1
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Evidence of low temperature phase transition in 2,6-dimethylpyrazine - picric acid cocrystal by means of temperature dependent investigations: X-ray, DSC and IR. J Mol Struct 2021. [DOI: 10.1016/j.molstruc.2020.129432] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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2
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Conformational analysis and quantum descriptors of two bifonazole derivatives of immense anti-tuber potential by using vibrational spectroscopy and molecular docking studies. Struct Chem 2020. [DOI: 10.1007/s11224-020-01678-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
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3
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Synthesis, spectroscopic, thermal, structural investigations and biological activity studies of charge-transfer complexes of atorvastatin calcium with dihydroxy-p-benzoquinone, quinalizarin and picric acid. J Mol Struct 2020. [DOI: 10.1016/j.molstruc.2020.128564] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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4
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Karmakar A, Singh B. Investigation of charge-transfer hydrogen bonding interaction of 1-(2-pyridylazo)-2-naphthol (PAN) and 4-(2-Pyridylazo)resorcinol (PAR) with chloranilic acid through experimental and DFT studies. J Mol Struct 2018. [DOI: 10.1016/j.molstruc.2018.03.069] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/16/2023]
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5
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Miyan L, Zulkarnain, Ahmad A. Spectroscopic and spectrophotometric studies on hydrogen bonded charge transfer complex of 2-amino-4-methylthiazole with chloranilic acid at different temperatures. J Mol Liq 2018. [DOI: 10.1016/j.molliq.2018.04.084] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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6
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Validated spectrophotometric methods for the determination of bifonazole in pharmaceuticals by charge transfer complexation. ACTA ACUST UNITED AC 2018. [DOI: 10.1016/j.jaubas.2014.07.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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7
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Dhamodharan P, Sathya K, Dhandapani M. Spectral, thermal, structural and quantum chemical calculations of 3,5-dimethyl-1H-pyrazol-2-ium-3-hydroxy-2,4,6-trinitrophenolate - A new organic proton transfer crystal. J Mol Struct 2017. [DOI: 10.1016/j.molstruc.2017.08.025] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
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8
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Zulkarnain, Miyan L, Ahmad A, Fazle Alam M, Younus H. Synthesis, single-crystal, DNA interaction, spectrophotometric and spectroscopic characterization of the hydrogen-bonded charge transfer complex of 2-aminopyrimidine with π-acceptor chloranilic acid at different temperature in acetonitrile. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2017; 174:195-208. [DOI: 10.1016/j.jphotobiol.2017.07.002] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/09/2017] [Revised: 06/23/2017] [Accepted: 07/03/2017] [Indexed: 01/01/2023]
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9
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Refat MS, Adam AMA, El-Sayed MY. Biomarkers charge-transfer complexes of melamine with quinol and picric acid: Synthesis, spectroscopic, thermal, kinetic and biological studies. ARAB J CHEM 2017. [DOI: 10.1016/j.arabjc.2014.02.012] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
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10
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Singh N, Khan IM, Ahmad A, Javed S. Synthesis, spectrophotometric and thermodynamic studies of charge transfer complex of 5,6-dimethylbenzimidazole with chloranilic acid at various temperatures in acetonitrile and methanol solvents. J Mol Liq 2016. [DOI: 10.1016/j.molliq.2016.06.081] [Citation(s) in RCA: 38] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/27/2023]
