The Experts below are selected from a list of 3315 Experts worldwide ranked by ideXlab platform
Julian R. Levell - One of the best experts on this subject based on the ideXlab platform.
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Molecular Engineering of Benzo[b]Pyrylium Salts by Indirect Electrophilic Substitution
European Journal of Organic Chemistry, 1998Co-Authors: Alan Roy Katritzky, Peter Dr. Czerney, Julian R. Levell, Weihong DuAbstract:Benzotriazole-mediated indirect electrophilic substitution in the position para to the oxygen atom of benzo[b]Pyrylium salts has been used for the synthesis of long-chain and bifunctional benzo[b]Pyrylium species. The methodology has potential for application in high technology and the pharmaceutical industries, for the molecular engineering of new functionalized derivatives.
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Benzotriazole-Mediated Conversions of para-H-Substituted Pyrylium, Benzo[b]Pyrylium, and Xanthylium Salts into para-Position Functionalized Derivatives (An Indirect Electrophilic Substitution of Electron-Deficient Heteroaromatics).
The Journal of organic chemistry, 1997Co-Authors: Alan R. Katritzky, Peter Dr. Czerney, Julian R. LevellAbstract:4H-Substituted Pyrylium 9, benzo[b]Pyrylium 15, and xanthylium salts 22 react with benzotriazole to give the corresponding 4H-(benzotriazol-1-yl)pyrans 10, benzo[b]pyrans 16, or xanthenes 23. Novel...
Igor Dubey - One of the best experts on this subject based on the ideXlab platform.
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interaction of cyanine dyes with nucleic acids part 19 new method for the covalent labeling of oligonucleotides with Pyrylium cyanine dyes
Bioorganic & Medicinal Chemistry Letters, 2000Co-Authors: S M Yarmoluk, Alexander M Kostenko, Igor DubeyAbstract:New chemistry for the fluorescent labeling of oligonucleotides with cyanine dyes is proposed. It is based on the use of Pyrylium salts as amine-specific reagents. Monomethyne Pyrylium cyanine dye 1 was covalently linked to 5'-aminoalkyl modified oligonucleotide, with simultaneous conversion of the non-fluorescent dye 1 into fluorescent pyridinium cyanine structure 2.
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interaction of cyanine dyes with nucleic acids 4 efficient 5 fluorescent labelling of oligonucleotides with monomethyne Pyrylium cyanine dye cyan 39
Biopolymers & Cell, 1998Co-Authors: S M Yarmoluk, Alexander M Kostenko, Olga S Kornushyna, Igor DubeyAbstract:A new system for fluorescent 5'-end labelling of oligonucleoti des with cyanine dyes is proposed. Reaction of primary amine with Pyrylium salt was used for the efficient conjugation of monomethyne Pyrylium cyanine dye with 5'-aminoalkyl oligonucleotide with simultaneous conversion of the «brightless» Pyrylium dye Cyan 39 into «bright» pyridinium one Cyan 40.
Sergiy M. Yarmoluk - One of the best experts on this subject based on the ideXlab platform.
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New Approach for Fluorescent Peptide Labeling with Pyrylium Cyanine Dyes
Journal of Fluorescence, 2002Co-Authors: O. M. Kostenko, S. Y. Dmitrieva, O. I. Tolmachev, Sergiy M. YarmolukAbstract:New approach for fluorescent peptide labeling with cyanine dyes utilizing the reaction of Pyrylium salts with aliphatic aminogroup is proposed. The reaction of two Pyrylium cyanines dye acids was investigated. Lysocyme was used as a model peptide for conjugation. The proposed method can be used as a simple and convenient alternative for the known procedures because it does not require preparation of the unstable amino-reactive intermediates from a carboxyl- or sulfo-derivative of cyanine dyes.
John A. Mikroyannidis - One of the best experts on this subject based on the ideXlab platform.
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Substituent Effect on the Photobleaching of Pyrylium Salts under Ultrashort Pulsed Illumination
The journal of physical chemistry. B, 2006Co-Authors: I. Polyzos, Mihalis Fakis, Vassilis Giannetas, Peter Persephonis, George Tsigaridas, John A. MikroyannidisAbstract:The current article presents the photobleaching properties of a group of Pyrylium salts under ultrashort pulsed illumination. These Pyrylium salts have the same basic chemical structure and differ only by a specific substituent. It is proven experimentally that two different mechanisms are simultaneously present to the photobleaching of all molecules studied (independently of their specific chemical structure). However, the particular parameters of each mechanism are influenced significantly by the substituent change. The experimental investigation of these parameters showed the presence of multiphoton interactions in the photobleaching of Pyrylium salts depending essentially on the specific substituent.
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Novel class of Pyrylium dyes with high efficiency in lasing and two-photon absorption fluorescence
Chemical Physics Letters, 2000Co-Authors: Mihalis Fakis, J Polyzos, G. Tsigaridas, John Parthenios, A. Fragos, Vassilis Giannetas, Peter Persephonis, John A. MikroyannidisAbstract:Abstract We report the synthesis of a promising class of Pyrylium dyes concerning laser and two-photon absorption action. Three representatives of this class, 4-(2,4-dichlorophenyl)-2,6-bisphenylPyrylium tetrafluoroborate, 4-phenyl-2,6-bis(4-methoxyphenyl)Pyrylium tetrafluoroborate, and 4-(2,4-dichlorophenyl)-2,6-bis(4-biphenyl)Pyrylium tetrafluoroborate, were investigated. Each dye was synthesized by a convenient and inexpensive method. Efficient laser action was shown at ∼500, ∼560, ∼615 nm. Changing the conjugation length i.e. the length of the oligophenyl moiety, or introducing various substituents on the aromatic rings, the emission maximum can be controlled. Two-photon absorption induced fluorescence was also observed. These Pyrylium dyes constitute excellent candidates for laser technology and two-photon absorption applications.
S M Yarmoluk - One of the best experts on this subject based on the ideXlab platform.
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interaction of cyanine dyes with nucleic acids part 19 new method for the covalent labeling of oligonucleotides with Pyrylium cyanine dyes
Bioorganic & Medicinal Chemistry Letters, 2000Co-Authors: S M Yarmoluk, Alexander M Kostenko, Igor DubeyAbstract:New chemistry for the fluorescent labeling of oligonucleotides with cyanine dyes is proposed. It is based on the use of Pyrylium salts as amine-specific reagents. Monomethyne Pyrylium cyanine dye 1 was covalently linked to 5'-aminoalkyl modified oligonucleotide, with simultaneous conversion of the non-fluorescent dye 1 into fluorescent pyridinium cyanine structure 2.
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interaction of cyanine dyes with nucleic acids 4 efficient 5 fluorescent labelling of oligonucleotides with monomethyne Pyrylium cyanine dye cyan 39
Biopolymers & Cell, 1998Co-Authors: S M Yarmoluk, Alexander M Kostenko, Olga S Kornushyna, Igor DubeyAbstract:A new system for fluorescent 5'-end labelling of oligonucleoti des with cyanine dyes is proposed. Reaction of primary amine with Pyrylium salt was used for the efficient conjugation of monomethyne Pyrylium cyanine dye with 5'-aminoalkyl oligonucleotide with simultaneous conversion of the «brightless» Pyrylium dye Cyan 39 into «bright» pyridinium one Cyan 40.
