Synthesis, Characterization, and Biological Evaluation of 1-(2-oxo-2H-1-benzopyran-4-yl)-1H-1,2,3-triazole-4-carbaldehyde

Coumarins and 1,2,3-triazoles have long been of great interest in medicinal chemistry due to their rich structural diversity and their broad spectrum of biological activities. In this study, we report the synthesis of a molecular hybrid that combines the coumarin and 1,2,3-triazole scaffolds, yielding a compound that incorporates characteristics of both pharmacophores. The hybrid 1-(2-oxo-2H-1-benzopyran-4-yl)-1H-1,2,3-triazole-4-carbaldehyde was synthesized from 4-hydroxycoumarin, a readily accessible starting material. The synthetic sequence begins with azidation to introduce the essential azide functionality, followed by a CuAAC click reaction with propargyl alcohol to furnish the 1,2,3-triazole core. Finally, oxidation leads to the formation of the aldehyde group. Finally, oxidation of the alcohol yields the expected molecular hybrid. The overall isolated yield for the target compound was 59.1%, and its structure was confirmed by ¹H and ¹³C-NMR and infrared spectroscopy. The antibacterial activity of all synthesized compounds was evaluated against a panel of bacteria, including multidrug-resistant strains, to assess potential antimicrobial activity. However, the results showed that they did not exhibit antibacterial effects against any of the tested strains. Nonetheless, the absence of antibacterial activity does not diminish the value of the molecular scaffold; rather, it underscores the possibility of other biological activities and prompts further exploration of alternative targets and pharmacological profiles.