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11
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Smith G, Lynch DE. Cyclic heterotetrameric and low-dimensional hydrogen-bonded polymeric structures in the morpholinium salts of ring-substituted benzoic acid analogues. ACTA CRYSTALLOGRAPHICA SECTION C-STRUCTURAL CHEMISTRY 2016; 72:105-11. [PMID: 26846493 DOI: 10.1107/s2053229615024821] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Accepted: 12/26/2015] [Indexed: 11/10/2022]
Abstract
The morpholinium (tetrahydro-2H-1,4-oxazin-4-ium) cation has been used as a counter-ion in both inorganic and organic salt formation and particularly in metal complex stabilization. To examine the influence of interactive substituent groups in the aromatic rings of benzoic acids upon secondary structure generation, the anhydrous salts of morpholine with salicylic acid, C4H10NO(+)·C7H5O3(-), (I), 3,5-dinitrosalicylic acid, C4H10NO(+)·C7H3N2O7(-), (II), 3,5-dinitrobenzoic acid, C4H10NO(+)·C7H3N2O6(-), (III), and 4-nitroanthranilic acid, C4H10NO(+)·C7H5N2O4(-), (IV), have been prepared and their hydrogen-bonded crystal structures are described. In the crystal structures of (I), (III) and (IV), the cations and anions are linked by moderately strong N-H...Ocarboxyl hydrogen bonds, but the secondary structure propagation differs among the three, viz. one-dimensional chains extending along [010] in (I), a discrete cyclic heterotetramer in (III), and in (IV), a heterotetramer with amine N-H...O hydrogen-bond extensions along b, giving a two-layered ribbon structure. With the heterotetramers in both (III) and (IV), the ion pairs are linked though inversion-related N-H...Ocarboxylate hydrogen bonds, giving cyclic R4(4)(12) motifs. With (II), in which the anion is a phenolate rather than a carboxylate, the stronger assocation is through a symmetric lateral three-centre cyclic R1(2)(6) N-H...(O,O') hydrogen-bonding linkage involving the phenolate and nitro O-atom acceptors of the anion, with extension through a weaker O-H...Ocarboxyl hydrogen bond. This results in a one-dimensional chain structure extending along [100]. In the structures of two of the salts [i.e. (II) and (IV)], there are also π-π ring interactions, with ring-centroid separations of 3.5516 (9) and 3.7700 (9) Å in (II), and 3.7340 (9) Å in (IV).
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Affiliation(s)
- Graham Smith
- Science and Engineering Faculty, Queensland University of Technology, GPO Box 2434, Brisbane, Queensland 4001, Australia
| | - Daniel E Lynch
- Exilica Ltd, The Technocentre, Puma Way, Coventry CV1 2TT, England
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12
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Pregabalin and tranexamic Acid evaluation by two simple and sensitive spectrophotometric methods. Int J Anal Chem 2015; 2015:241412. [PMID: 25873964 PMCID: PMC4383309 DOI: 10.1155/2015/241412] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2014] [Accepted: 12/06/2014] [Indexed: 01/08/2023] Open
Abstract
This paper demonstrates colorimetric visible spectrophotometric quantification methods for amino acid, namely, tranexamic acid and pregabalin. Both drugs contain the amino group, and when they are reacted with 2,4-dinitrophenol and 2,4,6-trinitrophenol, they give rise to yellow colored complexes showing absorption maximum at 418 nm and 425 nm, respectively, based on the Lewis acid base reaction. Detailed optimization process and stoichiometric studies were conducted along with investigation of thermodynamic features, that is, association constant and standard free energy changes. The method was linear over the concentration range of 0.02–200 µgmL−1 with correlation coefficient of more than 0.9990 in all of the cases. Limit of detection was in range from 0.0041 to 0.0094 µgmL−1 and limit of quantification was in the range from 0.0137 to 0.0302 µgmL−1. Excellent recovery in Placebo spiked samples indicated that there is no interference from common excipients. The analytical methods under proposal were successfully applied to determine tranexamic acid and pregabalin in commercial products. t-test and F ratio were evaluated without noticeable difference between the proposed and reference methods.
