Chemistry Journal of Moldova

2008 Volume 3, no.2

ISOLATION OF ENT-KAUR-16-EN-19-OIC AND ENT-TRACHILOBAN-19-OIC ACIDS FROM THE SUNFLOWER HELIANTHUS ANNUUS L.DRY WASTE

Author(s):

Nicon Ungur, Marina Grinco, Veaceslav Kulciţki, Alic Barba, Tatiana Bîzîcci, Pavel F. Vlad


Field: Natural product chemistry and synthesis
Type: Research paper
Issue: 2008 Volume 3, no.2
Pages: 105-108
Keywords: ent-kaur-16-en-19-oic acid, ent-trachiloban-19-oic acid, diterpene, isolation.
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Abstract (JPEG)

DOI:
dx.doi.org/10.19261/cjm.2008.03(2).01

Graphical Abstract:
 A relatively simple method for isolation of the mixture of ent-kaur-16-en-19-oic (1) and ent-trachiloban-19-oic (2) acids from dry waste of sunflower processing has been elaborated, and it has been shown that the waste can serve as an accessible source of ent-kauranic and ent-trachilobanic diterpenoids.

Downloads: 19

AB INITIO STUDY OF THE POSSIBLE SINGLE-CENTER UNITS FOR BINUCLEAR IRON COMPLEX [Fe2(bpym)3Cl4]

Author(s):

Tihonovschi Andrei


Field: Physical chemistry and chemical physics
Type: Research paper
Issue: 2008 Volume 3, no.2
Pages: 114-118
Keywords: iron complexes, bipyrimidine complexes, magnetic properties, ab initio study.
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DOI:
dx.doi.org/10.19261/cjm.2008.03(2).02

Graphical Abstract:
 In present work we study two possible single-center units for binuclear iron complex Fe2(bpym)3Cl4 –[Fe(bpym)3]2+ and Fe(bpym)2Cl2. The obtained ground states for both studied systems are singlet states. In the case of Fe(bpym)2Cl2 the lowest excited states were calculated to be 240cm-1 (triplet) and 660cm-1 (quintet) above the ground state and so are placed according to Lande rule. These states could be populated at room temperatures. For [Fe(bpym)3]2+ first excited state was found to be about 6000cm-1 above the ground state and so cannot be populated at normal temperatures.

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SHELF-LIFE PREDICTION OF PLUM FOODS USING ANTIOXIDANT ACTIVITY INDICES

Author(s):

Pavel Gh.Tatarov, Raisa A. Ivanova, Artur V. Macari


Field: Food chemistry
Type: Research paper
Issue: 2008 Volume 3, no.2
Pages: 65-69
Keywords: shelf-life, antioxidant activity, Weibull distribution, plum, chokeberry.
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DOI:
dx.doi.org/10.19261/cjm.2008.03(2).03

Graphical Abstract:
 The reducing activity and radical scavenging activity of hydrosoluble antioxidants in food compositions from plums during the storage were evaluated. The speeds of changing the reducing activity and radical scavenging activity were different. It was observed that the reducing activity diminished by 63.2% after 62...105 days of storage. The same modification of radical scavenging activity determined in vitro was discovered after 110...254 days of storage. Shelf-life of plum foods was calculated using Weibull distribution. The functional relationship of failure probabilities between the reducing and radical scavenging capacities have been detected (r2= 0. 94-0.98).

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MIXED-LIGANDS μ3-OXO TRINUCLEAR CARBOXYLATES [Fe3O(CH2BrCOO)1.5(CH2ClCOO)4.5(H2O)3]Br0.75Cl0.25 5H2O and [Fe3O(BrCH2COO)6(H2O)3] NO3⋅2.63H2O

Author(s):

Sergiu Shova, Ana Lazarescu, Maria Gdaniec, Yurii Simonov, Constantin Turta


Field: Inorganic and coordination chemistry
Type: Research paper
Issue: 2008 Volume 3, no.2
Pages: 86-94
Keywords: mixed-ligands complexes; Iron(III) carboxylates; crystal structure, magnetic properties.
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DOI:
dx.doi.org/10.19261/cjm.2008.03(2).04

