made to study for reactivity and stability of heterocyclic molecules for the analysis of antiviral drugs against the new corona virus: COVID-19. Here, the smaller energy gap of 5-chlorouracil is more responsible for charge transfer interaction in the heterocyclic drug molecules and a reason of more bioactivity. The electron density mapping within molecular electrostatic potential plot and electrostatic potential plotting within iso-surface plot have been evaluated the charge distribution concept in the molecule as the nucleophilic reactions and electrophilic sites. These computations have been used to produce the molecular charges, structure and thermodynamic functions of biomolecule. This study has been made to all internal modes of chloro group substituent at pyrimidine ring of C5 atom. The splitting of frequencies has arisen in the two species for the normal distribution modes. Graphical abstract
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Marinova P, Tsoneva S, Frenkeva M, Blazheva D, Slavchev A, Penchev P. New Cu(II), Pd(II), and Au(III) Complexes with 2-Thiouracil: Synthesis, Characteration, and Antibacterial Studies. RUSS J GEN CHEM+ 2022. [DOI: 10.1134/s1070363222080278] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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3
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Synthesis, structure, NBO, Hirshfeld surface, NMR, HOMO-LUMO, UV, photoluminescence, z scan, vibrational and thermal analysis of piperazinedi-ium tetrakis (μ2‑chloro)-diaqua-dichloro-di-cadmium single crystal. J Mol Struct 2022. [DOI: 10.1016/j.molstruc.2022.132685] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
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4
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Quantum chemical studies of molecular structure, vibrational spectra and nonlinear optical properties of p-iodoaniline and p-bromoaniline. J Mol Struct 2020. [DOI: 10.1016/j.molstruc.2020.128939] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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5
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IR and Raman spectra with Gaussian-09 molecular analysis of some other parameters and vibrational spectra of 5-fluoro-uracil. RESEARCH ON CHEMICAL INTERMEDIATES 2020. [DOI: 10.1007/s11164-020-04101-2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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6
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Singh J. Thermodynamic functions with other properties and vibrational spectra of pyrimidine ring of uracil for RNA and bio-molecule 5-aminouracil. Heliyon 2019; 5:e02955. [PMID: 31872124 PMCID: PMC6909060 DOI: 10.1016/j.heliyon.2019.e02955] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/20/2019] [Revised: 05/19/2019] [Accepted: 11/26/2019] [Indexed: 12/03/2022] Open
Abstract
Vibrational spectra (Infra Red and Raman) of uracil and 5-aminouracil have been recorded as well as reproduced in solid phase for the pyrimidinal region (200-2000 cm−1) and the internal modes were analyzed especially for pyrimidine ring of bio-molecules theoretically by using the density functional theory (DFT) calculations on the different basis sets for Restricted Hartree–Fock (RHF) by employing the Gaussian-03 program. These quantum chemical calculations have been employed to yield the Mulliken atomic charges, atomic polarizability tensor (APT) charges and thermodynamic functional properties of these bio-molecules. These DFT calculations have been computed for the some important internal ring modes especially to pyrimidine ring of uracil with a substituent amino-group (NH2) at site of C5 atom on pyrimidine ring.
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Alswaidan IA, Sooknah K, Rhyman L, Parlak C, Ndinteh DT, Elzagheid MI, Ramasami P. 2,4-Ditellurouracil and its 5-fluoro derivative: Theoretical investigations of structural, energetics and ADME parameters. Comput Biol Chem 2017; 68:56-63. [PMID: 28236747 DOI: 10.1016/j.compbiolchem.2017.02.002] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2016] [Revised: 12/17/2016] [Accepted: 02/02/2017] [Indexed: 11/29/2022]
Abstract
2,4-Ditellurouracil exhibits keto-enol tautomerism via different pathways resulting in seven tautomers. These pathways were studied in the gas phase using density functional theory method. The functionals used were BLYP, B3LYP and BHLYP and the basis sets were 6-311++G(d,p) for all atoms except that LanL2DZ ECP was used for tellurium atom only. The results indicate that the diketo form is more stable as observed for uracil and its sulfur and selenium analogues. The effect of introducing fluorine at position 5 was also investigated and the energy difference between the diketo and dienol forms is reduced. 2,4-Ditellurouracil and its 5-fluoro analogue are expected to exist exclusively as the diketo form due to the high interconversion energy barrier. We extended the investigation to predict ADME parameters of the most stable diketo and dienol tautomers in view of understanding their biological properties. This research enlightens keto-enol tautomerism of 2,4-ditellurouracil and its 5-fluoro derivative with additional insights to biological functions.
