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A novel cadmium complex with mixed ligands {[Cd(2,2'-biim)(4,4'-bipy)(H 2 O)(ClO 4 )] (ClO 4 )} n ( 1 ) (2,2'-biim = 2,2'-biimidazole; 4,4'-bipy = 4,4'-bipyridine) has been synthesized through hydrothermal reaction and its crystal structure was determined by single-crystal X-ray diffraction technique. Single-crystal X-ray diffraction analyses revealed that complex 1 crystallizes in the space group Pna 2 1 of the orthorhombic system and exhibits a one-dimensional zigzag chain structure consisting of [Cd(2,2'-biim)(4,4'-bipy)(H 2 O)(ClO 4 )] n n + cationic chains and isolated ClO 4 – anions. Powder photoluminescent characterization reveals that complex 1 has an emission in the green region of the spectrum. Time-dependent density functional theory (TDDFT) calculation showed that the nature of the photoluminescence of complex 1 is originated from the ligand-to-ligand charge transfer (LLCT; from the HOMO of the perchlorate anions to the LUMO of the 4,4'-bipy ligand). A wide optical band gap of 3.25 eV was found by the solid-state UV/vis diffuse reflectance spectrum.

A novel ligand, diethylenetriamine-N,N′,N″-tri(acetyl-p-hydroxybenzoyl hydrazine)-N,N″-bisacetic acid, and its three soluble non-ion transition metal complexes, ML· nH2O (M = Mn, n = 4; M = Co, Ni,...

A novel ligand, diethylenetriamine-N,N″-bis(acetyl-m-hydroxybenzoyl hydrazine)-N, N′, N″-triacetic acid (H3L), was synthesized and characterized on the basis of elemental analysis, molar conductivities, 1H NMR, FAB-MS, TG-DTA analysis, and IR methods. Its complex of Gd(III) holding promise of magnetic resonance imaging(MRI) was synthesized, and relaxivity of GdL and Gd(DTPA)2– used as compare were determined in water solution, respectively. The relaxivity of GdL (R1 = 6.02 L·mmol–1·s–1) was larger than that of Gd(DTPA)2–(R1 = 4.34L·mmol–1·s–1). The relaxivity of GdL had also been investigated in human serum albumin (HSA) solution, the relaxivity of GdL was enhanced from 6.02 L·mmol–1·s–1 in water solution to 7.10 L·mmol–1·s–1 in HSA solution. In addition, thermodynamics stability constant of GdL complex was determined. The results showed that GdL is a prospective MRI contrast agent, although the thermodynamic stability constant of GdL complex(K GdL = 1019.92) was a little less than that of Gd(DTPA)2–(KGd-...

A novel ligand (H3L), diethylenetriamine-N,N″-bis(acetyl-o-hydroxybenzoyl hydrazide)-N, N′, N″-triacetic acid and its four rare earth (La, Eu, Gd, Tb) complexes have been synthesized and characterized on the basis of elemental analyses, molar conductivities, 1H NMR spectra, FAB-MS, TG-DTA analysis, and IR spectra. In addition, relaxivity (R1) of complexes are determined. The relaxivity of LaL, EuL, GdL, TbL, and Gd(DTPA)2– used as a control are 0.94, 2.79, 6.39, 1.59, and 4.34 L·mmol−1·s−1, respectively. The spin-lattice relaxivity of GdL is larger than that of Gd(DTPA)2−. The results showed that complex of GdL may be a potential magnetic resonance imaging contrast agent.

In this paper, two novel ligands (H3L1, H2L2) have been synthesized from diethylene triamine pentaacetic acid (DTPA) and isoniazid in different conditions. H3L1 has three carboxylic groups, and H2L2 has two carboxylic groups. Their non-ion complexes of GdL1 and MnL2 holding promise of magnetic resonance imaging (MRI) are synthesized, and relaxivity of complexes are determined, respectively. The relaxivity of GdL1 (R1 = 6.07 L·mmol−1·s−1) and MnL2 (R1 = 6.94 L·mmol−1·s−1) are larger than that of Gd(DTPA)2− (R1 = 4.34 L·mmol− 1·s−1). It is more significative that relaxivity of MnL2 is larger than that of GdL1. The results showed that two non-ion complexes are prospective MRI contrast agents.

A novel ligand (H2L), diethylenetriamine-N,N′,N′′-triacetylisoniazide N,N′′-bisacetic acid, and its four non-ion transition metal complexes, ML · nH2O (M = Mn, n = 4; M = Co, Ni, n = 2; M = Cu, n = 1), have been synthesized and characterized on the basis of elemental analysis, molar conductivity, 1H-NMR, FAB-MS, TG-DTA analysis and IR spectrum. In addition, relaxivity (R1) of the complexes was determined, the relaxivity of MnL, CoL, NiL, CuL as well as Gd(DTPA)2− used as a control are 6.94, 2.79, 2.52, 1.59 and 4.34 l mmol−1 s−1, respectively. The relaxivity of MnL is larger than that of Gd(DTPA)2−. The results show that the complex of MnL may be a potential MRI contrast agent.