Bifunctional Diaminoterephthalate Scaffolds as Fluorescence Turn‐On Probes for Thiols

Abstract

The fluorescent diaminoterephthalate scaffold was equipped by amidation with three types of reactive functions: thiols for metal-surface binding, alkynes for click reactions, and maleimides for ligation with proteins. Starting from a succinyl succinate derivative with two orthogonally cleavable ester functions, three monoamides (38-57% yield over three steps) and two bisamides (19 and 25% yield over five steps) were prepared. Although alkyne and thiol derivatized compounds showed reasonable luminescence behavior (Φ≈1-4%), the fluorescence was quenched by the maleimide moiety. It was turned on (10- to 20-fold increase of fluorescence quantum yield) by conjugate addition of thiols.

Electron Transfer and Electron Excitation Processes in 2,5‐Diaminoterephthalate Derivatives with Broad Scope for Functionalization

“…Compounds 1 , 2 and 7 were prepared according to literature procedures. All other compounds were prepared specifically for this study according to Scheme (compounds 5 and 6 ) and Scheme (compounds 3 and 4 ).…”

“…DATs for biochemical applications have also been prepared as turn‐on probes, where the effect of higher fluorescence quantum yield was observed upon conjugated addition of benzylmercaptane . The DAT building block has been used for studying protein‐protein interactions, such as the dimerization of two molecules of recoverin .…”

Diaminoterephthalate Fluorescence Dyes – Versatile Tools for Life Sciences and Materials Science

“…Starting from the asymmetric benzyl‐methyl succinyl succinate 12 (see Scheme ), Freimuth et al have prepared maleimide and propargyl amide‐functionalized DAT 35 (Scheme ) . Again, a turn‐on effect of fluorescence is observed upon conjugated addition of BnSH by a factor of 10 (from Φ = 0.3 % in compound 35 to Φ = 3 % in product 36 ).…”

A Fast Dual-responsive OFF-ON Fluorescent Probe for Cysteine and Glutathione without Interference from Homocysteine

“…In recent years, fluorescent probes have attracted researchers' attention due to their feasibility in real application, high sensibility, and fast responding. Many published fluorescent probes works based on following mechanisms: condensation with cyanogroup, 5 nucleophilic substitution and rearrangement, 6,7 cyclization with aldehyde, [8][9][10] conjugate addition to maleimide, 11,12 and aromatic substitution rearrangement. [13][14][15] They all works well based on the reaction with sulfydryl/amino, but could not discriminate each other.…”