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Affiliation(s)
- Ibrahim A Alswaidan
- Department of Pharmaceutical Chemistry, College of Pharmacy, King Saud University, Riyadh 11451, Saudi Arabia
| | - Kritish Sooknah
- Computational Chemistry Group, Department of Chemistry, Faculty of Science, University of Mauritius, Réduit 80837, Mauritius
| | - Lydia Rhyman
- Department of Applied Chemistry, University of Johannesburg, Doornfontein Campus, Johannesburg 2028, South Africa; Department of Chemistry, University of Johannesburg, PO Box 524, Auckland Park, Johannesburg, 2006, South Africa
| | - Cemal Parlak
- Department of Physics, Science Faculty, Ege University, Bornova, Izmir, 35100, Turkey
| | - Derek T Ndinteh
- Department of Applied Chemistry, University of Johannesburg, Doornfontein Campus, Johannesburg 2028, South Africa
| | - Mohamed I Elzagheid
- Department of Chemical and Process Engineering, Jubail Industrial College, Jubail Industrial City 31961, Saudi Arabia
| | - Ponnadurai Ramasami
- Computational Chemistry Group, Department of Chemistry, Faculty of Science, University of Mauritius, Réduit 80837, Mauritius; Department of Applied Chemistry, University of Johannesburg, Doornfontein Campus, Johannesburg 2028, South Africa; Department of Chemistry, University of Johannesburg, PO Box 524, Auckland Park, Johannesburg, 2006, South Africa.
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8
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Dai X, Song D, Liu K, Su H. Photoinduced C—I bond homolysis of 5-iodouracil: A singlet predissociation pathway. J Chem Phys 2017; 146:025103. [DOI: 10.1063/1.4973650] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022] Open
Affiliation(s)
- Xiaojuan Dai
- Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
| | - Di Song
- Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
| | - Kunhui Liu
- Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- College of Chemistry, Beijing Normal University, Beijing 100875, China
| | - Hongmei Su
- Beijing National Laboratory for Molecular Sciences (BNLMS), Institute of Chemistry, Chinese Academy of Sciences, Beijing 100190, China
- University of Chinese Academy of Sciences, Beijing 100049, China
- College of Chemistry, Beijing Normal University, Beijing 100875, China
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9
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Palafox MA, Rastogi V. 6-Aminouracil: Geometries and spectra in the isolated state and in the solid state simulation. A comparison with 5-aminouracil. J Mol Struct 2016. [DOI: 10.1016/j.molstruc.2015.12.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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10
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A DFT analysis of the molecular structure, vibrational spectra and other molecular properties of 5-nitrouracil and comparison with uracil. J Mol Struct 2016. [DOI: 10.1016/j.molstruc.2015.10.096] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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11
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Cuellar A, Alcolea Palafox M, Rastogi VK, Kiefer W, Schlücker S, Rathor SK. FT-IR and FT-Raman spectra of 5-fluoroorotic acid with solid state simulation by DFT methods. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 132:430-445. [PMID: 24887505 DOI: 10.1016/j.saa.2014.04.107] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2014] [Revised: 04/11/2014] [Accepted: 04/22/2014] [Indexed: 06/03/2023]
Abstract
FT-Raman and FT-IR studies of the biomolecule 5-fluoroorotic acid in the solid state were carried out. The unit cell found in the crystal was simulated as a tetramer form by density functional calculations. They were performed to clarify wavenumber assignments of the experimental observed bands in the spectra. Correlations with the molecule of uracil were made, and specific scale equations were employed to scale the wavenumbers of 5-fluoroorotic acid. Good reproduction of the experimental wavenumbers is obtained and the % error is very small in the majority of the bands. This fact confirms our simplified solid state model. The molecular structure was fully optimized using DFT and MP2 methods. The relative stability of both the syn and anti conformations was investigated, and the anti-form was found to be slightly more stable, by 7.49 kJ/mol at the MP2 level. The structures of all possible tautomeric forms were determined. The keto-form appeared as the most stable one. The NBO atomic charges and several thermodynamic parameters were also calculated.
