With the emerging interest in optical in vivo imaging, there is an increasing demand of photostable near-infrared (NIR) dyes. Herein we report the rational design of an amine tricarbocyanine structure with improved photostability (CyNA) and its combinatorial derivatization to render CyNA-414 as a NIR-fluorescent dye with stronger emission intensity and higher photostability than the NIR standar...

By condensation of quaternary benzothiazolium, quinolinium and acridinium salts having an active methyl group with 1-(3-bromopropyl)-4-chloroquinolinium or 1-(3-bromo-2-hydroxypropyl)-4-chloroquinolinium salts in the presence of a basic agent such as triethylamine, 8 asymmetric and symmetric monomethine cyanine dyes bearing !-bromopropyl substituent with one or two positive charges, were synthe...

Thin films of J-aggregate cyanine dyes deposited by layer-bylayer (LBL) assembly exhibit exciton-polariton dynamics when incorporated in an optical microcavity. Such LBL, J-aggregate thin films can be precisely deposited in a specific location in an optical microcavity, enabling the development of previously unachievable optoelectronic devices, as for example, the recently demonstrated resonant...

A clickable pyrrolopyrrole cyanine (PPCy) dye was synthesized by incorporating an alkyne moiety, followed by click reaction with azide-functionalized molecules of different polarities. The clickable dyes are readily amenable to labelling diverse molecules and exhibit an exceptionally high photostability and an impressive fluorescence quantum yield.

A convenient one-pot synthesis of chelating bis-N-heterocyclic carbene-ligated P(I) salts is described. The solid state structures of these remarkably stable phosphamethine cyanine dyes with various N-alkyl groups and counter-anions are reported, and initial reactivity results are discussed.

A series of new push-pull compounds were synthesised by reaction of 5-aryl- furan-2-carboxaldehydes and furo[b]pyrrole type aldehydes with benzothiazolium salts. These new condensation products represent highly conjugated systems that have potential biological activity. The reaction of furo[b]pyrrole type aldehydes with benzothiazolium salts give potential precursors of cyanine dyes.

Cyanine dyes are exceptionally useful probes for a range of fluorescence-based applications, but their photon output can be limited by trans-to-cis photoisomerization. We recently demonstrated that appending ring system to the pentamethine cyanine improves quantum yield and extends fluorescence lifetime. Here, we report an optimized synthesis persulfonated variants enable efficient labeling nuc...

The AM1ÈCI (Austin model 1 conÐguration interaction) method has been used to calculate energy gaps between the ground state and the lowest biradicaloid (BR) excited state as a measure for roughly (S 0) estimating the probability of reaching an conical intersection by bond twisting of one of the bonds S 0 ÈBR along the polymethine chain of unsymmetric cyanine dyes. Invoking qualitative concepts ...

The cyanine dyes Cy3 and Cy5 have proven valuable in numerous applications involving conjugation with proteins. Practical syntheses of lysine-selective, succinimidyl ester derivatives of these dyes have been published, and succinimidyl esters are commercially available. However, the published syntheses of cysteine-selective derivatives produce relatively low yields from expensive starting mater...

The solvent can exert significant in!-?uence on the pathways and rates of radiationless decay of the excited states of solute molecuIes. A major barrier to eIucidating such el3ects is the diversity of solute-solvent interactions which make it difficult to assign experimental observations to specific solvent properties. There exists, therefore, a great need for systematic experimental studies ai...