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1

Elliptic Fourier analysis on the tympanic bullae in three Meriones species (Rodentia, Mammalia): its application in biosystematics

100%

Momtazi F. , Darvish J. , Ghassemzadeh F. , Moghimi A.

Acta Zoologica Cracoviensia. Ser.A Vertebrata

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2008

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tom 51A

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nr 1-2

2

Differential Pulse Polarographic Study of Mercury Complexes with Some Substituted Pyrimidines in Binary Acetonitrile-Dimethylformamide Mixtures

88%

Maddah B. , Alizadeh K. , Shamsipur M. , Moghimi A. , Ganjali M.

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2006

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tom Vol. 80, nr 5

737-744

EN

The complex formation of Hg2+ ion with five synthesized substituted pyrimidines in binary acetonitrile-dimethylformamide (AN-DMF) mixtures was studied by differential pulse polarography at 25 graduate C. The stoichiometry and stability of the complexeswere determined by monitoring the shift in the Hg2+ differential pulse peak potential against the pyrimidines concentration. In all cases studied, itwas found that the stability of the resulting 1:1 complex decreases drastically by increasing the amount of dimethylformamide in the binary mixtures. The observed stability order in a given solvent mixture is discussed in terms of the solvating ability of the solvent, donor site number, and steric hindrance on the pyrimidines.

3

Novel Proton Transfer Compounds Containing 2,6-Pyridinedicarboxylic Acid and Melamine and Their PbII Complex: Synthesis, Characterization, Crystal Structure and Solution Studies

75%

Sharif M. , Aghabozorg H. , Shokrollahi A. , Kickelbick G. , Moghimi A. , Shamsipur M.

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2006

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tom Vol. 80, nr 6

847-863

EN

Two novel proton transfer compounds LH2, (tataH2)(pydc), and L'H2, (tataH)2(pydc), (pydcH2 = 2,6-pyridinedicarboxylic acid and tata = melamine, 2,4,6-triamino-1,3,5-triazine), were synthesized and characterized by IR, 1Hand 13C NMRspectroscopy and solid state CPMAS 13C NMR. The (tataH2)2[Pb(pydc)2]2x2tata x4H2O complex (1) was prepared using L'H2and lead(II) nitrate, and characterized by IR andNMRspectroscopy and single crystal X-ray analysis. The PbII complex is a binuclear anionic complex [Pb(pydc)2] 2 4 , in which two metal fragments are linked via a central ten-membered PbN(13)C(18)C(22)O(24)Pb(A)N(13A)C(18A)C(22A)O(24A) ring. Extensive hydrogen bonding between carboxylate groups, (tataH2)2+ and water molecules throughout the PbII complex together with ion pairing play important roles in stabilizing the corresponding lattice. The protonation constants of the reactants, the equilibrium constants for the reaction of pydc with tata and the stoichiometry and stability of the PbII complex with L'H2 in aqueous solution were investigated by potentiometric pH titrations. The stoichiometry of one of themost abundant complexed species in solution was found to be the same as that of the crystalline lead complex.

4

Synthesis, X-ray Crystal Structure and Solution Studies of Cu(II) Complexes of a Pyridine Containing Self-Assembling System

75%

Ranjbar M. , Taghavipur M. , Aghabozorg H. , Moghimi A. , Jalali F. , Shamsipur M.

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2002

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tom Vol. 76 / nr 6

785-794

EN

The complexation of a novel pyridine containing self-assembling system LH2, ([pyda_H2] [pydc] (pyda = 2,6-pyridinediamine and pydc_H2 = 2,6-pyridinedicarboxylic acid), with copper(II) acetate leads to the formation of an anionic self-assemble coordination compound, [(pyda_H)]2[Cu(pydc)2]_H2O. The crystal system is monoclinic with a space group P21/n and contains four molecules per unit cell. The unit cell dimensions are: a = 8.2567(19) A, b = 13.097(31) A, c = 23.384(6) A and _ = 94.685(5)_. The four carboxylate groups of two dianions are oriented in a flattened tetrahedral arrangement and the two dianionic units are almost perpendicular to each other. The axial N-Cu-N angle shows 2.65_ deviation from linearity. The complexation reactions in aqueous solution were investigated by potentiometric pH titrations and the equilibrium constants for all major complexes formed are described. The results are presented in the form of distribution diagrams revealing the concentration of individual complex species as a function of pH. The results revealed that, at pH = 4-5, the major complex species in solution is [(pyda_H)]2[Cu(pydc)2].

5

Different Complexation Behavior of a Proton Transfer Compound Obtained from Pyridine-2,6-dicarboxylic Acid and Creatinine with Tl(I), Cu(II), Fe(III) and Bi(III): Synthesis, Characterization, Crystal Structures and Solution Studies

63%

Aghabozorg H. , Ramezanipour F. , Soleimannejad J. , Sharif M. A. , Shokrollahi A. , Shamsipur M. , Moghimi A. , Attar Gharamaleki J. , Lippolis V. , Blake A. J.

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2008

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tom Vol. 82, nr 3

487-507

EN

The different complexation methods of a proton transfer compound, (creatH)(pydcH)źH2O (pydcH2 = pyridine-2,6-di carboxylic acid; creat = creatinine) with metal ions have been studied and formation of [(Tl(pydcH)]n (1), [(Fe(pydc)(H2O)2)2ox]ź6H2O (2), [Cu(pydc)(pydcH2)]ź2H2O (3) and (creatH)2[Bi(pydc)2]2ź4H2O (4) are re ported. The characterization was performed using IR spectroscopy and single crystal X-ray diffraction analysis. The Tl(I) complex [(Tl(pydcH)]n (1) obtained from (creatH)(pydcH)źH2O is a polymeric system, showing only the contribution of the anionic species of (creatH)(pydcH)źH2O to the complexation. The Fe(III) and the Cu(II) complexes [(Fe(pydc)(H2O)2)2ox]ź6H2O (2) (ox = ox a late) and [Cu(pydc)(pydcH2)]ź2H2O (3) were also obtained from (creatH)(pydcH)źH2O. The Bi(III) complex (creatH)2[Bi(pydc)2]2ź4H2O (4) is a dimeric system, showing both contribution of the cationic and anionic fragments. The complexes 1-4 show a variety of structural features including mononuclear, binuclear, polymeric structures and unusual ligand formation. In compounds (1), (2), (3) and (4), a large number of hydrogen bonds are observed. These interactions as well as p-p stacking play an important role in the formation and stabilization of supra molecular systems in the crystal lattices. The stoichiometry and stability of the Cu(II), Tl(I) and Bi(III) complexes with (pydc)(creat) and Fe(III) with pydc-ox mixture in aqueous solution were investigated by potentiometric pH titration.