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El-Habeeb AA, Refat MS. Charge transfer complexes beneficial method for determination of fluoxetine HCl pure drug: Spectroscopic and thermal analyses discussions. RUSS J GEN CHEM+ 2014. [DOI: 10.1134/s1070363214090291] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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14
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Singh N, Ahmad A. Synthesis and spectrophotometric studies of charge transfer complexes of p-nitroaniline with benzoic acid in different polar solvents. J Mol Struct 2014. [DOI: 10.1016/j.molstruc.2014.05.076] [Citation(s) in RCA: 36] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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15
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Elqudaby HM, Mohamed GG, El-Din GMG. Analytical studies on the charge transfer complexes of loperamide hydrochloride and trimebutine drugs. Spectroscopic and thermal characterization of CT complexes. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2014; 129:84-95. [PMID: 24727166 DOI: 10.1016/j.saa.2014.02.110] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2014] [Revised: 02/13/2014] [Accepted: 02/16/2014] [Indexed: 06/03/2023]
Abstract
Charge transfer complexes of loperamide hydrochloride (LOP.HCl) and trimebutine (TB) drugs as electron donor with 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ), tetracyanoethylene (TCNE) and 7,7,8,8-tetracyanoquinodimethane (TCNQ) as π-acceptors in acetonitrile were investigated spectrophotometrically to determine the cited drugs in pure and dosage forms. The reaction gives highly coloured complex species which are measured spectrophotometrically at 460, 415 and 842nm in case of LOP.HCl and at 455, 414 and 842nm in case of TB using DDQ, TCNE and TCNQ reagents, respectively. The optimum experimental conditions have been studied carefully and optimized. Beer's law was obeyed over the concentration ranges of 47.70-381.6, 21.50-150.5 and 10.00-100.0μgmL(-1) for LOP.HCl and 37.85-264.9, 38.75-310.0 and 7.75-155.0μgmL(-1) for TB using DDQ, TCNE and TCNQ reagents, respectively. Sandell sensitivity, standard deviation, relative standard deviation, limit of detection and quantification were calculated. The obtained data refer to high accuracy and precision of the proposed method. These results are also confirmed by inter and intra-day precision with percent recovery of 99.18-101.1% and 99.32-101.4% in case of LOP.HCl and 98.00-102.0% and 97.50-101.4% in case of TB using DDQ, TCNE and TCNQ reagents for intra- and inter-day, respectively. These data were compared with those obtained using official methods for the determination of the cited drugs. The stability constants of the CT complexes were determined. The final products of the reaction were isolated and characterized using FT-IR, (1)H NMR, elemental analysis and thermogravimetric analysis (TG). The stoichiometry and apparent formation constant of the complexes formed were determined by applying the conventional spectrophotometric molar ratio method.
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Affiliation(s)
- Hoda M Elqudaby
- National Organization for Drug Control and Research (NODCAR), Pyramid Ave., P.O. 29, Cairo, Egypt
| | - Gehad G Mohamed
- Chemistry Department, Faculty of Science, Cairo University, 12613 Giza, Egypt.
| | - Ghada M G El-Din
- National Organization for Drug Control and Research (NODCAR), Pyramid Ave., P.O. 29, Cairo, Egypt
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16
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Chan EJ, Grabowsky S, Harrowfield JM, Shi MW, Skelton BW, Sobolev AN, White AH. Hirshfeld surface analysis of crystal packing in aza-aromatic picrate salts. CrystEngComm 2014. [DOI: 10.1039/c4ce00095a] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
The structures of picrate salts of extended aza-aromatic bases have been determined and systematically analyzed using the Hirshfeld surface approach.
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Affiliation(s)
- Eric J. Chan
- School of Chemistry and Biochemistry
- M310
- The University of Western Australia
- Crawley, Australia
| | - Simon Grabowsky
- School of Chemistry and Biochemistry
- M310
- The University of Western Australia
- Crawley, Australia
| | - Jack M. Harrowfield
- School of Chemistry and Biochemistry
- M310
- The University of Western Australia
- Crawley, Australia
| | - Ming W. Shi
- School of Chemistry and Biochemistry
- M310
- The University of Western Australia
- Crawley, Australia
| | - Brian W. Skelton
- School of Chemistry and Biochemistry
- M310
- The University of Western Australia
- Crawley, Australia
| | - Alexandre N. Sobolev
- School of Chemistry and Biochemistry
- M310
- The University of Western Australia
- Crawley, Australia
| | - Allan H. White
- School of Chemistry and Biochemistry
- M310
- The University of Western Australia
- Crawley, Australia
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17
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Eldaroti HH, Gadir SA, Refat MS, Adam AMA. Spectroscopic investigations of the charge-transfer interaction between the drug reserpine and different acceptors: towards understanding of drug-receptor mechanism. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 115:309-323. [PMID: 23867639 DOI: 10.1016/j.saa.2013.06.046] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2013] [Revised: 06/06/2013] [Accepted: 06/12/2013] [Indexed: 06/02/2023]
Abstract
The study of the charge-transfer interaction of the drugs may be useful in understanding the drug-receptor interactions and the mechanism of drug action. Structural and thermal stability of charge-transfer (CT) complexes formed between the drug reserpine (Res) as a donor and quinol (QL), picric acid (PA), tetracyanoquinodimethane (TCNQ) or dichlorodicyanobenzoquinone (DDQ) as acceptors were reported. Elemental analysis, electronic absorption, spectrophotometric titration, IR, Raman, (1)H NMR and X-ray powder diffraction (XRD) were used to characterize the new products. The thermal stability of the synthesized CT complexes was investigated using thermogravimetric (TG) analyses, and the morphology and particle size of these complexes were obtained from scanning electron microscopy (SEM). The stoichiometry of the complexes (donor:acceptor molar ratio) was determined to be 1:1 for all complexes. Accordingly the formed CT complexes could be formulated as [(Res)(QL)], [(Res)(PA)], [(Res)(TCNQ)] and [(Res)(DDQ)]. It was found that the obtained CT complexes are nanoscale, semi-crystalline particles, thermally stable and formed through spontaneous reaction. The results obtained herein are satisfactory for estimation of drug Res in the pharmaceutical form.
