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Abstract
To develop the newer pharmaceuticals and to spur the strong growth, being a general property of 'handedness', chirality plays a major role. The Easson-Stedman principle shows the differences in the biological activity between enantiomers resulted from selective reactivity of one enantiomer with its receptor. It helps to improve the pharmacokinetic properties and to remove undesirable side effects by virtue of the unique activity of enantiomers. Racemic switching and marketing drug combinations are used as tools for drug life-cycle management and to redevelop racemic mixtures as single enantiomers.
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Shah AK, Agrawal YK, Banerjee SK. Spectrophotometric Determination of Thiacetazone. ANAL LETT 2007. [DOI: 10.1080/00032718108081412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Agrawal YK, Patel MP, Merh SS. Lead in soils and plants: its relationship to traffic volume and proximity to highway (Lalbag, Baroda city). ACTA ACUST UNITED AC 2007. [DOI: 10.1080/00207238108709873] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Jain VK, Pandya RA, Pillai SG, Agrawal YK, Kanaiya PH. Solid-phase extractive preconcentration and separation of lanthanum(III) and cerium(III) using a polymer-supported chelating calix [4] arene resin. JOURNAL OF ANALYTICAL CHEMISTRY 2007. [DOI: 10.1134/s1061934807020025] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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Agrawal YK, Vaidya H, Bhatt H, Manna K, Brahmkshatriya P. Recent advances in the treatment of thromboembolic diseases: Venous thromboembolism. Med Res Rev 2007; 27:891-914. [PMID: 17318813 DOI: 10.1002/med.20100] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Venous thromboembolic diseases are the major concern of rising cost of healthcare and are commonest health problem across the globe. Both genetic and acquired risk factors are believed to be strongly linked with these diseases. Commonly encountered problems to the therapy include dose fixing and routine monitoring, yet some serious problems of bleeding also necessitate the immediate need to develop new agents. The review is primarily concerned with the new developments in the treatment of thromboembolic diseases. Therapeutic applications of anticoagulants, antiplatelets, and thrombolytics have been discussed in enough detail.
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Agrawal YK. N-p-tolyl-2-furohydroxamic Acid as the Extracting and Spectrophotometric Reagent for Vanadium(V). ANAL LETT 2006. [DOI: 10.1080/00032717408058801] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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Shukla JP, Agrawal YK, Bhatt K. Rapid Solvent Extraction of Uranium(VI) withN-Phenylbenzohydroxamic Acid. ACTA ACUST UNITED AC 2006. [DOI: 10.1080/00372367308058012] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Rastogi RP, Srivastava RC, Agrawal YK. Dynamic instability at liquid/vapor interface far from equilibrium. J Colloid Interface Sci 2006; 297:711-4. [PMID: 16338233 DOI: 10.1016/j.jcis.2005.10.064] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2005] [Revised: 10/18/2005] [Accepted: 10/29/2005] [Indexed: 10/25/2022]
Abstract
Attempt has been made to elucidate the mechanism of electric potential oscillations at oil-aqueous solution interface involving adsorption at oil-vapor interface on a semi-theoretical basis. The mechanism stipulates adsorption of ammonia, amines and pheromones at the liquid-vapor interface followed by transfer of ions through membrane-aqueous solution interface and subsequent interaction of ammonium (amine) ions and carbocations from pheromones with diffusing halide ions from the bulk. Relationship of the above mechanism with sensing mechanism of smell by olfactory nerves has also been pointed out.
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Agrawal YK, Patadia RN. Microwave‐Assisted Synthesis of Calix[4]resorcinarene Hydroxamic Acids. SYNTHETIC COMMUN 2006. [DOI: 10.1080/00397910500498895] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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Jain VK, Pandya RA, Pillai SG, Shrivastav PS, Agrawal YK. Merrifield Resin Supported Chelate Forming Calix[4]arene‐o‐vanillinthiosemicarbazone Resin Employed for the Separation, Preconcentration and Trace Determination of Cr(VI), As(III) and Tl(I) in Water Samples. SEP SCI TECHNOL 2006. [DOI: 10.1080/01496390500445626] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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Agrawal YK, Patel RN. Chiral chromatographic separation of beta-blockers. J Chromatogr B Analyt Technol Biomed Life Sci 2005; 820:23-31. [PMID: 15866489 DOI: 10.1016/j.jchromb.2005.03.003] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2004] [Revised: 02/12/2005] [Accepted: 03/01/2005] [Indexed: 11/20/2022]
Abstract
A novel amide based chiral stationary phase m-[(+)-alpha-methyl benzyl carboxamide] XAD-4 has been synthesized by covalently linking R(+)-1-phenylethylamine to chloroformoyl Amberlite XAD-4 under weak alkaline conditions. The synthesized resin has been primarily characterized by m.p., elemental analysis and FT-IR and 13C NMR spectra. beta-Blockers viz. atenolol, metoprolol, and propranolol were successfully separated into their enantiomers using a mixture of sodium acetate-acetic acid buffer (pH 4.1):acetonitrile (4:6, v/v) solution using the synthesized resin. Hydrogen bonding and pi-pi interactions are supposed to be the major analyte-chiral stationary phase interactions.
