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Silver Ion Complexes with Macrocyclic Compounds Build on the Basis of Cyclotriphosphazene Ring

Seliger P., Andrijewski G., Siwy M., Sęk D.

Polish Journal of Chemistry

2009

Vol. 83, nr 4

581-588

The new diethanethiol-dipyrrolidinyl PNP-lar iat ether, L2, was syn the sized. Spectral properties of the tetrapyrrolidinyl PNP-lar iat ether L1 as well as L2 and their complexes with silver cat ion were investigated. The formation constants of the complexes with Ag+ in methanol solutions were determined. The 1H NMR and potentiometric measurements in dicate that in both cases complexation of Ag+ ions pro ceeds with participation of endocyclic nitrogen atom of cyclophosphazene ring and of polyether oxygen donors. In the case of L2 there is no evidence for stabilization of the ob tained complex by ethanethiol sub units attached to the exocyclic P atom. There is also no evidence for additional stabilization by cyclophosphazene ring or any of the pyrrolidinyl groups.

Synthesis, Characterization, DNA Binding and Cleavage Studies of Some Novel Biosensitive Transition Metal(II) Complexes

Raman R., Joseph J.

Polish Journal of Chemistry

2007

Vol. 81, nr 7

1303-1311

Four novel Knoevenagel type Cu(II), Ni(II), Co(II) and Zn(II) macrocyclic complexes derived from 3-cinnamalideneacetoacetanilide and N-(2-aminoethyl)-1,3-propanediamine have been synthesized. The nature of complexes and the geometry have been inferred from their microanalytical data, magnetic susceptibility measurements, IR, UV-Vis., 1H NMR, ESR and mass spectral techniques. The low electrical conductance of complexes supports their neutral nature.Monomeric nature of the complexes is assessed from theirmagnetic susceptibility values. The in vitro biological screening effects of the investigated compounds were tested against the bacteria E. coli, S. aureus, S. typhi and K. pneumoniae by the well diffusion method using agar nutrient as the medium. A comparative study of MIC values of the macrocyclic Schiff base ligand and its complexes indicates that the complexes exhibit higher antibacterial activity than the free ligand. The cyclic voltammetry method was used to probe the interaction of a Cu(II) complex with pUC18 DNA. Information of the binding ratio and intercalation mode can be obtained from its electrochemical data. Cyclic voltammetric measurements showed that Cu(II) complex undergoes a reversible reduction at biologically accessible potentials. From the study, it is understood that copper complex prefers to bind with DNAin Cu(II) rather than Cu(I) oxidation state. The DNAcleavage ability of the complexes was monitored by gel electrophoresis using super coiled pUC18 DNA in Tris-HCl buffer.

Synthesis and characterization of some new tin(IV) complexes with macrocyclic schiff bases

Singh H. L., Varshney A. K.

Bulletin of the Polish Academy of Sciences. Chemistry

2000

Vol. 48, No. 2

125-130

Some new tin (IV) complexes with macrocyclic Schiff bases, viz. 1,5,9,13-tetraaza-2,10-dimethyl-4,12-diphenyl cyclohexadeca-l,4,9,12-tetraene (L1) and 1,4,8,12-tetraaza-6,9,13,14-dibenzocyclotetradeca-l,4,8,11-tetraene (L2 ) have been synthesized. An attempt has been made to probe their structures on the basis of elemental analyses, molec-ular weight determination, electronic, infrared, 1H NMR and (119)Sn NMR spectroscopy. Molar conductance has shown the non-electrolytic behaviour of the tetravalent metal complexes that appear to be 1 : 1 electrolytes. Six-coordinate structure has been proposed for all tin complexes.