Gan-Qing Zhao

Synthesis, Structures, and Antimicrobial Activity of Schiff Base Zinc Complexes with Thiocyanate and Iodide

The Schiff base N, N-dimethyl-N′-(1-pyridin-2-ylethylidene)-ethane-1,2-diamine (L) derived from 2-acetylpyridine and N, N-dimethylethane-1,2-diamine, and its zinc(II) complexes: [ZnL(NCS)2] and [ZnLI2], have been prepared and characterized by elemental analyses, IR, and single crystal X-ray crystallographic determination. The Schiff base coordinates to the Zn atom through the three N atoms. Each Zn atom adopts a trigonal-bipyramidal coordination. The effect of these complexes on the antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans were studied.

Synthesis, structure, and antimicrobial activity of a cadmium(II) complex derived from N,N′-bis(5-chlorosalicylidene)propane-1,3-diamine

The Schiff base, N,N′-bis(5-chlorosalicylidene)propane-1,3-diamine (H2L) derived from 5-chlorosalicylaldehyde and propane-1,3-diamine, and its cadmium(II) complex, bis(μ2-acetato)bis(μ2-N,N′-bis(5-chlorosalicylidene)-1,3-propanediamine)tricadmium(II) Cd[Cd(CH3COO)L]2 (I), have been prepared and characterized by elemental analyses, IR, and single-crystal X-ray diffraction analysis. The crystal of H2L is monoclinic: space group P21/n, a = 11.252(4), b = 8.972(3), c = 16.981(6) Å, β = 96.005(4)°, V = 1705.0(10) Å3, Z = 4. The crystal of complex I is monoclinic: space group P21/c, a = 11.056(1), b = 22.284(2), c = 8.398(1) Å, β = 91.779(1)°, V = 2068.0(3) Å3, Z = 2. Complex I is a centrosymmetric trinuclear cadmium(II) complex. The deprotonated Schiff base ligand coordinates to the Cd atoms through the phenolate O and imine N atoms. The effect of the Schiff base ligand and the complex on the antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans was studied.

Synthesis, structures, and antimicrobial activity of nickel(II) and Zinc(II) complexes with 5-methoxy-2-[(3-methylaminopropylimino)methyl]phenol

The Schiff base 5-methoxy-2-[(3-methylaminopropylimino)methyl]phenol (MMP) derived from 4-methoxysalicylaldehyde and N-methylpropane-1,3-diamine and its nickel(II) and zinc(II) complexes [Ni(MMP)2(NCS)2] (I) and [ZnCl2(MMP)] (II), have been prepared and characterized by elemental analyses, IR, and single crystal X-ray crystallographic determination. The crystal of I is monoclinic: space group P21/c, a = 9.0488(8), b = 12.7768(12), c = 12.9232(11) Å, β = 101.927(5)°, V = 1461.9(2) Å3, Z = 2. The crystal of II is orthorhombic: space group Pbca, a = 11.6991(7), b = 13.2839(8), c = 20.4451(12) Å, V = 3177.4(3) Å3, Z = 8. The Schiff base coordinates to the metal atoms through the phenolate O and imine N atoms. The effect of these complexes on the antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans were studied.

Synthesis, structures, and biological activity of terbium(III) and cobalt(III) complexes derived from tripodal Schiff bases

Terbium(III) (I) and cobalt(III) (II) complexes derived from tripodal Schiff bases tris(2-((5-chlorosalicylidene)amino)ethyl)amine (H3La) and tris(2-((4-methoxysalicylidene)amino)ethyl)amine (H3Lb), respectively, have been prepared and characterized by elemental analyses, IR, and single crystal X-ray crystallographic determination (CIF files CCDC nos. 1021371 (I) and 1021372 (II)). The crystal of [Tb(La)3] (I) is monoclinic: space group P21/n, a = 12.689(1), b = 15.301(1), c = 15.099(1) Å, β = 110.484(2)°, V = 2746.2(4)Å3, Z = 4, R1 = 0.0314, wR2 = 0.0801. The crystal of [Co(Lb)3)]2 · MeCN (II) is triclinic: space group

Manganese(III) complexes derived from bis-Schiff bases: Synthesis, structures, and antimicrobial activity

P\bar 1

Two New Schiff-Base Copper(II) and Nickel(II) Complexes: Synthesis, Structures, and Antimicrobial Activities

, a = 12.3031(6), b = 13.7209(7), c = 17.884(1) Å, α = 83.785(2)°, β = 88.144(2)°, γ = 87.873(1)°, V = 2998.0(3) Å3, Z = 2, R1 = 0.0669, wR2 = 0.1538. The tripodal Schiff base ligands coordinate to the metal atoms through three phenolate O and three imine N atoms. The Tb atom in complex I is in a monocapped octahedral coordination, and the Co atom in complex II is in octahedral coordination. The effects of the complexes on the antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans were studied.

Synthesis, structures, and antimicrobial activity of nickel(II) and zinc(II) complexes with Schiff bases derived from 3-bromosalicylaldehyde

The Schiff base N-isopropyl-N′-(1-pyridin-2-ylethylidene) ethane-1,2-diamine (L) derived from 2-acetylpyridine and N-isopropylethane-1,2-diamine, and its mononuclear zinc(II) and polymeric copper(II) complexes, [ZnL(NCS)2] and [CuL(μ 2-NCS)] n ·nBF4, have been prepared and characterized by elemental analyses, IR, and single-crystal X-ray crystallographic determination. The Schiff base coordinates to the metal atoms through the three N atoms. The Zn atom in [ZnL(NCS)2] adopts a trigonal-bipyramidal coordination, and the Cu atom in [CuL(μ 2-NCS)] n ·nBF4 adopts a square-pyramidal coordination. The effect of the complexes on the antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans were studied.

N'-(3-Bromo-5-chloro-2-hydroxy-benzyl-idene)-4-hydr-oxybenzohydrazide.

Manganese(III) complexes derived from the bis-Schiff bases N,N′-bis(5-fluorosalicylidene)-1,2-diaminoethane (H2La) and 3,4-bis(2-hydroxybenzylideneamino)pyridine (H2Lb), respectively, have been prepared and characterized by elemental analyses, IR, and single crystal X-ray crystallographic determination (CIF files CCDC nos. 997243 (I), 995896 (II)). The crystal of [MnLa(μ1,3-N3)]n (I) is orthorhombic: space group Pca21, a = 10.723(1), b = 13.430(1), c = 11.112(1) Å, V = 1600.2(2) Å3, Z = 4, R1 = 0.0264, wR2 = 0.0649. The crystal of [MnLb(N3)(CH3OH)] (II) is monoclinic: space group C2/c, a = 22.792(1), b = 14.4442(7), c = 12.8637(6) Å, β = 119.262(1)°, V = 3694.5(3) Å3, Z = 8, R1 = 0.0367, wR2 = 0.0776. The bis-Schiff base ligands coordinate to the metal atoms through phenolate O and imine N atoms. Each metal atom in the complexes is in octahedral coordination. The effects of the complexes on the antimicrobial activity against Staphylococcus aureus, Escherichia coli, and Candida albicans were studied.