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Patel G, Agrawal YK. Separation and trace estimation of benzidine and its macromolecular adducts using supercritical fluid chromatography. J Chromatogr B Analyt Technol Biomed Life Sci 2003; 795:157-65. [PMID: 14522020 DOI: 10.1016/s1570-0232(03)00558-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
A sensitive, rapid, selective and reproducible method has been developed to measure blood plasma levels of benzidine (BZ) and its acetylated metabolite, N-OH-N,N'-diacetylbenzidine (N-OH-DABZ), using supercritical fluid chromatography (SFC) for the first time. Benzidine and N-OH-N,N'-diacetylbenzidine were extracted from the plasma using ether. Separation was done on a Nucleosil (250 mm x 4.6 mm) 10 microm, Nucleosil-RP-C18 column with 7.4% (v/v) methanol-modified supercritical fluid carbon dioxide (2.5 ml min(-1)) as mobile phase. The column temperature was 45 degrees C and the outlet pressure was set at 8.83 MPa. The detection was done using a UV-Vis detector set at 280 nm. The limit of quantification was 0.10 ng ml(-1) (BZ) and 0.14 ng ml(-1) (N-OH-diacetylbenzidine) using 1 ml plasma specimen. The mean extraction recovery of BZ was found to be 98.6%. The SFC method was directly compared to a published HPLC-UV method. With respect to speed, organic solvent usage, sensitivity, specificity and accuracy, SFC was found to be superior. The method has been successfully used to estimate the BZ, N-OH-diacetylbenzidine levels in blood plasma of the animals who were administered 15 microg kg(-1) body weight of benzidine.Further, this method has been also applied for the detection and quantification of benzidine DNA and hemoglobin adducts from the blood and tissue samples of the benzidine dosed animals.
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Girdhar R, Jain VK, Menon SK, Agrawal YK. Spectrophotometric determination of sulphacetamide. BOLLETTINO CHIMICO FARMACEUTICO 2002; 141:311-4. [PMID: 12426820] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/27/2023]
Abstract
A new rapid selective spectrophotometric method for the determination of sulphacetamide is described. The drug forms a orange-yellow colored complex with Cerium(IV) in sulfuric acid media which is extracted into ethyl acetate. The complex exhibits a maximum absorbance at 440 nm with a molar absorptivity of 3 x 10(2) 1 mol-1 cm-1. The system obeys Beer's law in the concentration range of 0.07-1.1 mg of sulphacetamide. The various parameters for the optimum extraction conditions are discussed. The method is applied to the determination of sulphacetamide in dosage forms.
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Raghavan TNV, Agrawal YK. Analysis of Trace Metals in Petroleum Crudes. 1. Trace Analysis of Vanadium and Titanium in Crude Petroleum of North Gujarat. ACTA ACUST UNITED AC 2002. [DOI: 10.1021/i360070a014] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Agrawal YK. Extraction and spectrophotometric determination of vanadium(V) with N-phenyl-2-naphthohydroxamic acid. Anal Chem 2002. [DOI: 10.1021/ac60356a039] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Jagadheesan K, Agrawal YK, Sinha VK, Nizamie SH. Agranulocytosis during clozapine therapy. Indian J Psychiatry 2000; 42:447-9. [PMID: 21407991 PMCID: PMC2962756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/11/2022] Open
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Agrawal YK, Majumdar F. Effect of binders on anti hypertensive drugs. BOLLETTINO CHIMICO FARMACEUTICO 1999; 138:531-43. [PMID: 10765470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/16/2023]
Abstract
Tablets of antihypertensive drugs, Indapamide, Methyldopa and Clonidine have been prepared and their physico-chemical properties were determined. The effect of various binders viz. starch, acacia, sodium carboxymethyl cellulose (sod. CMC), gelatin and lactose on the properties of these tablets were studied. Formulations of tablets of indapamide, methyldopa and clonidine prepared in combination with acacia, lactose and sod. CMC, respectively result in the best flow properties, minimum percentage fines, low angle of repose and compressibility. The tablets prepared from these granules possess all quality features including a good dissolution profile. Gelatin, sod. CMC and starch have less effective granule formation leading to poor quality of tablets in case of Indapamide, Methyldopa and Clonidine, respectively.
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Agrawal YK, Menon SK, Majumudar F, Jain VK. Thermodynamic ionization constants of antihypertensive drugs. BOLLETTINO CHIMICO FARMACEUTICO 1999; 138:253-8. [PMID: 10464974] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/13/2023]
Abstract
The thermodynamic ionization constants (pKa) of indapamide, clonidine and methyldopa have been determined at 25 degrees C and 35 degrees C by pH titration technique. The pKa varies linearly with mole fraction of dioxane. The thermodynamic parameters have been calculated.
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Jain VK, Sait SS, Shrivastav P, Agrawal YK. Sequential Separation and Trace Enrichment of Thorium(IV) and Uranium(VI) on Chelating Resin Amberlite XAD-2-ortho-vanillinthiosemicarbazone (o-VTSC). SEP SCI TECHNOL 1998. [DOI: 10.1080/01496399808545906] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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