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Affiliation(s)
- Hala H Eldaroti
- Department of Chemistry, Faculty of Education, Alzaeim Alazhari University, Khartoum, Sudan.
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Eldaroti HH, Gadir SA, Refat MS, Adam AMA. Charge-transfer interaction of drug quinidine with quinol, picric acid and DDQ: Spectroscopic characterization and biological activity studies towards understanding the drug-receptor mechanism. J Pharm Anal 2013; 4:81-95. [PMID: 29403870 PMCID: PMC5761087 DOI: 10.1016/j.jpha.2013.06.003] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2013] [Accepted: 06/24/2013] [Indexed: 11/17/2022] Open
Abstract
Investigation of charge-transfer (CT) complexes of drugs has been recognized as an important phenomenon in understanding of the drug–receptor binding mechanism. Structural, thermal, morphological and biological behavior of CT complexes formed between drug quinidine (Qui) as a donor and quinol (QL), picric acid (PA) or dichlorodicyanobenzoquinone (DDQ) as acceptors were reported. The newly synthesized CT complexes have been spectroscopically characterized via elemental analysis; infrared (IR), Raman, 1H NMR and electronic absorption spectroscopy; powder X-ray diffraction (PXRD); thermogravimetric (TG) analysis and scanning electron microscopy (SEM). It was found that the obtained complexes are nanoscale, semi-crystalline particles, thermally stable and spontaneous. The molecular composition of the obtained complexes was determined using spectrophotometric titration method and was found to be 1:1 ratios (donor:acceptor). Finally, the biological activities of the obtained CT complexes were tested for their antibacterial activities. The results obtained herein are satisfactory for estimation of drug Qui in the pharmaceutical form.
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Affiliation(s)
- Hala H Eldaroti
- Department of Chemistry, Faculty of Education, Alzaeim Alazhari University, Khartoum, Sudan
| | - Suad A Gadir
- Department of Chemistry, Faculty of Education, Alzaeim Alazhari University, Khartoum, Sudan
| | - Moamen S Refat
- Department of Chemistry, Faculty of Science, Taif University, Al-Haweiah, P.O. Box 888, 21974 Taif, Saudi Arabia.,Department of Chemistry, Faculty of Science, Port Said University, Egypt
| | - Abdel Majid A Adam
- Department of Chemistry, Faculty of Science, Taif University, Al-Haweiah, P.O. Box 888, 21974 Taif, Saudi Arabia
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Eldaroti HH, Gadir SA, Refat MS, Adam AMA. Preparation, spectroscopic and thermal characterization of new charge-transfer complexes of ethidium bromide with π-acceptors. In vitro biological activity studies. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 109:259-271. [PMID: 23542517 DOI: 10.1016/j.saa.2013.03.032] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/17/2012] [Revised: 12/12/2012] [Accepted: 03/03/2013] [Indexed: 06/02/2023]
Abstract
Ethidium bromide (EtBr) is a strong DNA binder and has been widely used to probe DNA structure in drug-DNA and protein-DNA interaction. Four new charge-transfer (CT) complexes consisting of EtBr as donor and quinol (QL), picric acid (PA), tetracyanoquinodimethane (TCNQ) or dichlorodicyanobenzoquinone (DDQ) as acceptors, were synthesized and characterized by elemental analysis, electronic absorption, spectrophotometric titration, IR, Raman, (1)H NMR and X-ray powder diffraction (XRD) techniques. The stoichiometry of these complexes was found to be 1:2 ratio and having the formula [(EtBr)(acceptor)]. The thermal stability of the synthesized CT complexes was investigated using thermogravimetric (TG) analyses, and the morphology and particle size of these complexes were obtained from scanning electron microscopy (SEM). The CT complexes were also tested for its antibacterial activity against two Gram-positive bacteria Staphylococcus aureus and Bacillus subtilis and two Gram-negative bacteria; Escherichia coli and Pseudomonas aeuroginosa strains by using Tetracycline as standard and antifungal property against Aspergillus flavus and Candida albicans by using amphotericin B as standard. The results were compared with the standard drugs and significant conclusions were obtained. The results indicated that the [(EtBr)(QL)2] complex had exerted excellent inhibitory activity against the growth of the tested bacterial strains.