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Affiliation(s)
- A Cuellar
- Departamento de Química-Física I, Facultad de Ciencias Químicas, Universidad Complutense, Madrid 28040, Spain
| | - M Alcolea Palafox
- Departamento de Química-Física I, Facultad de Ciencias Químicas, Universidad Complutense, Madrid 28040, Spain.
| | - V K Rastogi
- R D Foundation Group of Institutions, NH-58, Kadrabad, Modinagar, Ghaziabad, India; Indian Spectroscopy Society, KC 68/1, Old Kavinagar, Ghaziabad 201 002, India.
| | - W Kiefer
- University of Würzburg, Institute for Physical and Theoretical Chemistry, Am Hubland, D-97074 Würzburg, Germany
| | - S Schlücker
- University of Duisburg-Essen, Faculty of Chemistry, Universitätsstr. 5, D-45141 Essen, Germany
| | - S K Rathor
- Indian Spectroscopy Society, KC 68/1, Old Kavinagar, Ghaziabad 201 002, India
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Ortiz S, Alvarez-Ros MC, Palafox MA, Rastogi VK, Balachandran V, Rathor SK. FT-IR and FT-Raman spectra of 6-chlorouracil: molecular structure, tautomerism and solid state simulation. A comparison between 5-chlorouracil and 6-chlorouracil. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 130:653-668. [PMID: 24856263 DOI: 10.1016/j.saa.2014.04.009] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2014] [Revised: 03/27/2014] [Accepted: 04/01/2014] [Indexed: 06/03/2023]
Abstract
A Raman and IR study of the biomolecule 6-chlorouracil was carried out in the solid state. The unit cell found in the crystal was simulated as a tetramer form by density functional calculations. Specific scale factors and scaling equations deduced from uracil molecule were employed in the predicted wavenumbers of 6-chlorouracil. The scaled wavenumbers were used in the reassignment of the IR and Raman experimental bands. Good reproduction of the experimental wavenumbers is obtained and the % error is very small in the majority of cases. A comparison between the molecular structure and charge distribution of 6-chlorouracil and 5-chlorouracil molecules was presented. The effect of the hydration with the PCM model in the molecular structure and charges was discussed. The optimum tautomers of 6-chlorouracil were optimized and analyzed. Six of them were related to those of uracil molecule. The effect of the halogen substitution in the sixth position of the pyrimidine ring in the stability of the different tautomers was evaluated. HOMO and LUMO orbital energy analysis were carried out.
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Affiliation(s)
- S Ortiz
- Departamento de Química-Física-I, Facultad de Ciencias Químicas, UCM, Madrid 28040, Spain
| | - M C Alvarez-Ros
- Departamento de Química-Física-I, Facultad de Ciencias Químicas, UCM, Madrid 28040, Spain
| | - M Alcolea Palafox
- Departamento de Química-Física-I, Facultad de Ciencias Químicas, UCM, Madrid 28040, Spain.
| | - V K Rastogi
- R.D. Foundation Group of Institutions, NH-58, Kadrabad, Modinagar, Ghaziabad, India; Indian Spectroscopy Society, KC-68/1, Old Kavinagar, Ghaziabad 201 002, India.
