DEVELOPMENT OF A SPECTROPHOTOMETRIC METHOD FOR ASSESSMENT OF THE RELATIVE REACTIVITY OF MONOCARBONYL ANALOGS OF CURCUMIN WITH 2-(DIMETHYLAMINO)ETHANETHIOL

In order to improve the bioavailability of curcumin, studies have been undertaken to prepare the so-called monocarbonyl analogs of curcumin (MACs) and assess their biological activity. These analogs contain an electrophilic & alpha;,& beta;-unsaturated carbonyl moiety (Michael acceptor). Several key biological processes are connected/controlled with thiol alkylation (glutathione, cysteine, cysteine peptide residues). The most likely reaction is the Michael addition between the & alpha;,& beta;-unsaturated acceptor and a corresponding thiol. 2,6-Bisarylidenecyclohexanone and 3,5-bisarylidenepiperidin-4-one scaffolds offer convenient tunability of electrophilicity and redox properties of the Michael acceptor by the introduction of various substituents. In this study, several MACs were prepared by Claisen-Schmidt condensation reaction, and their reactivity with 2-(dimethylamino)ethanethiol was evaluated. For this purpose, based on the UV-Vis spectra of the analogs and thiol(s), a proper method for spectrophotometric evaluation of their reactivity with 2-(dimethylamino)ethanethiol was optimized. The relative reactivity of the analogs was 7 > 2 > 5 > 4 > 1 & AP; 6. The developed method is simple, and it can be extended to assess the reactivity of other MACs.

Automated summary

To enhance the bioavailability of curcumin, researchers have developed monocarbonyl analogs of curcumin (MACs) with an electrophilic α,β-unsaturated carbonyl group and evaluated their biological activity. The MACs can react with thiol compounds to regulate important biological processes. In this study, MACs were synthesized through Claisen-Schmidt condensation reaction and their reactivity with 2-(dimethylamino)ethanethiol was assessed using a spectrophotometric method based on UV-Vis spectra.