0000000000471752
AUTHOR
Gianluca Ambrosi
A Metal-Based Receptor for Selective Coordination and Fluorescent Sensing of Chloride
A scorpionate Zn2+ complex, constituted by a macrocyclic pyridinophane core attached to a pendant arm containing a fluorescent pyridyl-oxadiazole-phenyl unit (PyPD), has been shown to selectively recognize chloride anions, giving rise to changes in fluorescence emission that are clearly visible under a 365 nm UV lamp. This recognition event has been studied by means of absorption, fluorescence, and NMR spectroscopy, and it involves the intramolecular displacement of the PyPD unit by chloride anions. Moreover, since the chromophore is not removed from the system after the recognition event, the fluorescence can readily be restored by elimination of the bound chloride anion.
DNA binding and antiproliferative activity toward human carcinoma cells of copper(ii) and zinc(ii) complexes of a 2,5-diphenyl[1,3,4]oxadiazole derivative.
The interaction of calf thymus DNA with [CuL(ClO(4))]ClO(4)·H(2)O (1) and [ZnLBr]Br·H(2)O (2) (L = 9,12,15,18,27,28-hexaaza-29-oxatetracyclo[24.2.1.0(2,7).0(20,25)]enneicosa-2,4,6,20,22,24,26,28(1)-octaene) dicationic complexes in aqueous solution at neutral pH, was investigated by variable-temperature UV-vis absorption, circular dichroism and fluorescence spectroscopy. The values of the DNA-binding constants of these complexes, determined by competitive binding spectrofluorimetric titrations of ethidium bromide (EB)-DNA solutions, are (6.7 ± 0.5) × 10(6) M(-1) for CuL(2+) and (4.7 ± 0.5) × 10(5) M(-1) for ZnL(2+). These data together with a through analysis of the spectroscopic behaviour c…
Zn2+ and Cu2+ complexes of a fluorescent scorpiand-type oxadiazole azamacrocyclic ligand: crystal structures, solution studies and optical properties
A ligand comprised of a macrocyclic pyridinophane core having a pendant arm containing a secondary amine group linked through a methylene spacer to a pyridyl–oxadiazole–phenyl (PyPD) fluorescent system has been prepared (L). The crystal structures of [ZnL](ClO4)2 and [CuL](ClO4)2 show that M2+ is coordinated to all the nitrogen atoms of the macrocyclic core, the secondary amine of the pendant arm and the nitrogen atom of the pyridine group of the fluorescent moiety, the latter bond being clearly weaker than the one with the pyridine of the macrocycle. Solution studies showed the formation of a highly stable Cu2+ complex with 1 : 1 stoichiometry, whereas with Zn2+ least stable complexes were…
CCDC 1952561: Experimental Crystal Structure Determination
Related Article: Gianluca Ambrosi, M. Paz Clares, Isabel Pont, Mauro Formica, Vieri Fusi, Angela Ricci, Paola Paoli, Patrizia Rossi, Enrique García-España, Mario Inclán|2020|Dalton Trans.|49|1897|doi:10.1039/C9DT04764F
CCDC 1529591: Experimental Crystal Structure Determination
Related Article: Gianluca Ambrosi, M. Paz Clares, Isabel Pont, Mauro Formica, Vieri Fusi, Angela Ricci, Paola Paoli, Patrizia Rossi, Enrique García-España, Mario Inclán|2020|Dalton Trans.|49|1897|doi:10.1039/C9DT04764F