| | - V Balachandran
- Department of Physics, Arignar Anna Government Arts College, Musiri, Tiruchirappalli 621211, India
| | - S K Rathor
- Indian Spectroscopy Society, KC-68/1, Old Kavinagar, Ghaziabad 201 002, India
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13
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Singh JS. FT-IR and Raman spectra, ab initio and density functional computations of the vibrational spectra, molecular geometries and atomic charges of uracil and 5-halogenated uracils (5-X-uracils; X=F, Cl, Br, I). SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 117:502-518. [PMID: 24036044 DOI: 10.1016/j.saa.2013.08.004] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/11/2013] [Revised: 07/22/2013] [Accepted: 08/02/2013] [Indexed: 06/02/2023]
Abstract
Raman (200-4000 cm(-1)) and FT-IR (400-4000 cm(-1)) spectra of uracil and 5-halogenated uracils (5-X-uracils; X=F, Cl, Br, I) have been recorded and analyzed in the range 200-4000 cm(-1). The optimized molecular geometries, atomic polar tensor (APT) charges and vibrational characteristics have been studied theoretically using restricted Hartree-Fock (RHF) and density functional theory (DFT) methods. Ab initio and DFT calculations [using Becke's exchange in conjunction with Lee-Yang-Parr's correlation functional and Becke's three-parameter hybrid method (B3LYP)] were carried out to study the optimized molecular fundamental vibrational frequencies for uracil and 5-halogenated uracils by employing Gaussian-03 program. Gauss View software was used to make the vibrational analysis. Raman and IR spectra have been computed theoretically for the uracil and 5-halogenated molecules. The fundamental vibrational frequencies along with their corresponding intensities in IR and Raman activities and depolarization ratios of the Raman lines have also been calculated using the RHF and DFT methods employing different basis sets. Quantum chemical calculations helped in the reassignments of some fundamental vibrational modes. Most of the B3LYP/6-311++G(**) vibrational frequencies are in excellent agreement with available experimental assignments. The ring breathing and kekule stretching modes are found to lower magnitudes compared to those for uracil which could be due to mass effect of halogen atom in place of the hydrogen atom. The C-X (X=F, Cl, Br, I) stretching frequency is distinctly separated from the CH/NH ring stretching frequencies on the pyrimidine ring. All other bands have also been assigned different fundamentals/overtones/combinations.
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Affiliation(s)
- J S Singh
- Department of Physics, Anand Engineering College, Keetham, Agra 282007, India.
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14
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Muñoz Freán S, Alcolea Palafox M, Rastogi V. Effect of the microhydration on the tautomerism in the anticarcinogenic drug 5-fluorouracil and relationships with other 5-haloderivatives. J Mol Struct 2013. [DOI: 10.1016/j.molstruc.2013.09.008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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15
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Alcolea Palafox M. Molecular structure differences between the antiviral Nucleoside Analogue 5-iodo-2′-deoxyuridine and the natural nucleoside 2′-deoxythymidine using MP2 and DFT methods: conformational analysis, crystal simulations, DNA pairs and possible behaviour. J Biomol Struct Dyn 2013; 32:831-51. [DOI: 10.1080/07391102.2013.789402] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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16
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Ortiz S, Alcolea Palafox M, Rastogi VK, Akitsu T, Hubert Joe I, Kumar S. Simulation of a tetramer form of 5-chlorouracil: the vibrational spectra and molecular structure in the isolated and in the solid state by using DFT calculations. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 110:404-418. [PMID: 23583877 DOI: 10.1016/j.saa.2013.03.018] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/21/2012] [Revised: 02/19/2013] [Accepted: 03/03/2013] [Indexed: 06/02/2023]
Abstract
A Raman and FT-IR study of the biomolecule 5-chlorouracil in the solid state was carried out. The unit cell found in the crystal was simulated as a tetramer form by density functional calculations. They were performed to clarify the assignments of the experimentally observed bands in the spectra. Calculations in the monomer form and comparisons with the experimental data in Ar matrix were also carried out. The error in the calculated frequencies was analyzed and reduced by using scaling equations and scaling factors deduced from the uracil molecule. The calculations with the B3LYP method and with the 6-31G(d,p) and 6-311+G(2d,p) basis set, appear in general to be useful, when combining with a scaling equation procedure or with the specific scale factors, for interpretation of the general features of the IR and Raman spectra. The scaled values were used in the reassignment of the IR and Raman experimental bands. Comparison of the results with those determined in uracil and 5-halogenated derivatives were performed. The substitution at 5-position of the uracil ring by a chlorine atom has a little effect on the geometric parameters.
