Antimycobacterial activity of mixed-ligand copper quinolone complexes

New mixed-ligand Cu^II, complexes: [Cu(cf)(phen)Cl)](BF₄) · 4H₂O (3), [Cu(cf)(bipy)(Cl)](BF₄) · 2H₂O (4) and [Cu(cf)(dafone)(Cl)](BF₄) · 2H₂O (5) (cf = ciprofloxacin, phen = 1,10-phenanthroline, bipy = 2,2-bipyridine and dafone = 4,5-diazafluoren-9-one) have been isolated and characterized by elemental analyses, i.r., u.v.–vis. spectra, magnetic susceptibility and cyclic voltammetry. Complex (4) crystallizes in the monoclinic space group P2₁/n with a = 13.8919(13) Å, b = 14.5718(13) Å, c = 14.0725(13) Å, = 95.150(2)°, V=2837.2(5) ų. All complexes possess square-pyramidal geometry. The antimycobacterial activity of ciprofloxacin and complexes (3–5) has been evaluated against Mycobacterium smegmatis, which shows clear enhancement in the antitubercular activity upon copper complexation with N—N donors.     

Electrochemical studies of copper(II) 2-acetylpyridine4 N-dialkylthiosemicarbazones. Relation to their spectral,magnetic, and biological properties

Summary Quasireversible copper(II)/copper(I) couples are observed for [Cu(L)X], where X=Cl or Br, and L=an anion of a 2-acetylpyridine⁴ N-dialkylthiosemicarbazone. Irreversible reduction potentials of the tridentate (NNS) ligands increase as the size of the⁴ N-dialkyl-substituent increases. The growth inhibitory activity of the complex againstPaecilomyces variotii (but not other fungi tested) also decreases with increasing ligand size, suggesting that ease of ligand reduction is a significant factor in activity against this fungus.     

Alkaline phosphatase assay using a near-infrared fluorescent substrate merocyanine 700 phosphate

Alkaline phosphatase (ALP) is a phosphomonoester hydrolase that is commonly used as a conjugating enzyme in biological research. A wide variety of substrates have been developed to assay its activity. In this study, we developed an ALP assay method utilizing merocyanine 700 (MC700) based substrate MC700 phosphate (MC700p). MC700 is a near-infrared fluorescent merocyanine dye, and has excitation/emission maxima at 686 nm/722 nm in ALP assay buffer. Upon hydrolysis by ALP, MC700p is converted to MC700. The fluorescence of MC700 is dependent on the pH and detergent concentration in the buffer. The fluorescence signal produced by MC700p hydrolysis is linearly related to the ALP amount and substrate concentration. A stop solution containing EDTA could be used to stop the ALP/MC700p reaction. It was also demonstrated that MC700p could substitute pNpp as the ALP substrate in a commercial 17β-Estradiol enzyme immunoassay kit.