title: Iminocoumarin-based low affinity fluorescent Ca2+ indicators excited with visible light.
abstract: A series of iminocoumarin-based fluorescent Ca2+ indicators were synthesized and the spectral profiles of their free and Ca2+ bound forms were studied. The newly-synthesized compounds incorporate the Ca2+ chelating structure of BAPTA. The chromophore moieties are iminocoumarins substituted at the 3-position with benzothiazolyl, benzoxazolyl and benzimidazolyl groups. These compounds are excited with visible light and their Ca2+ dissociation constants range from 5.4 to 27.5 microM. Fluorescence spectra studies of these probes indicated a clear shift in their excitation wavelength maxima upon Ca2+ binding along with changes in fluorescence intensity that enable the compounds to be used as low Ca2+ affinity, visible excitable probes.
authors.affiliation: Department of Chemistry, University of Crete, Heraklion, 71409, Greece.
authors.forename: F
authors.initials: F
authors.lastname: Liepouri
authors.forename: E
authors.initials: E
authors.lastname: Foukaraki
authors.forename: T G
authors.initials: TG
authors.lastname: Deligeorgiev
authors.forename: H E
authors.initials: HE
authors.lastname: Katerinopoulos
mesh_terms: D002118:Calcium / Q000032:analysis*; D002614:Chelating Agents / Q000737:chemistry; D003374:Coumarins / Q000138:chemical synthesis / Q000528:radiation effects*; D004533:Egtazic Acid / Q000031:analogs & derivatives* / Q000737:chemistry; D005456:Fluorescent Dyes / Q000138:chemical synthesis / Q000528:radiation effects*; D008027:Light; D015394:Molecular Structure
chemical_list: D002614:Chelating Agents; D003374:Coumarins; D005456:Fluorescent Dyes; D004533:Egtazic Acid; C030123:coumarin; C025603:1,2-bis(2-aminophenoxy)ethane-N,N,N',N'-tetraacetic acid; D002118:Calcium