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European chemical bulletinVol. 5. No. 8. (2016.)


Classical and Advanced Chemical Sciences

  • Vinita Purohit ,
    Pallavi Mishra :

    Oxidation of several secondary alcohols by morpholinium fluorochromate (MFC) in DMSO leads to the formation of corresponding ketones. The reaction is first order each in MFC and acidity. The reaction exhibited Michaelis-Menten kinetics with respect to alcohols. The oxidation of 2-propanol-d2 (MeCDOHMe) exhibited a substantial primary kinetic isotope effect (kH/kD = 5.16 at 298 K). The oxidation of 2-propanol has been studied in nineteen different organic solvents. The solvent effect has been analysed using Taft's and Swain's multiparametric equations. The reaction was subject to both polar and steric effects of the substituents. A mechanism involving transfer of hydride ion from alcohol to the oxidant, via a chromate ester, has been proposed.

    Keywords: Alcohols, correlation analysis, halochromate, kinetics, mechanism, oxidation

  • Rehab K. Al-Shemary ,
    Ahmed T. Numan ,
    Eman Mutar Atiyah :

    A Schiff base (L, [2,2'-(1E,1'E)-(ethane-1,2-diylbis(azan-1-yl-1-ylidene))bis(methan-1-yl-1-ylidene)dibenzaldehyde]) has been synthesized by reacting o-phathaldehyde with ethylenediamine and characterized with spectral studies and elemental analysis. Mixed ligands complexes of Mn (II), Co (II), Cu (II), Ni (II) and Hg (II) with 1,10-phenanthroline and the Schiff base have been prepared and characterized. The results indicated tetrahedral and square planar structure for the complexes. Biological activity of the ligands and complexes against four selected bacteria viz. Staphylococcus aureus, Bacillus cereus, Escherichia coli and Pseudomonas were also examined. Some of the complexes exhibit good antibacterial activities.

    Keywords: 1,10-phenanthroline, Schiff base, mixed-ligand, transition metal (II) complexes

  • Amit Kumar ,
    K. N. Subbulakshmi ,
    B. Narayana ,
    B. K. Sarojini ,
    László Kótai ,
    Sumati Anthal ,
    Rajni Kant :

    N-{(1Z)-3-Oxo-1-(thiophen-2-yl)-3-[(2E)-2-(thiophen-2-ylmethylidene)hydrazinyl]prop-1-en-2-yl}benzamide:N,N-dimethylformamide (1:1) solvate, (C19H15N3O2S2.C3H7NO), crystallizes in the monoclinic space group C2/c with the following unit cell parameters: a= 21.111(3), b= 8.7685(8), c= 25.742(3) Å, β= 105.273(13)o and Z=8. The crystal structure was solved by direct methods and refined by full matrix least squares procedures to a final R value of 0.0962 for 2155 observed reflections. The crystal structure is stabilized by N–H···O and C–H···O hydrogen bonds. The DMF solvent gives rise to C10-H10···O3 intermolecular interaction.

    Keywords: Hydrazine; Intermolecular hydrogen bond; Crystal structure; Direct methods

  • Adel M. Kamal El-Dean ,
    Shawkat A. Abdel-Mohsen ,
    Yasser A. Elossaily ,
    Istabrak I Hussein :

    5-Amino-3-methyl-1-phenyl-1H-pyrazole-4-carbonitrile (5) was reacted with chloroacetyl chloride under fusion condition to afford two compounds, which identified as 6-chloromethylpyrazolo[3,4-d]pyrimdine (3) and 4-amino-5-chloropyrazolo[3,4-b]pyridine (7) ln different ratios. Treatment of compound (3) with aromatic amines, gave the arylaminomethyl derivatives (8a-c). Compound (3) was reacted with sodium azide, phosphorous oxychloride, sulphanilamide to give new derivatives (9, 10, and 14). The 4-chloro derivative (11) underwent nucleophilic substitution using some reagent such as P2S5, sodium azide and hydrazine hydrate to furnish novel pyrazolo[3,4-d]pyrimidines (12, 13, 15, 16, 17). All synthesized compounds were characterized using elemental analysis and spectral techniques. The antiinflammatory activity of all the newly synthesized compounds was evaluated using the carrageenan induced paw oedema test in rats using indomethacin as the reference drug.

