Suppression of activity of Candida Albicans proteinases by cobalt chloride

Influence of cobalt (II) chloride on the system of Candida albicans proteinase (SAP C. alb.) (both in solution and immobilized on a surface of nitrocellulose membranes) has been investigated. In solution cobalt chloride inactivated inducible but not constitute enzyme. In the heterogenous sytem proteolitical effect of the cobalt ion on inductible proteinase was also observed

Synthesis and Complexing Ability of Hyperbranched Polyester Polyols Containing Carboxylic Acid Fragments

© 2018, Pleiades Publishing, Ltd. New hyperbranched polyester polycarboxylic acids containing terminal propanoic and acrylic acid fragments have been synthesized. According to the IR spectral data, the complexation of polydentate hyperbranched polyester polycarboxylic acids with Co(II), Ni(II), and Cu(II) ions involves chelation and bidentate bridging coordination by the terminal carboxy groups. All Co(II), Ni(II), and Cu(II) complexes with the obtained polyester polypropanoic acids are characterized by octahedral geometry of the coordination entity (MO6). The Co(II), Ni(II), and Cu(II) complexes with polyester polyacrylic acids have tetrahedral configuration of the coordination entity (MO4)

The stability of metal complexes with 8-mercaptoquinoline and alkyl-substituted 8-mercaptoquinolines in dimethylformamide

The stoichiometry and stability constants of 8-mercaptoquinoline and alkyl-8-mercaptoquinoline complexes of Zn(II), Cd(II), Pb(II), Ni(II), Bi(III) and Ag(I) were determined potentiometrically in dimethylformamide. The stability of the 8-mercaptoquinolinates decreases in the order Ag(I) ≫ Bi(III) ≫ Ni(II) ≫ Pb(II) ≫ Cd(II) ≫ Zn(II). Metal 7-methyl-8-mercaptoquinolinates are the most stable. The presence of the alkyl group in the 2-position (which has a steric effect) lowers the strength of metal-ligand bonding. © 1984

Electrochemical properties of crown-containing N-(thio)phosphoryl(thio)ureas and their complexes with 3d transition metals

The electrochemical behavior of crown-containing N-(thio)phosphoryl(thio)ureas and their complexes with 3d transition metals was studied by dc voltammetry on a graphite electrode in acetone. Crown-containing N-(thio)phosphoryl(thio)ureas are not reduced but are oxidized on solid electrodes in the examined range of potentials; the electrons are transferred via the (thio)urea group. Electrooxidation of macrocyclic Co(II), Ni(II), and Cu(II) complexes probably occurs via formation of M(III) complex species. Electroreduction of these metal complexes involves stepwise electron transfer, with the oxidation state of the metal atom decreasing to 0, followed by dissociation of the electrochemical reaction products

Synthesis and spectral characteristics of 2,2-bis(hydroxymethyl)propionic acid derivatives as model compounds for the estimation of properties of modified hyperbranched polyesters polyols

© 2015 Pleiades Publishing, Ltd. New amino and carboxy derivatives of methyl 2,2-bis(hydroxymethyl)propionate have been synthesized as models of terminal fragments of hyperbranched polyester polyamines and polyesters polycarboxylic acids, and their spectral characteristics have been studied

Interaction of secreted aspartic proteinase Candida albicans with ZnCl2: Complex formation and catalytic activity

The aim of work is to estimate ion Zn(II) influence on catalytic activity of secreted aspartic proteinase Candida albicans (SAP2). System ZnCl2 - SAP2 showed complex formation. Composition of [ZnmSAP2n] complex was 1:1, the stability constant was 4.73±0.20. Affinity constants in system SAP2 - human serum albumin (HSA) - ZnCl2 were determined at Skatchard coordinates. The SAP2 was found to have a one section for linking with the substrate and one section for linking with modulator. The affinity constants in SAP2 - HSA system decreased in presence of ZnCl2. Complex forming of SAP2 - ZnCl2 system resulted in reduction of enzyme-substrate bonding. Proteolytic activity of SAP2 towards HSA at presence ZnCl2 as modulator was estimated. The inhibition effect in range 1×10-4 - 4×10-6 and 6×10-7 - 1×10-8 M was observed. The SAP2 activation effect catalyzed by ZnCl2 at 5×10-7 - 5×10-6 M concentrations were fixed for the first time. © IDOSI Publications, 2013

Synthesis and Properties of Water-Soluble Branched Polyester Poly{3-[3-(morpholin-4-yl)propyl]amino}propionate and Its Copper(II) Complex

© 2018, Pleiades Publishing, Ltd. A new water-soluble multidentate ligand based on a second-generation hyperbranched polyester containing 3-(morpholin-4-yl)propionate fragments in the terminal position has been synthesized, and its complex with copper(II) has been obtained. The degree of polyester functionalization with aminopropylmorpholine is 56%

Polynuclear copper(II) complexes with polydentate nanoligands on the basis of aminoderivatives of the hyperbranched polyesters

Coordinationally active polydentate nanoplatforms on the basis of amino-modified hyperbranched polyesters containing 7 terminal amino fragments are synthesized. Synthetic procedure is developed and polynuclear Cu(II) complexes with polyesteropolyamines are prepared. Their composition and stability of the complex forms in DMSO-water solutions are evaluated. It is found that all the compounds obtained exhibit biological activity with respect to the induced asparagine proteinase of Candida albicans. © Pleiades Publishing, Ltd., 2011

Inversion-voltammetric determination of heavy metal ions on electrodes modified with mono- and bis-N-thiophosphoryl thiourea

A method is proposed for determining Ni2+, Co2+, Cu2+, Cd2+, and Pb2+ ions by inversion voltammetry on carbon-paste electrodes modified with N- diisopropoxythiophosphoryl-N′-phenyl thiourea and its derivatives: N,N′-bis-(diisopropoxythiophosphorylamidothiocarbonyl)-1, 5-diamino-3-oxapentane, N,N′-bis- (diisopropoxythiophosphorylamidothiocarbonyl)-1,8-diamino-3,6-dioxaoctane and N,N′-bis-(diisopropoxythiophosphorylaminothiocarbonyl)-1, 10-diaza-18-crown-6

Synthesis of hyperbranched polyester polymaleic acids third generation

The third generation hyperbranched polyesterpolyol has been modified with maleic anhydride at various ratios of the polyol to the modifying agent, from 1: 6 to 1: 18. The prepared modified polyols are capable of the complex formation with copper(II), cobalt(II), and nickel(II) ions. © 2013 Pleiades Publishing, Ltd