Innovative chromene-based disperse dyes for concurrent dyeing: molecular docking, biochemical assessment, and repellent efficacy against Culex pipiens mosquitoes

Abstract

Integrating a heterocyclic component into the azo dye framework substantially improves the bioactivity of the synthesized compounds. This structural modification facilitates the optimization of drug-like molecules for diverse biological and pharmacological applications. A synthetic route was adopted in this study to develop the target compounds, specifically the 4H-chromene containing azo benzophenones 6a–d, and their behavior on polyester fabrics was examined by optimizing the dyeing conditions. An increase in the color strength of the dyed polyester fabrics was observed with rising dyeing temperatures (100–130 °C) and prolonged dyeing durations (15–60 min). These results imply that synthetic dyes are viable options for adding a wide range of colors to polyester fabrics. In addition to their dyeing performance, bioassay evaluations demonstrated that dyes 6a–d possess repellent efficacy against the mosquito vector Culex pipiens. Compound 6a exhibited the highest repellent activity, reaching approximately 60% after 30 minutes of treatment and maintaining effectiveness for two hours, with a slight decline to 56%. In contrast, compounds 6b, 6c, and 6d showed repellent effects of 53–44%, 56–45%, and 35–44%, respectively. The toxicological potential of these dyes was further investigated by assessing the performance of acetylcholinesterase (AChE) along with glutathione S-transferase (GST) enzymes in Culex pipiens insects following exposure. The synthesized 4H-chromene-based azo dyes show promise for polyester coloration and as bioactive agents with mosquito-repellent and enzyme-inhibitory effects.