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Three new aryl amide type ligands, N-(phenyl)-2-(quinolin-8-yloxy)acetamide (L(1)), N-(benzyl)-2-(quinolin-8-yloxy)acetamide (L(2)) and N-(naphthalene-1-yl)-2-(quinolin-8-yloxy)acetamide (L(3)) were synthesized. With these ligands, three series of lanthanide(III) complexes were prepared: [Ln(L(1))(2)(NO(3))(2)]NO(3), [Ln(L(2))(2)(NO(3))(2)(H(2)O)(2)]NO(3).H(2)O and [Ln(L(3))(2)(NO(3))(2)(H(2)O)(2)]NO(3).H(2)O (Ln=La, Sm, Eu, Gd). The complexes were characterized by the elemental analyses, molar conductivity, (1)H NMR spectra, IR spectra and TG-DTA. The fluorescence properties of complexes in the solid state and the triplet state energies of the ligands were studied in detail, respectively. It was found that the Eu(III) complexes have bright red fluorescence in solid state. The energies of excited triplet state for the three ligands are 20325 cm(-1) (L(3)), 21053 cm(-1) (L(2)) and 22831 cm(-1) (L(1)), respectively. All the three ligands sensitize Eu(III) strongly and the order of the emission intensity for the Eu(III) complexes with the three ligands is L(3)L(2)L(1). It can be explained by the relative energy gap between the lowest triplet energy level of the ligand (T) and (5)D(1) of Eu(III). This means that the triplet energy level of the ligand is the chief factor, which dominates Eu(III) complexes luminescence.

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.

A novel ligand, diethylenetriamine-N,N''-bis(acetyl-isoniazid)-N,N',N''-triacetic acid (H(3)L) has been synthesized from diethylene triamine pentaacetic acid (DTPA) and isoniazid. Ligand and its five neutral rare earth (RE=La, Sm, Eu, Gd, Tb) complexes holding promise of magnetic resonance imaging (MRI) were characterized on the basis of elemental analysis, molar conductivity, (1)H-NMR spectrum, FAB-MS, TG-DTA analysis and IR spectrum. The relaxivity (R(1)) of complexes and Gd(DTPA)(2-) used as a control were determined. The relaxivity of LaL, SmL, EuL, GdL, TbL and Gd(DTPA)(2-) were 0.14, 1.66, 3.14, 6.08, 2.79 and 4.34 l.mmol(-1).s(-1), respectively. The spin-lattice relaxivity of GdL was larger than that of Gd(DTPA)(2-). The relaxivity of GdL had also been investigated in human serum albumin (HSA) solution, the relaxivity of GdL was enhanced from 6.08 l.mmol(-1).s(-1) in water solution to 9.09 l.mmol(-1).s(-1) in HSA solution. In addition, thermodynamics stability constant of GdL complex was determined, the thermodynamic stability constant of GdL complex (K(GdL)=10(20.84)) was a few larger than that of Gd(DTPA)(2-) (K(Gd-DTPA)=10(20.73)). The results showed that complex of GdL may be a prospective MRI contrast agent with low osmotic pressure due to non-ion complex, high spin-lattice relaxivity, good stability and binding affinity for the serum protein.

The reaction of the bicyclic anhydride of diethylenetraiamine-pentaacetic acid (DTPAA) with inositol gave diethylenetriamine-inositol-biester- N , N ′ , N ″-triacetic acid (DTPA-BI) ( 1 ). ( 1 ) was characterized by FAB-MS, 1 HNMR, IR and elemental analysis. Its chelates of Gd(III), Fe(III) and Mn(II) holding promise of magnetic resonance imaging (MRI) were synthesized. Gd(III) complex was obtained from Gd 2 O 3 and the acid form of ( 1 ). Thermodynamic stability constant and relaxation of Gd(III) complex with DTPA-BI were determined. The spin–lattice relaxivity ( R 1 =5.6 l mmol −1 s −1 ) of chelate was slightly larger than that of [GdDTPA] 2− . The results showed that the complex is a prospective MRI agent, although thermodynamic stability constant of DTPA-BI K [GdDTPA-BI] − =10 18.2 was a little less than that of [GdDTPA] 2− (K [GdDTPA] 2− =10 20.73 ).

A thiosemicarbazone derivative of the Vitamin K3 has been synthesized. Five transition metal complexes of the thiosemicarbazone have been prepared and characterized by i.r., u.v.–vis., molar conductance and thermal analyses. All of the complexes possess strong inhibitory action against G(+) Staphylococcus aureus, G(−) Hay bacillus, and G(−) Eschericha coli. The antibacterial activities of the complexes are stronger than those of the thiosemicarbazone itself.

A novel ligand, diethylenetriamine-N,N''-bis(acetyl-p-hydroxybenzoyl hydrazine)-N,N',N''-triacetic acid (H3L) was synthesized and characterized on the basis of elemental analysis, molar conductivity, 1H-NMR spectrum, FAB-MS, TG-DTA analysis and IR spectrum. Its complex of Gd(III) holding promise of magnetic resonance imaging (MRI) was synthesized, and relaxivity (R1) of complex and Gd(DTPA)2- used as a control was determined in water solution, respectively. The relaxivity of GdL (R1 = 6.39 l.mmol(-1).s(-1)) was larger than that of Gd(DTPA)2- (R1 = 4.34 l.mmol(-1).s(-1)). The relaxivity of GdL has also been investigated in human serum albumin (HSA) solution, the relaxivity of GdL was enhanced from 6.39 l.mmol(-1).s(-1) in water solution to 7.69 l.mmol(-1).s(-1) in HSA solution. In addition, thermodynamics stability constant of GdL was determined. The results showed that complex of GdL is a prospective MRI contrast agent, although the thermodynamic stability constant of GdL complex (K(GdL) = 10(19.56)) was a little less than that of Gd(DTPA)2- (K(Gd-DTPA) = 10(20.73)).

Four rare earth complexes with alizarin yellow R have been prepared and characterized by elemental analysis, IR, UV and 1H NMR in this paper. Their general formula was determined as the following: Na[REL2] x 2H2O (RE = Sm, Eu, Tb, Y. NaHL = alizarin yellow R). The IR shows that the phenolic proton dissociates and the phenolic oxygen atom is coordinated to metals. The carboxylic oxygen atom is coordinated to metals by single dentate. The phenolic oxygen atom together with carboxylic oxygen atom chelates with ion forming a six-mumber ring. Two water molecules are coordinated to rare earth ion. The spectrum of the ligand shows that a band at 398 nm is shifted to 351-355 nm in the complexes showing that the carbonyl oxygen and phenolic oxygen atom are coordinated to the metal ion. The oxygen atom of group -NOq and nitrogen atom of -N = N- do not bind to metal ions. The strong red fluorescence of Eu (III) complexes is observed in the light of fluorescence lamp. Two strong fluorescence peaks of complex Na [EuL2] x 2H2O may be attributed to the fluorescence spectra of (5)D0 --(7)F1 and (5)D0 --7F2 transitions of Eu3+.

A series of esters and amides of diethylenetriamine-penta-acetic acid have been synthesized from diethylene triamine penta acetic acid (DTPA) with an efficient and mild synthesis method. All these compounds obtained were characterized by Fab-MS, 1H NMR, IR, and elemental analysis.

A series of aza-crown ethers were synthesised by the in situ reduction of Schiff base crown ethers that were obtained by the condensation of a dialdehyde with a diamine in methanol solution. The aza-crown ethers were characterised by elemental analysis, FAB-MS, IR, and 1H NMR. They were obtained in good yields.