Dapoxyl

Fig. 17.5 Library of coumarin, Dapoxyl, styryl, hemicyanine, and rosamine scaffolds...

Dapoxyl Dye Library and Human Serum Protein Sensor... 

Dapoxyl dyes are highly environment-sensitive fluorescent compounds. Their fluorescence in water is very low, but induces a large change of fluorescence intensity, Stokes shifts, and extinction coefficients depending on pH and polarity of solvents. 

Fig. 17.8 (a) Synthetic scheme of a dapoxyl dye library (b) structure of hit compounds from dapoxyl library and excitation (left) and emission (right) spectra in different environments... 

Fig. 17.9 Solid-phase synthesis of a dapoxyl dye library (a) 2-chlorotrityl chloride resin, DIEA, THF (b) 10% piperidine, DMF (c) R2-C6H5-COOH, HATU, DIEA, CH2C12 (d) Ph3PCl2, TEA, CH2C12 (e) 1%TFA, CH2C12...

In conclusion, two combinatorial dapoxyl dye libraries were synthesized in both solution and solid phase methods and a fluorescence-based screening identified the highly sensitive and selective binding dye (A41-S) toward site I of HSA, demonstrating that this dapoxyl dye library has a great potential to sense macromolecules with fluorescence intensity changes. 

Reaction with functionalized coumarin dyes. Reaction with functionalized dapoxyl dyes. 

Environmentally-sensitive fluorescent structures are interesting scaffolds for probe development. On account of the high sensitivity of the dapoxyl core (2-pyridyl-5-aryl-... 

Figure 14.11. Solid-phase synthesis of dapoxyl dyes, (a) Library generation (b) fluorescence response of A41-S to increasing concentrations of HSA. Reproduced with permission from Ref. 52. Copyright 2007 American Chemical Society.

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