Coumarin-labeled thioesters are efficiently prepared from biological
thiols using N-coumarin-3-carbonyl benzotriazoles. Absorption
(λabs), fluorescence (λem)
wavelength maxima and quantum yields (φ) for the thioesters are measured in buffer solution at physiological
pH 7.4. Quantum yields (φ = 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 (φ = 0.0195), suggesting that derivatives
of this type could be suitable for quantitative thiol assays.
fluorescence - acylation - coumarin - thiols - benzotriazoles - peptides - amino acids
- heterocycles