Graphical Abstract:
Two novel μ3-oxo-centered carboxylate-bridged triiron complexes [Fe3O(BrCH2COO)6(H2O)3] NO3·2.63H2O (1) and [Fe3O(CH2BrCOO)1.5(CH2ClCOO)4.5(H2O)3]Br0.75Cl0.25 5H2O (2) were synthesized and their structures were characterized by X-ray crystallography. The opportunity of mixed-ligand complex formation in iron(III)-bromoacetic acid system was shown. The first co-ordination sphere of the iron atom in compound 2 includes two different carboxylate anions, CH2BrCOO- and CH2ClCOO- in the capacity of syn-syn- bidentate-bridged ligands, while Br- and Cl- anions being in the ratio 1:1, formulate the external sphere of the complex. The IR spectra, thermic analysis and magnetic properties of complexes were studied.

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SPECIFIC “IONIC LIQUIDS” AS NEW ORGANOCATALYSTS OF BIGINELLI REACTION

Author(s):

Viorica Sargarovschi, Eugenia Styngach, Fliur Macaev


Field: Natural product chemistry and synthesis
Type: Research paper
Issue: 2008 Volume 3, no.2
Pages: 95-97
Keywords: ionic liquids, organocatalyst, Biginelli reaction.
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DOI:
dx.doi.org/10.19261/cjm.2008.03(2).05

Graphical Abstract:
 New ionic liquids bearing an imidazolium core with a carboxy group have been prepared in an attempt to design new organocatalysts of Biginelli reaction. Trends in the properties of these compounds are discussed. The synthetized compounds represented a novel class of molted salts and may be considered as new organocatalysts for chemical reaction.

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CARBOXYLATE SUBSTITUTION PATTERN AS STRUCTURAL DIRECTIVE FOR THE FINAL PRODUCTS: SYNTHESIS, STRUCTURE AND PROPERTIES OF [Fe4Ca2O2(μ2-HCCl2COO)10(μ3-HCCl2COO)2(THF)6]

Author(s):

Denis Prodius, Valeriu Mereacre, Maria Gdaniec, Sergiu Shova, Yurii A. Simonov, Nicolae Stanica, Ion Geru, Andrea Caneschi, Constantin Turta


Field: Inorganic and coordination chemistry
Type: Research paper
Issue: 2008 Volume 3, no.2
Pages: 81-85
Keywords: Iron(III) calcium(II) heterocluster; crystal structure; antiferromagnetic interaction.
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Abstract (JPEG)

DOI: dx.doi.org/10.19261/cjm.2008.03(2).06

Graphical Abstract:
 A novel hexanuclear iron-calcium-oxo complex has been synthesized and characterized by different physico-chemical methods and X-ray single crystal structural analysis: [Fe4Ca2O2(μ2-HCCl2COO)10(μ3-HCCl2COO)2(THF)6].The molecular structure shows that there are two types of coordination for COO- anions: bidentate and tridentate.The corresponding variable temperature susceptibility measurement shows that in the complex there exists an antiferromagnetic interaction (|J12| = |J34| = -71.86 cm-1). The iron(III) high spin state (5/2) is proved by Mössbauer spectroscopy. High magnetic EPR measurements of 1 indicates the presence of S=0 ground state with low-lying S=1 excited state centred around g = 2.0054 ±0.0001.

