Chemistry Journal of Moldova

DOI: dx.doi.org/10.19261/cjm.2006.01(1).01

Graphical Abstract: The results of investigation of oenotannins content in the seeds of different grape varieties are presented in the paper. It was demonstrated that the oenotannins content depends on the grape variety as well as on the geographycal zone of grape cultivation. A new procedure for

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DOI: dx.doi.org/10.19261/cjm.2006.01(1).02

Graphical Abstract: Three steroidal glycosides of spirostane series have been isolated from the seeds of Hyoscyamus niger L.(Solanaceae). Their structures were determined on the basis of chemical evidence and extensive spectroscopic methods including one-dimensional, two-dimensional NMR and MS analysis. In the genus Hyoscyamus the given compounds have been found out for the first time.


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DOI: dx.doi.org/10.19261/cjm.2006.01(1).03

Graphical Abstract: The magnetic susceptibility (χT) of an unusual dissymmetric binuclear manganese corboxylate complex has been measured from 2 to 300K. The magnetic data which have been fitted with help of the Heisenberg Dirac Van Vleck HDVV spin-exchange Hamiltonian H = − J S 1 S 2 , indicate that an antiferromagnetic interaction equal to J = -0.90(1) cm-1 is present. A correlation between J values and Mn-H2O-Mn angles has been tempted.


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DOI: dx.doi.org/10.19261/cjm.2006.01(1).04

Graphical Abstract: Reaction in methanol solution of the trinuclear ‘basic’ chromium(III) acetate with Pr(NO₃)₃⋅5H₂O and further extraction by chloroform-acetone mixture led to the formation of novel unusual [Cr₃O(CH₃COO)₆(H₂O)₃]NO₃⋅HNO₃⋅H₂O (1) cluster with one “free” molecule of nitric acid. Complex 1 crystallizes in the monoclinic space group P21/c with, at room temperature, a = 13.624(2), b = 15.032(2), c = 15.180(2) Å, β = 112.98(3) °, Z = 4, and V = 2862.09 Å3. The obtained crystalline compound has been synthesized and characterized by IR and UV/Vis methods.


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DOI: dx.doi.org/10.19261/cjm.2006.01(1).05

Graphical Abstract: Heterometallic complexes of chromium (III) with some 3d metals have been synthesized based on nitrilotriacetic acid (H₃nta), like M(bpy)₂Cr₂(OH)₂(nta)₂·nH₂O, where M = Mn²⁺, Co²⁺, Ni²⁺ and Zn²⁺; bpy = α,α′- bipyridine; n = 8 or 9. Their chemical composition has been determined from the results of the elemental analysis and thermogravimetric study. The coordination modes of the nta3 ̄ ligand and the type of chemical bonds have been proposed basing on IR spectra.


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DOI: dx.doi.org/10.19261/cjm.2006.01(1).06

Graphical Abstract: A lasting economy of the state requires continuous progress in technology based on novel scientific achievements. Science and innovation are the basic factors ensuring competitiveness of our industry and agriculture and provide for about 50-85% of economic growth. Science is the nation’s patrimony and it determines the future of the country. The objectives of Science in Moldova are: - to get new knowledge about nature and society; - to create a wide scientific-technologic basis that would ensure: (1) innovation activity in the country; (2) technology progress; (3) world competitiveness of our production.


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DOI: dx.doi.org/10.19261/cjm.2006.01(1).09

Graphical Abstract: The novel bis(μ3-oxo) tetranuclear trichloracetate cluster, [Fe₄O₂(CCl₃COO)₈(THF)₂(DMF)(H₂O)]⋅THF (1), has been synthesised and subsequently characterised by X-ray structure analysis, magnetic measurements and infra red (IR). The structure of cluster is “butterfly” type. The Fe···Fe separation has the value of 2.883(1) - 3.441(7) Å. The coordination number of iron (III) is 6. Magnetic studies reveal the presence of an antiferromagnetic exchange in the parallelogram skeletons of the tetranuclear species. Using the spin Hamiltonian H = -2Jwb(Ŝ1Ŝ2 + Ŝ2Ŝ3 + Ŝ3Ŝ4 + Ŝ4Ŝ1) - 2JbbŜ2Ŝ4v+ gμβ(Ŝ1z + Ŝ2z +Ŝ3z + Ŝ4z)B, the fitting parameters Jbb = - 14.3 cm-1, Jwb = - 32.1 cm-1 , g = 2.07, ρparam. -5 impur. = 4.2 %, ΘCurie-Weiss const. = -0.5 K and R = 6.8·10 were obtained.

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DOI: dx.doi.org/10.19261/cjm.2006.01(1).10

Graphical Abstract: Literature data on utilization of acetyl group of aryl-1-ethanones (acetophenones) for the synthesis of organic compounds is generalized. Different approaches of preparation of aromatic compounds by chemical transformations of methyl as well as keto- group of titled compounds are systematized. Examples of the synthesis of organic compounds based on products of primary transformations of aryl-1-ethanones are considered.

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