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Two uranyl complexes based on pyromellitic acid were hydrothermally synthesized, and their X-ray single-crystal diffraction structures were determined. Complex [UO2(Hbtec)]–(Himd)+·H2O (1) (H4btec = pyromellitic acid, imd = imidazole), is an ionic complex, which shows a typical (4, 4) topological structure in the space. A heterometallic complex, UO2Cu(btec)(phen) (2) (phen = 1,10-phenanthroline) results from the reaction of uranyl nitrate and copper(II) bromide with pyromellitic acid. The structure of complex 2 revealed that the chains of UO7 and CuO3N2 units were connected to each other through the carboxyl groups and U=O–Cu interactions to create a two-dimensional framework.

In an attempt to synthesize supra-molecular complex of copper (II) with mixed ligands in a solution reaction of Cu(ClO4)2· 6H2O with 4,5-diazafluorene-9-one (dafo) and o-phthalic add, the bright blue column-like crystal [Cu(dafo)2(H2O)2]-(ClO4)2 was obtained. Its structure was determined by single-crystal X-ray diffraction study. The crystal belongs to monoclinic system, space group P2(1)/n with cell dimensions: a = 0.7547(3) nm, b = 1.2021(5) nm, c = 1.3190(5) nm, α = 90.000(5)°, β = 90.000(5)°, γ = 90.000(5)°, V = 1.2600(9) nm3, Z = 2, F(000)=670, Mr = 662.83, Dc = 1.747 g/cm3, μ (Mo Kα) = 1.154 mm−1, R1, = 0.0455, wR2 = 0.1041. The analysis of the crystal structure indicates that the complex has a two-dimensional network structure which is formed by hydrogen bonds.

A novel one-dimensional chain complex [Zn(dafo)2(H2O)2](NO3)2 was obtained when we tried synthesizing a mixed ligand supramolecular compound of Zinc(II) with dafo and o-phthalic acid. Its structure was determined by single-crystal X-ray diffraction analysis. The crystal belongs to triclinic system, P-1 space group. The crystallographic data: a=0.6989(4) nm, b=0.8281(5) nm, c=1.0231(5) nm, α=94.934(5)°, β=91.366(7)°, γ=99.820(7)°, V=0.5809(5) nm3, Z= 1, F(000)=300, Mr=589.78, Dc=1.686 g/cm3, μ(Mo Kα)=1.130 mm−1, R1=0.0521, wR2=0.1096. The analysis of the crystal structure indicates that the compound has a one-dimensional chain structure which is formed by hydrogen bonds. The constitutes of the title complex were proved by elemental analysis, IR spectra and thermal analysis. On the basis of the experimentation, the complex was calculated by DFT-B3LW/LANL2DZ in Gaussian-98w also.

In an attempt to synthesize a new pyrimidine complex of copper(II) in a solution reaction of CuBr2 with 2,2′-bis(hexahydropyrimidine) and hydro-chloric acid, we unexpectedly obtained a bright yellow chip-like crystal of CuC4(H2tn) [H,tn=(H3NCH2CH2CH2NH3)2+]. Its structure was determined by single-crystal X-ray diffraction analysis. The crystal belongs to orthorhombic system, space group Pnma, with cell parameters: a=0.7216(2) nm, b= 1.8308(6) nm, c=0.7553(3) nm, V=0.9953(6) nm3, Z=4, F(000)=564, Mr=281.49, D,= 1.879 g/cm3. μ(Mo Ka)=3.204 m−1, R1=0.0248, wR2=0.0575. The analysis of the crystal structure indicates that the complex has a three-dimensional network structure, which is formed by hydrogen bonds and electrostatic interaction.

Two new multi-nuclear homometallic complexes, [Cu2(OAc)4(H2O)2]·2dafo (1) and [(µ2-O)2-Co3(dafo)6]-(ClO3)2·H2O (2) (dafo=4,5-diazafluoren-9-one), were synthesized. The two complexes have been fully characterized by elemental analysis, IR, absorption spectra, emission spectra, and single-crystal X-ray diffraction analysis. The initial DNA binding mechanisms of the two complexes have been investigated by absorption spectra, emission spectra and cyclic voltammograms. Both complexes show similar perturbations on addition of calf thymus DNA in the UV region, their luminescence intensities in aqueous buffer are all enhanced in the presence of increasing amounts of DNA, and their electrochemical behavior is both completely different in the absence and presence of DNA. The results of the three methods indicate that the spectral characters and the electrochemical behavior of the two complexes are very similar to those of the known metallointercalators. So it can be concluded that the action mode of the two complexes with DNA is mainly intercalative.

Two new complexes [Cu(dafo)2(en)](ClO4)2·2H2O (en=NH2CH2CH2NH2) 1 and [Cu(dafo)2(dap)](ClO4)2· 2H2O [dap=NH2CH2CH(CH3)NH2] 2 (dafo=4,5-diazafluoren-9-one) have been synthesized and characterized by elemental analysis, IR and UV spectra. Meanwhile, the complex 1 has been characterized by single crystal X-ray diffraction analysis. The initial DNA binding interactions of the complexes 1 and 2 have been investigated by UV spectra, emission spectra and cyclic voltammogram. Concluding the results of three methods used to measure the interaction of complexes 1 and 2 with DNA, the action mode of the two complexes with DNA is intercalation, and character of ligands and steric effect may affect the interaction of the complexes with DNA.