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Affiliation(s)
- Hala H Eldaroti
- Department of Chemistry, Faculty of Education, Alzaeim Alazhari University, Khartoum, Sudan.
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20
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Spectral and solvation effect studies on charge transfer complex of 2, 6-diaminopyridine with chloranilic acid. J Mol Liq 2013. [DOI: 10.1016/j.molliq.2013.02.007] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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21
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Adam AMA, Refat MS, Saad HA. Utilization of charge-transfer complexation for the detection of carcinogenic substances in foods: Spectroscopic characterization of ethyl carbamate with some traditional π-acceptors. J Mol Struct 2013. [DOI: 10.1016/j.molstruc.2013.01.033] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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22
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Adam AMA. Structural, thermal, morphological and biological studies of proton-transfer complexes formed from 4-aminoantipyrine with quinol and picric acid. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2013; 104:1-13. [PMID: 23274251 DOI: 10.1016/j.saa.2012.11.042] [Citation(s) in RCA: 38] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2012] [Revised: 11/12/2012] [Accepted: 11/15/2012] [Indexed: 06/01/2023]
Abstract
4-Aminoantipyrine (4AAP) is widely used in the pharmaceutical industry, biochemical experiments and environmental monitoring. However, residual amounts of 4AAP in the environment may pose a threat to human health. To provide basic data that can be used to extract or eliminate 4AAP from the environment, the proton-transfer complexes of 4AAP with quinol (QL) and picric acid (PA) were synthesized and spectroscopically investigated. The interactions afforded two new proton-transfer salts named 1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-aminium-4-hydroxyphenolate and 1,5-dimethyl-3-oxo-2-phenyl-2,3-dihydro-1H-pyrazol-4-aminium-2,4,6-trinitrophenolate for QL and PA, respectively, via a 1:1 stoichiometry. Elemental analysis (CHN), electronic absorption, spectrophotometric titration, IR, Raman, (1)H NMR and X-ray diffraction were used to characterize the new products. The thermal stability of the synthesized CT complexes was investigated using thermogravimetric (TG) analyses, and the morphology and particle size of these complexes were obtained from scanning electron microscopy (SEM). It was found that PA and 4AAP immediately formed a yellow precipitate with a remarkable sponge-like morphology and good thermal stability up to 180°C. Finally, the biological activities of the newly synthesized CT complexes were tested for their antibacterial and antifungal activities. The results indicated that the [(4AAP)(QL)] complex exhibited strong antimicrobial activities against various bacterial and fungal strains compared with standard drugs.
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Affiliation(s)
- Abdel Majid A Adam
- Department of Chemistry, Faculty of Science, Taif University, Al-Haweiah, PO Box 888, Zip Code 21974, Taif, Saudi Arabia.