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Affiliation(s)
- S Ortiz
- Departamento de Química-Física I, Facultad de Ciencias Quimicas, Universidad Complutense, Madrid 28040, Spain
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Arjunan V, Santhanam R, Subramanian S, Mohan S. Primidone--an antiepileptic drug--characterisation by quantum chemical and spectroscopic (FTIR, FT-Raman, 1H, 13C NMR and UV-Visible) investigations. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 109:282-297. [PMID: 23542519 DOI: 10.1016/j.saa.2013.03.025] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2012] [Revised: 02/20/2013] [Accepted: 03/03/2013] [Indexed: 06/02/2023]
Abstract
The solid phase FTIR and FT-Raman spectra of primidone were recorded in the regions 4000-400 cm(-1) and 4000-100 cm(-1), respectively. The vibrational spectra were analysed and the observed fundamentals were assigned and analysed. The experimental wavenumbers were compared with the theoretical scaled vibrational wavenumbers determined by DFT methods. The Raman intensities were also determined with B3LYP/6-31G(d,p) method. The total electron density and molecular electrostatic potential surface of the molecule were constructed by using B3LYP/6-311++G(d,p) method to display electrostatic potential (electron+nuclei) distribution. The HOMO and LUMO energies were measured. Natural bond orbital analysis of primidone has been performed to indicate the presence of intramolecular charge transfer. The (1)H and (13)C NMR spectra were recorded and the chemical shifts of the molecule were calculated.
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Affiliation(s)
- V Arjunan
- Department of Chemistry, Kanchi Mamunivar Centre for Post-Graduate Studies, Puducherry 605 008, India.
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Anticancer drug IUdR and other 5-halogen derivatives of 2′-deoxyuridine: conformers, hydrates, and structure–activity relationships. Struct Chem 2013. [DOI: 10.1007/s11224-013-0225-1] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Rastogi VK, Palafox MA. Vibrational spectra, tautomerism and thermodynamics of anticarcinogenic drug: 5-fluorouracil. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2011; 79:970-977. [PMID: 21664177 DOI: 10.1016/j.saa.2011.04.008] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2010] [Revised: 03/08/2011] [Accepted: 04/07/2011] [Indexed: 05/30/2023]
Abstract
The FT-IR and FT-Raman spectra of 5-Fluorouracil were recorded in the solid phase in the regions 400-4000 cm(-1) and 50-4000 cm(-1), respectively. The vibrational spectra were analysed and the observed fundamentals were assigned to different normal modes of vibration. The experimental wavenumbers were compared with the scaled vibrational values using DFT methods: the Ar matrix data were related to gas phase calculations, while the values of the solid state spectra were compared to those with dimer simulations. The study indicates that some features that are characteristic of vibrational spectra of uracil and its derivatives are retained in the spectrum of 5-fluorouracil and it exists in ketonic form in the solid phase. The tautomerism was also studied and the spectra of the two most stable forms were simulated. The calculated wavenumbers have been employed to yield thermodynamic properties.
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Affiliation(s)
- V K Rastogi
- Department of Physics, CCS University, Meerut 250 004, India.
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