    Keywords: Pyrazolo[3,4-d]pyrimidinone, 6-aryaminomethyl derivatives, sulfa drug, tetrazole, anti-inflammatory activity

  • Yamina Chergui ,
    Adil A. Othman :

    Novel glycosides 2-(1,5-diaminopentyl)-S-fructosyl-1,3,4-oxadiazole-5-thione , 3-(1,5-diaminopentyl)-5-S-glucosyl-1,2,4-triazole-5-thiole and 3-(1,5-diaminopentyl)-4-amino-5-S- or 4-N-glucosyl-1,2,4-triazole-5-thiole are obtained by reacting the appropriate azoles with Dfructose and D-glucose. All intermediates and final products are characterized by IR, 1H-NMR and 13C-NMR. The antimicrobial activities are assessed using the paper disk diffusion and broth dilution methods against Acinetobacter, Pseudomonas aeruginosa, Bacillus cereus, Staphylococcus aureus and Spongospora subterranean. Some of the synthesized compounds showed promising activity against microorganisms under test in comparison with commercially available antibiotics Polymixine and Oxytetracycline.

    Keywords: 1,3,4- oxadiazoles; 1,2,4- triazoles; glycosides ; L-lysine; antimicrobial activities

Chemical and Biological Aspects of Life

  • Hiroshi Ashihara :
    Biosynthesis of 5-phosphoribosyl-1-pyrophosphate in plants: a review314-323en [357.89 kB - PDF]EPA-02286-00044-0060

    5-Phosphoribosyl-1-pyrophosphate (PRPP) is an essential substrate for biosynthesis of nucleotides, tryptophan and histidine, functioning as the phosphoribosyl donor. PRPP is synthesised from ribose-5-phosphate and ATP by PRPP synthetase (ribose phosphate pyrophosphokinase, EC In the present review, the occurrence and biosynthesis of PRPP in plant cells and tissues are summarized, and then the properties of two types of plant PRPP synthetases are described. In addition to the inorganic phosphate (Pi)-dependent PRPP synthetases (class I) which have similar properties to mammalian enzymes, plant specific Pi-independent PRPP synthetases (class II) have been discovered in plants. Finally, reports which show fluctuation of the PRPP synthetase activity accompanied by various physiological phenomena in plants and the transgenic plants which enhanced PRPP synthetase activity and relation to biotechnology are introduced.

    Keywords: 5-phosphoribosyl-1pyrophosphate (PRPP), nucleotide biosynthesis, PRPP synthetase, metabolite, enzyme, plant, PRS gene

  • G. A. Korablev ,
    N. G. Petrova :
    Corpuscular-wave processes in quantum transitions339-344en [746.27 kB - PDF]EPA-02286-00044-0070

    Two principles of adding energy characteristics of structural interactions are fulfilled if the process flows either along the potential gradient or against it. Transforming these rules onto the corpuscular-wave dualism, we can assume that corpuscular interactions flow along the potential gradient (principle of adding reciprocals of energies), and wave processes – against the potential gradient (principle of algebraic addition of energies). Such approach is confirmed by the empiric equation, in which the act of quantum action is narrowed to the energy redistribution in the system “particle-wave”. It is demonstrated that the angular vector of rotational-translation motion of electrons at quantum transitions changes in compliance with the quantum number of the square tangent of this angle.

    Keywords: Potential gradient, quantum transitions, corpuscular-wave dualism, geodesic angle

Theoretical and Computational Chemistry

  • V. I. Krupyanko :

    Symmetric anti-directivity in the course of change in the ratios between KA and KB in the equation v = VAB/(KAKB + KAB +KBA +AB) is suggested to be potential for applying when this equation is used to treat data on the mechanism of enzymatic action involving two (A + B) substrates.

    Keywords: Correction of equation; data analysis of two (A + B) substrate reactions