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El-Habeeb AA, Al-Saif FA, Refat MS. Charge transfer complex of some nervous and brain drugs – Part 1: Synthesis, spectroscopic, analytical and biological studies on the reaction between haloperidol antipsychotic drugs with π-acceptors. J Mol Struct 2013. [DOI: 10.1016/j.molstruc.2012.08.045] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Synthesis, spectroscopic, thermal and antimicrobial investigations of charge-transfer complexes formed from the drug procaine hydrochloride with quinol, picric acid and TCNQ. J Mol Struct 2012. [DOI: 10.1016/j.molstruc.2012.07.017] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Moreno-Fuquen R, Mosquera F, Ellena J, Tenorio JC. 2,4,6-Trinitro-phenyl 3-methyl-benzoate. Acta Crystallogr Sect E Struct Rep Online 2012; 68:o2187. [PMID: 22798853 PMCID: PMC3393988 DOI: 10.1107/s1600536812027407] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/12/2012] [Accepted: 06/16/2012] [Indexed: 11/17/2022]
Abstract
In the title benzoate derivative, C14H9N3O8, the benzene rings form a dihedral angle of 87.48 (5)°. The central ester unit forms an angle of 19.42 (7)° with the methylbenzene ring, indicating a significant twist. In the crystal, the molecules are linked by weak C—H⋯O interactions forming a helical chain along [010].
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Bator G, Sawka-Dobrowolska W, Sobczyk L, Owczarek M, Pawlukojć A, Grech E, Nowicka-Scheibe J. Hydrogen bonded NHO chains formed by chloranilic acid (CLA) with 4,4′-di-t-butyl-2,2′-bipyridyl (dtBBP) in the solid state. Chem Phys 2012. [DOI: 10.1016/j.chemphys.2011.10.033] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/15/2022]
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27
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Charisiadis P, Primikyri A, Exarchou V, Tzakos A, Gerothanassis IP. Unprecedented ultra-high-resolution hydroxy group (1)H NMR spectroscopic analysis of plant extracts. JOURNAL OF NATURAL PRODUCTS 2011; 74:2462-2466. [PMID: 22014168 DOI: 10.1021/np200329a] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
A general method is demonstrated for obtaining ultra-high resolution in the phenolic hydroxy group 1H NMR spectroscopic region, in DMSO-d6 solution, with the addition of picric acid. Line-width reduction by a factor of over 100 was observed, which resulted in line-widths ranging from 1.6 to 0.6 Hz. This unprecedented resolution, in combination with the shielding sensitivity of the hydroxy group absorptions to substituent effects at least up to 11 bonds distant and the application of 2D 1H-13C HMBC techniques, allows the unequivocal structure analysis of natural products with phenolic hydroxy groups in complex plant extracts.
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Affiliation(s)
- Pantelis Charisiadis
- Section of Organic Chemistry and Biochemistry, Department of Chemistry, University of Ioannina, Ioannina, GR-45110, Greece
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Refat MS, Saad HA, Adam AMA. Intermolecular hydrogen bond complexes by in situ charge transfer complexation of o-tolidine with picric and chloranilic acids. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2011; 79:672-679. [PMID: 21531618 DOI: 10.1016/j.saa.2011.03.058] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/27/2011] [Revised: 03/28/2011] [Accepted: 03/31/2011] [Indexed: 05/30/2023]
Abstract
A two new charge transfer complexes formed from the interactions between o-tolidine (o-TOL) and picric (PA) or chloranilic (CA) acids, with the compositions, [(o-TOL)(PA)(2)] and [(o-TOL)(CA)(2)] have been prepared. The (13)C NMR, (1)H NMR, (1)H-Cosy, and IR show that the charge-transfer chelation occurs via the formation of chain structures O-H⋯N intermolecular hydrogen bond between 2NH(2) groups of o-TOL molecule and OH group in each PA or CA units. Photometric titration measurements concerning the two reactions in methanol were performed and the measurements show that the donor-acceptor molar ratio was found to be 1:2 using the modified Benesi-Hildebrand equation. The spectroscopic data were discussed in terms of formation constant, molar extinction coefficient, oscillator strength, dipole moment, standard free energy, and ionization potential. Thermal behavior of both charge transfer complexes showed that the complexes were more stable than their parents. The thermodynamic parameters were estimated from the differential thermogravimetric curves. The results indicated that the formation of molecular charge transfer complexes is spontaneous and endothermic.
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Affiliation(s)
- Moamen S Refat
- Department of Chemistry, Faculty of Science, Port Said, Port Said University, Egypt.
