Preparation, Characterization and Study of Color Stability with the Biological activity of Azo Dye Precursors and Schiff Bases Derived from Salicylaldehyde

Abstract

In this study, derivatives of azo dyes (R1-R3) were prepared by preparing diazonium salt (prepared from the reaction of 4-aminoacetophenone or 3-aminopyridine with hydrochloric acid and sodium nitrite) and then coupling it with Salicylaldehyde dissolved in a basic solution, at a temperature of (0-5) ℃. Schiff base-azo derivatives (R4-R7) were synthesized by reacting equimolar amounts of the prepared azo dye compounds (R1, R2) with various substituted amines. Then, the accuracy of the structures of the prepared compounds were diagnosed and confirmed using physical and spectroscopic methods for the prepared compounds, such as infrared spectroscopy (FT-IR) and proton and carbon nuclear magnetic resonance spectra (¹H,¹³C-NMR). In addition to determining the melting points of the prepared compounds. The dyeing or color stability of azo dye derivatives (R1-R3) was studied in two steps. In the first step, the fibers are cleaned by removing impurities; dust stuck in them and shortening processes. Then, in the second step, the dyeing process is carried out by dissolving the dye. In the solvent 1.4-dioxane for dyeing pieces of cotton, wool, and wood. The biological activity of selected compounds was evaluated by studying their effects on the growth of two bacterial strains: Escherichia coli (G-) and Staphylococcus aureus (G+). Amoxicillin was used as a control antibiotic, and some of the prepared compounds exhibited significant inhibitory activity against the tested bacteria. The effect of some prepared compounds on the growth of one type of fungus, which is Candida albicans, was studied. Antibiotics such as Fluconazole and Itraconazole were used as control samples, and some of the prepared compounds showed good inhibitory activity against the fungus used.