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1.
Turk J Chem ; 45(5): 1463-1475, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34849060

RESUMO

The catalysts comprising the main active compounds of Sn-Nx were synthesized using trichlorophenylstannane ((C6H5)Cl3Sn), nitrogen carbon-dots (NCDs), and activated carbon (AC) as starting materials, and the activity and stability of catalysts was evaluated in the acetylene hydrochlorination. According to the results on the physical and chemical properties of catalysts (TEM, XRD, BET, XPS and TG), it is concluded that NCDs@AC can increase (C6H5)Cl3Sn dispersity, retard the coke deposition of (C6H5)Cl3Sn/AC and lessen the loss of (C6H5)Cl3Sn, thereby further promoting the stability of (C6H5)Cl3Sn/AC. Based on the characterization results of C2H2-TPD and HCl adsorption experiments, we proposed that the existence of Sn-Nx can effectively strengthen the reactants adsorption of catalysts. By combing the FT-IR, C2H2-TPD and Rideal-Eley mechanism, the catalytic mechanism, in which C2H2 is firstly adsorbed on (C6H5)Cl3Sn to form (C6H5)Cl3Sn-C2H2 and then reacted with HCl to produce vinyl chloride, is proposed.

2.
Acta Chim Slov ; 68(1): 17-24, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-34057531

RESUMO

Three new zinc(II) complexes, [Zn2I2(L1)2] (1), [Zn(HL2)2(NCS)2] (2), and [ZnIL3] (3), where L1 is the anionic form of 2-[(6-methylpyridin-2-ylimino)methyl]phenol (HL1), HL2 is the zwitterionic form of 2-(cyclopropyliminomethyl)-5-fluorophenol (HL2), and L3 is the anionic form of 5-bromo-2-[(3-morpholin-4-ylpropylimino)methyl]phenol (HL3), have been prepared and characterized by elemental analyses, IR, UV and NMR spectra, and single crystal X-ray crystallographic determination. Complex 1 is a dinuclear zinc complex, and complexes 2 and 3 are mononuclear zinc complexes. The Zn atoms in the complexes are in tetrahedral coordination. The effect of the complexes on the antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans were evaluated.


Assuntos
Antibacterianos/farmacologia , Antifúngicos/farmacologia , Complexos de Coordenação/farmacologia , Bases de Schiff/farmacologia , Antibacterianos/síntese química , Antifúngicos/síntese química , Candida albicans/efeitos dos fármacos , Complexos de Coordenação/síntese química , Escherichia coli/efeitos dos fármacos , Testes de Sensibilidade Microbiana , Bases de Schiff/síntese química , Staphylococcus aureus/efeitos dos fármacos , Zinco/química
3.
Int J Mol Sci ; 21(6)2020 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-32168957

RESUMO

Micronutrient deficiencies, and especially zinc (Zn) deficiency, pose serious health problems to people who mainly depend on cereal-based diets. Here, we performed a genome-wide association study (GWAS) to detect the genetic basis of the Zn accumulation in wheat (Triticum aestivum L.) grains with a diversity panel of 207 bread wheat varieties. To uncover authentic quantitative trait loci (QTL) controlling Zn accumulation, the varieties were planted in three locations. In total, 29 unique loci associated with Zn grain accumulation were identified. Notably, seven non-redundant loci located on chromosomes 1B, 3B, 3D, 4A, 5A, 5B, and 7A, were detected at least in two environments. Of these quantitative trait loci (QTL), six coincided with known QTL or genes, whereas the highest effect QTL on chromosome 3D identified in this study was not reported previously. Searches of public databases revealed that the seven identified QTL coincided with seven putative candidate genes linked to Zn accumulation. Among these seven genes, NAC domain-containing protein gene (TraesCS3D02G078500) linked with the most significant single nucleotide polymorphism (SNP) AX-94729264 on chromosome 3D was relevant to metal accumulation in wheat grains. Results of this study provide new insights into the genetic architecture of Zn accumulation in wheat grains.


Assuntos
Locos de Características Quantitativas , Triticum/genética , Zinco/metabolismo , Mapeamento Cromossômico , Cromossomos de Plantas/genética , Estudo de Associação Genômica Ampla , Genótipo , Melhoramento Vegetal , Polimorfismo de Nucleotídeo Único , Triticum/metabolismo
4.
Acta Chim Slov ; 67(1): 187-194, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33558941

RESUMO

Two copper(II) complexes, [CuL2(EA)] (1) and [Cu2L4(PA)2]·2H2O (2·2H2O), where L is 1-naphthylacetate, EA is N,N-diethylethane-1,2-diamine, PA is propane-1,3-diamine, have been prepared and characterized. Structures of the complexes have been characterized by single-cyrstal X-ray diffraction. Complex 1 is a mononuclear copper(II) compound, with the Cu atoms coordinated in square planar geometry. Complex 2·2H2O is a centrosymmetric dinuclear copper(II) compound, with the Cu atoms coordinated in square pyramidal geometry. Single crystals of the complexes are stabilized by hydrogen bonds. The effects of the compounds on the antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans, as well as thermal behavior of the complexes were studied.

