Synthesis of new chiral fluorescent sensors and their applications in enantioselective discrimination

Synthesis of novel fluorescence probes and their application in the enantioselective recognition of arginine

Arginine (Arg) plays a crucial and multifaceted role in various biological processes, encompassing cell division, wound healing, immune system modulation, and plant signaling. This study introduced a pair of novel chiral fluorescent probes, (R)-5 and (S)-5, constructed upon the BINOL framework, which exhibited enantiomeric selectivity and sensitivity to d-Arg/l-Arg in fluorescence experiments. These probes offered a simple, rapid, low-cost, and highly selective method for detecting Arg enantiomers, thereby providing a highly sensitive approach for their qualitative and quantitative analysis. The enantioselective fluorescence enhancement ratios {ef = [(I1 - I0)/(I2 - I0) = ΔI1/ΔI2]} of (R)-5 and (S)-5 to Arg were 1694 and 5163, respectively. Moreover, the probes demonstrated the capability to detect the concentration of d-Arg and l-Arg with a limit of detection of 4.84 × 10-7 M and 3.35 × 10-7 M, respectively, as well as determine the enantiomeric excess. These probes exhibited high chemical selectivity and enantioselectivity, enabling the identification of different configurations of Arg, quantification of Arg concentrations, and determination of the enantiomeric composition of Arg. This study provides valuable insights for the development of sensitive and selective chiral molecular detection methods, significantly advancing our comprehension of the relationship between Arg concentration and probe fluorescence response.

Effective enantioselective recognition by steady-state fluorescence spectroscopy: Towards a paradigm shift to optical sensors with unusual chemical architecture

A series of amino acid-derived 1,2,3-triazoles presenting the amino acid residue and the benzazole fluorophore connected by a triazole-4-carboxylate spacer was studied for enantioselective recognition using only steady-state fluorescence spectroscopy in solution. In this investigation, the optical sensing was performed with D-(-) and L-(+)-Arabinose and (R)-(-) and (S)-(+)-Mandelic acid as chiral analytes. The optical sensors showed specific interactions with each pair of enantiomers, allowing photophysical responses, which were used for their enantioselective recognition. DFT calculations confirm the specific interaction between the fluorophores and the analytes corroborating the observed high enantioselectivity of these compounds with the studied enantiomers. Finally, this study investigated nontrivial sensors for chiral molecules by a mechanism different than turn-on fluorescence and has the potential to broad chiral compounds with fluorophoric units as optical sensors for enantioselective sensing.

Synthesis of novel chiral fluorescent sensors and their application in enantioselective discrimination of chiral carboxylic acids

Novel chiral fluorescent sensors are synthesized from a dibromide containing a tetraphenylethylene moiety and enantiomerically pure amino alcohols and an amine. The sensors are applied for the chiral recognition of a wide range of chiral carboxylic acids and related derivatives.

A photo-stable fluorescent chiral thiourea probe for enantioselective discrimination of chiral guests

Herein, a chiral thiourea Schiff base derived from (1R,2R)-1,2-cyclohexanediamine and tetraphenylethylene (TPE) was applied as a highly effective chiral sensor for the enantioselective discrimination of various acids and aminesviaion-pair and hydrogen-bond interaction.