Curcuminoid Chalcones: Synthesis and Biological Activity against the Human Colon Carcinoma (Caco-2) Cell Line.

Abstract

There are many current scientific reports on the synthesis of various derivatives modelled on the structure of known small-molecular and natural bioactive compounds. Curcuminoid chalcones are an innovative class of compounds with significant therapeutic potential against various diseases and they perfectly fit into the current trends in the search for new biologically active substances. The aim of this study was to design and synthesise a series of curcuminoid chalcones. The objective of this scientific paper was to synthesise twelve curcuminoid chalcones and confirm their structures using spectral methods. Additionally, the biological activity of three of the synthesised compounds was evaluated using various assays, and their anticancer properties and toxicity were studied. The proposed derivatives were obtained via the Claisen-Schmidt reaction of selected acetophenones and aldehydes in various conditions using both classical methods: the solutions and solvent-free microwave (MW) or ultrasound (US) variants. The most optimal synthetic method for the selected curcuminoid chalcones was the classical Claisen-Schmidt condensation in an alkaline (NaOH) medium. Spectral methods were used to confirm the structures of the compounds. The resazurin reduction assay, caspase-3 activity assay, and RT-qPCR method were performed, followed by measurements of the intracellular reactive oxygen species (ROS) level and the lactate dehydrogenase (LDH) release level. Twelve designed curcuminoid chalcones were successfully synthesized and structurally confirmed by NMR, MS, and IR spectroscopy. Examination of the anticancer activity was carried out for the three most interesting chalcone products. The results suggested that compound 3a increased the metabolism and/or proliferation of the human colon carcinoma (Caco-2) cell line, while compounds 3b and 3f showed significant toxicity against the Caco-2 cell line. Overall, the preliminary results suggested that compound 3b exhibited the most favourable anticancer activity.