5.
Acta Chim Slov ; 64(2): 500-505, 2017 06.
Artigo em Inglês | MEDLINE | ID: mdl-28621393

RESUMO

Two mononuclear Schiff base manganese(III) complexes, [MnL(N3)(OH2)]·CH3OH (1) and [MnL(NCS)(OH2)] · H2O (2), where L is the dianionic form of N,N'-bis(5-nitrosalicylidene)ethane-1,2-diamine, have been prepared and characterized by elemental analysis, IR and UV-Vis spectroscopy and single crystal X-ray diffraction. The Mn atom in each complex is in an octahedral coordination. Molecules of the complexes are linked through intermolecular hydrogen bonds. Catalytic properties for epoxidation of styrene by the complexes using PhIO and NaOCl as oxidant have been studied.

6.
Acta Crystallogr Sect E Struct Rep Online ; 67(Pt 2): m173-4, 2011 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-21522850

RESUMO

The asymmetric unit of the title compound, {[Cu(C(13)H(15)NO(3))(C(5)H(8)N(2))]·CH(3)OH}(n), contains two complex mol-ecules and two solvent mol-ecules. Each Cu(II) ion is in a distorted square-pyramidal coordination with one N and two O atoms from the Schiff base ligand and one N atom from the heterocycle in the basal positions and one carboxyl-ate O atom from a neighbouring ligand in the apical position. The apical Cu-O bonds are much longer than the basal Cu-O and Cu-N bonds. The carboxyl-ate groups of the Schiff base ligands bridge the Cu(II) ions, forming helical chains along [100]. The crystal packing is stabilized by inter-molecular O-H⋯O and N-H⋯O hydrogen bonds.

7.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 10): m1274, 2010 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-21587418

RESUMO

In the title complex, [Cu(NCS)(2)(C(12)H(19)N(3))], the Cu(II) atom is five-coordinated in a square-pyramidal geometry defined by one pyridine N, one imine N, and one amine N atom of the tridentate Schiff base ligand and two N-bonded thio-cyanate ions (one of the latter occupying the apical site). The three bridging C atoms and the two terminal C atoms of the Schiff base are disordered over two sets of sites, with occupancies of 0.465 (2) and 0.535 (2).

8.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 9): m1127-8, 2010 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-21588530

RESUMO

In either of the two independent mol-ecules within the asymmetric unit of the title compound, [Ni(C(16)H(15)NO(3))(C(3)H(4)N(2))], the Ni(II) atom is coordinated by the two N atoms and two O atoms in a distorted square-planar geometry. The crystal packing is stabilized by strong and weak inter-molecular C-H⋯O hydrogen bonds, as well as weak centroid-centroid π-stacking inter-actions [centroid-centroid separation = 3.526 (3) Å].

9.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 9): m1172-3, 2010 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-21588561

RESUMO

In the title thio-cyanate-bridged polynuclear copper(II) complex, [Cu(C(10)H(12)NO(3))(NCS)](n), the Cu atom is five-coordinated in a square-pyramidal geometry, with one phenolato O, one imino N and one hy-droxy O atom of a Schiff base ligand and one thio-cyanato N atom defining the basal plane, and with one thio-cyanato S atom occupying the apical position. In the crystal structure, pairs of adjacent complex mol-ecules are linked through inter-molecular O-H⋯O hydrogen bonds into dimers. The dimers are further linked via Cu⋯S inter-actions, forming two-dimensional layers parallel to the bc plane.

10.
Acta Crystallogr Sect E Struct Rep Online ; 66(Pt 11): m1352, 2010 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-21588797

RESUMO

The asymmetric unit of the title complex, [Ni(NCS)(2)(C(13)H(20)N(2)O(2))(2)], consists of two half-mol-ecules, both of which are completed by crystallographic inversion symmetry (Ni(2+) site symmetry = in both cases). Both metal ions are six-coordinated in distorted trans-NiO(2)N(4) geometries arising from two N,O-bidentate Schiff base ligands and two N-bonded thio-cyanate ions. The mol-ecular conformations are reinforced by two intra-molecular N-H⋯O hydrogen bonds.

11.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 10): m1212-3, 2009 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-21577738

RESUMO

In the title compound, [Cu(C(15)H(11)N(3)O(3))(C(10)H(8)N(2))], the Cu(II) atom is five-coordinated in a distorted square-pyramidal CuN(3)O(2) geometry. The basal positions are occupied by three donor atoms from the tridentate Schiff base ligand and by one N atom from the 2,2'-bipyridine ligand. The axial position is occupied by the other N atom of the 2,2'-bipyridine ligand. The crystal structure is consolidated by weak C-H⋯O hydrogen bonds. In addition, π-π inter-actions between adjacent pyridine rings (centroid-centroid distances = 3.238 and 3.313 Å) may also stabilize the crystal packing.

