Bis Acetic Acid Research Articles

Synthesis Soluble Non-Ion Transition Metal Manganese(II), Cobalt(II), Nickel(II) Complexes of Diethylenetriamine-N,N′,N″-tri(acetyl-p-hydroxybenzoyl hydrazine)- N,N″- Bisacetic Acid as Potential Contrast Enhancement Agent

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, n = 2) have been synthesized and characterized on the basis of elemental analysis, molar conductivities, 1H NMR, FAB-MS, TG-DTA analysis, and IR methods. In addition, relaxivity of complexes are determined, The relaxivity (R1) of MnL, CoL, NiL, and Gd(DTPA)2– used as control are 6.33, 2.71, 2.60, and 4.34L·mmol−1·s−1, respectively. The spin-lattice relaxivity of MnL are larger than that of Gd(DTPA)2−. The results showed that complex of MnL may be a potential MRI contrast agent with high spin-lattice relaxivity, good solubility, low osmotic pressure due to non-ion complex.

Design and Synthesis of a New Class of Twin-Chain Amphiphiles for Self-Assembled Monolayer-based Electrochemical Biosensor Applications.

A new class of twin-chain hydroxyalkylthiols (mercaptoalkanols) featuring a nearly constant cross-section and the potential for modification of one or both termini are available with complete regioselectivity through Pd-mediated couplings of benzene diiododitriflate, including an example of a previously unreported coupling to generate an ortho-substituted arene bis acetic acid. Self-assembled monolayers (SAMs) prepared from the new amphiphiles demonstrate improved stability in an electrochemical sensor system compared with monolayers prepared from analogous single chain thiols.

Syntheses, crystal structures, and bond valence sum analyses of lanthanide complexes with a planar pentadentate ligand

The syntheses and X-ray crystal structures of the Eu, Gd, Dy, Ho, and Er nitrate complexes of the pentadentate ligand 2,6-diacetylpyridine bis acetic acid hydrazone, or H 2dapaah, are reported. The complexes can be divided into 3 groups depending on the number of water molecules per metal ion. The Ln · 4H 2O complexes with Eu, Gd and Dy are isomorphous, with the Ln ion being 10 coordinate. The Ln · 6H 2O group includes Ho and Er, where the cation is 9 coordinate. The final complex Gd · 5H 2O is 10 coordinate like the Eu, Gd and Dy complexes, but the additional water molecule has stabilized an ordered crystal. The bond valence sum method has been used to analyze the bonding in the complexes and has suggested that bond valence equalization in three dimensions may be an important concept.

Synthesis, Characterization and Relaxation Properties of Four Non-ion Transition Metal Manganese(II), Cobalt(II), Nickel(II) and Copper (II) Complexes with Derivatives from Diethylene Triamine Pentaacetic Acid and Isoniazid

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.

Synthesis and Properties of Two New Membrane-Impermeant High-Molecular-Weight Carbonic Anhydrase Inhibitors

The synthesis and inhibitory properties and stability of two nontoxic high-molecular-weight carbonic anhydrase inhibitors (F 3500 and POBUMS) are reported. F 3500 was prepared by the covalent linkage of aminobenzolamide, a potent carbonic anhydrase (CA) inhibitor, to polyoxyethylene bisacetic acid (MW 3350). Linkage of the same inhibitor to polybutadiene maleic acid copolymer (MW 20,000) gave POBUMS. They contained on a mole percentage basis 0.11–0.28% unreacted aminobenzolamide as contaminant. F 3500 and POBUMS were approximately equipotent as carbonic anhydrase inhibitors on a weight basis withKiat 37°C for CA II and CA IV of approximately 0.5 and 10 μg/ml, respectively. They showed a maximum release of 28% aminobenzolamide when heated at 70°C for 3 days at pH 10.5 and were completely stable toward enzymatic hydrolysis (protease and peptidase at 25°C). They were not membrane permeable as judged by their inability to bind to intracellular CA II in intact red cells, nor were they actively uptaken in rat kidney slices. Rats injected with F 3500 (200 mg/kg) showed no toxicity and excreted 93% of the polymer unchanged in the urine in 3 h. The two polymers should prove useful forin vivoandin vitrostudies of selective CA IV inhibition in membranes.

Formation constants of some mercury(II) complexes determined from their anodic polarographic signals

The formation constants of some Hg(II) complexes have been determined from the anodic polarographic signals for the oxidation of mercury in the presence of the following ligands: thiourea and its phenyl- and diphenyl-derivatives, thiocyanate, ethylenediamine, EDTA, methylthioacetic acid, 2,2'-thiobisacetic acid, 3,3'-thiobispropanoic acid, 2,2'-[1,1-methandiylbis(thio)]bisacetic acid and 2,2'-[1,2-ethandiylbis(thio)]bisacetic acid. The use of differential pulse polarography and a.c. polarography instead of d.c. polarography increases the accuracy and precision of the potential measurements and, as a consequence, of the stability constants determined. The results obtained by the different methods are compared.