Xiang-Fei Chen

Synthesis, structure, urease inhibitory, and cytotoxic activities of two complexes with protocatechuic acid derivative and phenanthroline

Two complexes, [CuII(L1)(phen)2](ClO4) (1) and [NiII2(L1)2(phen)2(MeOH)2](ClO4)2 (2), with HL1, a ligand derived from protocatechuic acid (=2,3-dihydrobenzo[b][1,4]dioxine-6-carboxylic acid) and phen (=1,10-phenanthroline) were synthesized and characterized by C, H, and N elemental analysis, UV–vis, FT-IR, and single-crystal X-ray diffraction, which revealed that 1 is mononuclear and 2 is dinuclear. Both complexes crystallized in monoclinic space group C2/c. The urease inhibitory activity and in vitro cytotoxic activity of 1 and 2 were tested. The complexes showed strong inhibitory activity against jack bean urease and significantly suppressed the growth of A549, L929, and SW620 cell lines.

Structure and urease inhibitory activity of copper(II) complex with (E)-3-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)acrylic acid

A new caffeic acid derivative ((E)-3-(2,3-dihydrobenzo[b][1,4]dioxin-6-yl)acrylic acid, HL1)) is synthesized from caffeic acid, followed by the preparation of a Cu(II) complex, [Cu2(L1)4DMSO2]·2DMSO. The structure is determined by single crystal X-ray diffraction, and the urease inhibitory activity of the complex is studied. The results show that IC50 of the complex is 0.56 μmol/L, which is superior to positive control acetohydroxamic acid (AHA, IC50 was 10.95 μmol/l), i.e., the complex has strong inhibitory activity towards urease.

Synthesis, structure, and urease inhibitory activities of Co(III), Mn(II) and Zn(II) complexes with hydrazone derived from protocatechuic acid

Abstract [CoIII(L1)2·H2O]NO3 (1), [MnII(L1)2·H2O] (2), and [ZnII(L1)2·H2O] (3) with a hydrazone derived from protocatechuic acid (HL1 = C15H13N3O3) were designed, synthesized, and characterized by C, H, N elemental analyses, single-crystal X-ray diffraction, and IR spectra, which revealed that the three complexes are similar structures. Docking study has been done. The urease inhibitory activities of the three complexes were tested. Complexes 1 and 3 showed strong inhibitory activity against jack bean urease with IC50 values of 45.9 and 11.64 μM. Complex 2 had no obvious inhibitory activity to urease; the IC50 was > 50 μM.

Characterization and X-Ray Structures of Oxovanadium(V) Complexes Derived from Hydrazone Ligands

The reaction of [VO(acac)2] (where acac = acetylacetonate), benzohydroxamic acid (HL) with N′-(3,5-dichloro-2-hydroxybenzylidene)nicotinohydrazide (H2L1) and N′-(2-hydroxy-4-methoxybenzylidene)-3-nitrobenzohydrazide (H2L2) in methanol affords methanol-coordinated mononuclear oxovanadium(V) complexes [VOL1L] (1) and [VOL2L]·MeOH (2), respectively. Crystal and molecular structures of the complexes are determined by the single crystal X-ray diffraction method. The complexes were further characterized by the elemental analysis and FT-IR spectra. Single crystal X-ray structural studies indicate that the hydrazone ligands coordinate to the VO core through enolate oxygen, phenolate oxygen, and azomethine nitrogen atoms, and the benzohydroxamate ligands coordinate to the VO core through the carbonyl oxygen and hydroxy oxygen atoms. The V atoms in the complexes are in the octahedral coordination. The thermal stability of the complexes are also studied.

Synthesis, characterization, and biological activities of a Cu(II) complex with the non-steroidal antiinflammatory drug flufenamic acid

Abstract [CuII(L)2.C12H10N2] with flufenamic acid (HL=C14H10F3NO2) and phenanthroline (C12H10N2O) was synthesized and characterized by C, H and N elemental analysis, single-crystal X-ray diffraction and, IR spectra. The urease inhibitory and antibacterial activities of the complex were tested. The complex showed strong inhibitory activity against jack bean urease with an IC50 value of 0.265 μM. Four bacteria, Bacillus subtilis, Escherichia coli, Staphylococcus aureus, and proteusbacillus vulgaris, were used in the antibacterial test. The complex showed strong inhibitory activity against the species with IC50 values of 2.016, 35.037, 10.680, and 3.820 μM. The interactions of the complex with human serum albumin (HSA) were studied through fluorescence spectroscopy. By analyzing the experimental data, we concluded that the fluorescence quenching mechanism of the complex with serum albumin was static quenching. The binding mode of the complex with DNA through UV spectroscopy was electrostatic binding or groove.

Syntheses, characterization and crystal structures of [Ni(La)2] and [Zn(Lb)(N3)(Amp)]

A new centrosymmetric mononuclear nickel(II) complex, [Ni(La)2] (I), and a new mononuclear zinc(II) complex, [Zn(Lb)(N3)(AMP)] (II) (La = 2-iminomethyl-4-methylphenolate, Lb = 4-methyl-2-[(4-methylpyridin-2-ylimino)methyl]phenolate, AMP = 2-amino-4-methylpyridine), have been prepared and characterized by elemental analysis, IR and UV-Vis spectra, and single-cyrstal X-ray diffraction (CIF files CCDC nos. 1059023 (I) and 1059024 (II)). Complex I crystallizes in the monoclinic space group P21/c with unit cell dimensions a = 16.067(2), b = 5.7222(6), c = 7.9004(9) Å, β = 92.471(4)°, V = 725.7(1) Å3, Z = 2, R1 = 0.0298, and wR2 = 0.0695. Complex II crystallizes in the triclinic space group

Synthesis, Crystal Structures and Urease Inhibition of N'-(2-Bromobenzylidene)-2-(4-nitrophenoxy) acetohydrazide and N'-(4-Nitrobenzylidene) -2-(4-nitrophenoxy)acetohydrazide.

P\bar 1

Synthesis and X-ray structures of di- and mono-nuclear oxovanadium(V) complexes derived from aroylhydrazones

with unit cell dimensions a = 7.649(1), b = 10.414(2), c = 13.903(3) Å, α = 106.896(2)°, β = 91.581(2)°, γ = 103.033(2)°, V = 1027.3(4) Å3, Z = 2, R1 = 0.0372, and wR2 = 0.0823. The Ni atom in I is in a square planar coordination, and the Zn atom in II is in a tetrahedral coordination. Crystals of the complexes are stabilized by hydrogen bonds and p···p interactions.