12.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 10): m1237, 2009 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-21577755

RESUMO

In the title compound, [Cu(C(13)H(9)NO(3))(C(5)H(5)N)], the Cu(II) atom is coordinated in a distorted square-pyramidal geometry, with two N and two O atoms in the basal positions and one O atom in the apical position. The apical Cu-O bond [2.3520 (16) Å] is much longer than the basal Cu-O and Cu-N bonds [1.9139 (14)-2.0136 (17) Å]. The carboxyl-ate group bridges Cu(II) atoms, forming a zigzag chain along the a axis.

13.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 11): m1427, 2009 Oct 23.
Artigo em Inglês | MEDLINE | ID: mdl-21578163

RESUMO

In the title compound, [Cu(C(8)H(7)O(2))(NO(3))(C(10)H(8)N(2))], the Cu(II) ion is five-coordinate in a distorted square-pyramidal geometry. The basal positions are occupied by two N atoms from a 2,2'-bipyridine ligand and two O atoms from the 2-acetyl-phenolate anion. The axial position is occupied by one O atom of a nitrate anion. In the bipyridine ligand, the two pyridine rings are slightly twisted by an angle of 3.5 (1)°. The crystal structure is stabilized by C-H⋯O hydrogen bonds.

14.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 11): o2853, 2009 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-21578442

RESUMO

In the title compound, C(22)H(16)N(2)OS(2), the phenanthrene ring is nearly perpendicular to the phenyl ring, making a dihedral angle of 87.2 (2)°. Intra-molecular N-H⋯O inter-actions are present. In the crystal structure, the mol-ecules are linked through inter-molecular C-H⋯O inter-actions. The crystal structure is also stabilized by C-H⋯π inter-actions and weak π-π contacts [centroid-centroid distance = 3.36 (6) Å].

15.
Acta Crystallogr Sect E Struct Rep Online ; 65(Pt 12): m1505, 2009 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-21578556

RESUMO

In the title compound, [Cu(C(11)H(11)NO(4))(H(2)O)]·H(2)O, each Cu(II) ion is four-coordinated by one N and two O atoms from the tridentate Schiff base ligand, and by one O atom from the coordinated water mol-ecule in a distorted square-planar geometry. Inter-molecular O-H⋯O hydrogen bonds link complex mol-ecules and solvent water mol-ecules into flattened columns propagated in [100].

16.
Artigo em Inglês | MEDLINE | ID: mdl-18343716

RESUMO

The solid phase FT-IR and FT-Raman spectra of 1-[6-(4-chlorophenyl)-1-[(6-chloropyridin-3-yl)methyl]-2-[(6-chloropyridin-3-yl)methylsulfanyl]-4-methyl-1,6-dihydropyrimidin-5-yl]ethanone (C25H21Cl3N4OS) were recorded in the region 4000-400 and 3500-100cm(-1), respectively. The vibrational spectra have been computed using density functional theory (B3LYP) and ab initio molecular orbital calculation (HF) with 6-31G(d, p) basis sets. A close agreement was achieved between the observed and calculated frequency by employing normal coordinate calculations. The observed and simulated spectra were found to be well comparable.


Assuntos
Modelos Químicos , Piridinas/química , Pirimidinas/química , Vibração , Cristalografia por Raios X , Modelos Moleculares , Estrutura Molecular , Espectrofotometria Infravermelho , Análise Espectral Raman
17.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 10): m1228, 2008 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-21200988

RESUMO

In the title compound, [Cu(C(17)H(15)NO(3))(C(3)H(4)N(2))], the Cu(II) atom is four-coordinated by two O atoms and the N atom of the tridentate Schiff base ligand, and one N atom from the imidazole ligand in a distorted square-planar geometry. In the crystal structure, mol-ecules are linked into dimers by inter-molecular N-H⋯O hydrogen bonds.

18.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 10): m1250-1, 2008 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-21201007

RESUMO

In each of the two independent mol-ecules in the asymmetric unit of the title compound, [Cu(C(13)H(15)NO(3))(C(3)H(4)N(2))], the Cu(II) atom is four-coordinated by two O atoms and the N atom of the tridentate Schiff base ligand and one N atom from the imidazole ligand in a distorted square-planar geometry. In the crystal structure, mol-ecules are linked by inter-molecular N-H⋯O hydrogen bonds.

19.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 10): o1938, 2008 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-21201145

RESUMO

The mol-ecule of the title compound, C(14)H(10)BrClN(2)O(3), is planar [dihedral angle between the aromatic rings = 3.0 (2)°] and shows a trans configuration with respect to the C=N double bond. The crystal structure is stabilized by inter-molecular N-H⋯O hydrogen bonds and an intramolecular O-H⋯N interaction also occurs.

20.
Acta Crystallogr Sect E Struct Rep Online ; 64(Pt 12): m1553, 2008 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-21581163

RESUMO

In the title compound, [Cu(C(11)H(11)NO(3))(C(11)H(16)N(4))]·H(2)O, the Cu(II) atom is five-coordinate in a distorted square-pyramidal geometry. The basal positions are occupied by three donor atoms from the tridentate Schiff base ligand and by one N atom from a bis-(3,5-dimethyl-prazol-l-yl)methane ligand. The apical position is occupied by the N atom of the other ligand of this type. There are only van der Waals contacts in the crystal structure.

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