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Sensitive and selective spectrophotometric determination of gabapentin in capsules using two nitrophenols as chromogenic agents. Int J Anal Chem 2011; 2011:619310. [PMID: 21760787 PMCID: PMC3132512 DOI: 10.1155/2011/619310] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2011] [Accepted: 04/20/2011] [Indexed: 11/17/2022] Open
Abstract
Two simple and selective spectrophotometric methods have been proposed for the determination of gabapentin (GBP) in pure form and in capsules. Both methods are based on the proton transfer from the Lewis acid such as 2,4,6-trinitrophenol (picric acid; PA) or 2,4-dinitrophenol (2,4-DNP) to the primary amino group of GBP which works as Lewis base and formation of yellow ion-pair complexes. The ion-pair complexes formed show absorption maximum at 415 and 420 nm for PA and 2,4-DNP, respectively. Under the optimized experimental conditions, Beer's law is obeyed over the concentration ranges of 1.25–15.0 and 2.0–18.0 μg mL−1 GBP for PA and 2,4-DNP methods, respectively. The molar absorptivity, Sandell's sensitivity, detection and, quantification limits for both methods are also reported. The proposed methods were applied successfully to the determination of GBP in pure form and commercial capsules. Statistical comparison of the results was performed using Student's t-test and F-ratio at 95% confidence level, and there was no significant difference between the reference and proposed methods with regard to accuracy and precision. Further, the validity of the proposed methods was confirmed by recovery studies via standard addition technique.
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Khan IM, Ahmad A, Ullah M. Synthesis, crystal structure, antimicrobial activity and DNA-binding of hydrogen-bonded proton-transfer complex of 2,6-diaminopyridine with picric acid. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY B-BIOLOGY 2011; 103:42-9. [DOI: 10.1016/j.jphotobiol.2011.01.010] [Citation(s) in RCA: 82] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/06/2010] [Revised: 12/11/2010] [Accepted: 01/10/2011] [Indexed: 11/28/2022]
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Refat MS, El-Korashy SA, El-Deen IM, El-Sayed SM. Experimental and spectroscopic studies of charge transfer reaction between sulfasalazine antibiotic drug with different types of acceptors. Drug Test Anal 2011; 3:116-131. [DOI: 10.1002/dta.178] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 08/30/2023]
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Refat MS, Didamony HA, El-Nour KMA, Grabchev I, El-Zayat L, Adam AMA. Spectroscopic characterizations on the N,N′-bis-alkyl derivatives of 1,4,6,8-naphthalenediimide charge-transfer complexes. ARAB J CHEM 2011. [DOI: 10.1016/j.arabjc.2010.06.024] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Refat MS. Spectroscopic and thermal investigations of charge-transfer complexes formed between sulfadoxine drug and different types of acceptors. J Mol Struct 2011. [DOI: 10.1016/j.molstruc.2010.11.026] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Khan IM, Ahmad A. Synthesis, spectral and thermal studies of the newly hydrogen bonded charge transfer complex of o-phenylenediamine with pi acceptor picric acid. SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2010; 77:437-441. [PMID: 20594905 DOI: 10.1016/j.saa.2010.06.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2010] [Revised: 05/19/2010] [Accepted: 06/04/2010] [Indexed: 05/29/2023]
Abstract
Newly proton or charge transfer complex [(OPDH)(+)(PA)(-)] was synthesized by the reaction of the donor, o-phenylenediamine (OPD) with acceptor, 2,4,6-trinitrophenol (PAH). The chemical reaction has occurred via strong hydrogen bonding followed by migration of proton from acceptor to donor. UV-vis, (1)H NMR and FTIR spectra, in addition to the thermal and elemental analysis were used to confirm the proposed occurrence of the chemical reaction and to investigate the newly synthesized solid CT complex. The stoichiometry of the CT complex was found to be 1:1. The formation constant and molar extinction coefficient of the CT complex were evaluated by the Benesi-Hildebrand equation.
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Affiliation(s)
- Ishaat M Khan
- Department of Chemistry, Faculty of Science, Aligarh Muslim University, Aligarh, Uttar Pradesh 202002, India.
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Refat MS, El-Korashy SA, El-Deen IM, El-Sayed SM. Charge-transfer complexes of sulfamethoxazole drug with different classes of acceptors. J Mol Struct 2010. [DOI: 10.1016/j.molstruc.2010.07.004] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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