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GLYCOSIDES FROM LINARIA VULGARIS MILL

Author(s):

Natalia Mashcenko, Pavel Kintia, Angela Gurev, Alexandra Marchenko, Carla Bassarello, Sonia Piacente, Cosimo Pizza


Field: Natural product chemistry and synthesis
Type: Research paper
Issue: 2008 Volume 3, no.2
Pages: 98-100
Keywords: Linaria vulgaris Mill; fl avonol glycoside; linaroside V; NMR analysis.
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DOI:
dx.doi.org/10.19261/cjm.2008.03(2).07

Graphical Abstract:
A new flavonol glycoside, 5,4′-dimethylkaempferol 3-O-β-D-(6′′-α-Lrhamnopyranosyl) -glucopyranoside, together with three known compounds were isolated from the n-butanolic soluble fraction of underground and aerial parts of Linaria vulgaris Mill, collected on the territory of Moldova. The characterisation of these compounds was achieved by various chromatographic and spectroscopic methods (IR, UV, 13C-NMR, 1H-NMR and MS).

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PHENYLETHANOID AND IRIDOID GLYCOSIDES FROM VERONICA CHAMAEDRYS L.

Author(s):

Alexandra Marchenko, Pavel Kintia, Natalia Mashcenco, Carla Bassarello, Sonia Piacente and Cosimo Pizza


Field: Natural product chemistry and synthesis
Type: Research paper
Issue: 2008 Volume 3, no.2
Pages: 101-104
Keywords: Veronica chamaedrys L., Scrophulariaceae, phenylethanoid glycoside, iridoid glycoside.
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DOI:
dx.doi.org/10.19261/cjm.2008.03(2).08

Graphical Abstract:
 Three phenylethanoid glycosides (1, 2, 3) and one iridoid glycoside (4) were isolated from aerial parts of Veronica chamaedrys L. (Scrophulariaceae) for the first time. On the basis of spectral analysis, the structures of these compounds were determined to be acteoside (3,4-dihydroxy-β-phenylethoxy-O-α-L-rhamnopyranosyl-(1→3)-4-O-caffeoyl-β-D-glucopyranoside) (1), ehrenoside (3,4-dihydroxy-β-phenylethoxy-O-α-L-arabinopyranosyl-(1→2)-α-L-rhamnopyranosyl-(1→3)-4-O-caffeoyl-β-D-glucopyranoside) (2), chamaedroside (3,4-dihydroxy-β-phenylethoxy-O-α-L-rhamnopyranosyl-(1→3)-4-O-caffeoyl-α-L-arabinopyranoside) (3) and aucuboside (4).

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ADSORPTION OF AMMONIA IONS AND AMMONIUM FROM AQUEOUS SOLUTIONS ON MODIFIED ACTIVATED CARBONS

Author(s):

T. Lupashcu, M. Ciobanu


Field: Ecological chemistry
Type: Research paper
Issue: 2008 Volume 3, no.2
Pages: 55-57
Keywords: adsorption, ammonia ion, ammonia and activated carbon.
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DOI:
dx.doi.org/10.19261/cjm.2008.03(2).09

Graphical Abstract:
 The adsorption process of ammonia ions and ammonium from aqueous solutions on the intact activated carbon obtained from nutshells through activation with phosphoric acid and oxidized with H2O2 and later impregnated with salt containing Co2+, Ag+, Ni2+, Cu2+, has been investigated. The efficiency of ammonia ions and ammonium elimination from various water categories, using both activated carbon (the intact CAN-7 and CAN-7 oxidized with H2O2 and impregnated with Co2+, Ag+, Ni2+, Cu2+ ions) has been demonstrated.

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SYNTHESIS OF PINONIC ACID NEW DERIVATIVES

Author(s):

Alexandru Gudima, Liudmila Vlad, Fliur Macaev


Field: Natural product chemistry and synthesis
Type: Short communication
Issue: 2008 Volume 3, no.2
Pages: 122-123
Keywords: pinonic acid, chlorohydrin, epoxide.
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DOI:
dx.doi.org/10.19261/cjm.2008.03(2).10

Graphical Abstract:
 The method for synthetising new derivatives of the pinonic acid using, at the key step, the reaction of condensation with epichlorohydrin, has been elaborated. It has been shown that, in the presence of catalytic amount of tetrabutylammonium chloride, the reaction is directed towards the formation of etherchlorohydrin, which, later on, is easily transformed into epoxides as well as chloromethyldiketones with good overall yield.

Downloads: 14