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Information × Registration Number 0309U007013, 0107U000662 , R & D reports Title Organic polyheterocyclic luminescent compounds for biologically oriented analysis popup.stage_title Синтез і спектральні властивості флуоресценитних зондів із ефектом внутрішньомолекулярного переносу протона та ероносу заряду Head Dorochenko Andrii, Registration Date 21-01-2009 Organization Kharkov Natuional university named after V.N.Karazin popup.description2 Objects of investigation - the synthetic nitrogen- and oxygen-containing heterocyclic dyes, which are able to chemical transformations into luminescent species of different nature in their excited states. Uniting the structural fragments of 2,5-diphenyloxazole and 1,3,5-triphenyl-2-pyrazoline with 3-hydroxychromone system leads to the formation of fluorophores with the highest fluorescence efficiency among 3-hydroxychromones with anomalous spectral parameters determined by the excited state proton phototransfer reaction. The diphenyloxazolic 3-hydroxychromones were shown to belong to the family of compounds with the unusual to 3-hydroxychromones reversal electron density moving - from the pyronic cycle to the extended conjugated system moiety in position 2. The possibility of the alternative direction of proton phototransfer were demonstrated for the first time on the example of the quinolynic analog of 3-hydroxychromone, in which molecule the heterocyclic nitrogen atom plays the role of proton accepting center on the contrary to traditional to 3-hydroxychromones carbonyl group oxygen atom. The initial formation of the intramolecular hydrogen bond of the OH…N type in the crystalline state and in solutions was shown to be the reason of such behavior. The high sensitivity of the spectral parameters of ortho'-carboxy-para"-dimethylamino substituted 2,5-diphenyloxazole to the water contents in the organic solvents was elucidated, this allows quantitative detection of water down to 0.06%. Significant fluorescence enhancement was detected for this compound in the biological media. Its binding to the BSA protein was studied showing the prospects of this molecule application in biologically oriented analysis. Owing to the high fluorescence quantum yields, high sensitivity of their ratiometric response to the media polarity, the synthesized compounds have all chances for their application as fluorescence probes for various physico-chemical and biological investigations. Product Description popup.authors popup.nrat_date 2020-04-02 Close