α-Aminoxy acid conjugates and hybrid α-aminoxy dipeptide conjugates showing blue to green fluorescence (with quantum yields 0.23-0.71) were synthesized (75-92% yield) from N-acylbenzotriazoles. 7-Methoxycoumarin derivatives were obtained (quantum yields φ 0.35-0.71) that could be suitable for peptide assays. The wavelengths of the absorption maxima (λAbs) and the fluorescence emission maxima (λEm)
Photophysics of novel coumarin-labeled depsipeptides in solution: sensing interactions with SDS micelle via TICT model
作者:Suvendu Biswas、Ilker Avan、Akash K. Basak、Nader E. Abo-Dya、Abdullah Asiri、Alan R. Katritzky
DOI:10.1007/s00726-013-1483-3
日期:2013.7
N-Acylbenzotriazoles enable the synthesis (69-92 % yield) of blue to green fluorescent coumarin-labeled depsidipeptides 8a-f (quantum yields 0.004-0.97) and depsitripeptides 12a-d (quantum yields 0.02-0.96). Detailed photophysical studies of fluorescent coumarin-labeled depsipeptides 8a-f and 12a-d are reported for both polar protic and polar aprotic solvents. 7-Methoxy and 7-diethylaminocoumarin-3-ylcarbonyl depsipeptides 8c,f and 12d are highly solvent sensitive. These highly fluorescent compounds could be useful for peptide assays. Further photophysical studies of 7-diethylaminocoumarin-labeled depsipeptides 8c,12d within the micellar microenvironment of SDS reflect their ability to bind with the biological membrane, suggesting potential applications in the fields of bio- and medicinal chemistry.
Synthesis of Coumarin Conjugates of Biological Thiols for Fluorescent Detection and Estimation
Coumarin-labeled thioesters are efficiently prepared from biological thiols using N-coumarin-3-carbonyl benzotriazoles. Absorption (λabs), fluorescence (λem) wavelength maxima and quantum yields (Ï) for the thioesters are measured in buffer solution at physiological pH 7.4. Quantum yields (Ï = 0.0318-0.1068) of four of the products are higher than their precursor 7-methoxy-3-(1H-benzotriazol-1-ylcarbonyl)-2H-chromen-2-one (Ï = 0.0195), suggesting that derivatives of this type could be suitable for quantitative thiol assays.