Designing of Antipyrine-Based Azo Dyes with Cyclic Dione Scaffolds for Application in Cotton Dyeing and Microbial Resistance

A series of five novel monoazo dyes designed from 4-amino antipyrine diazo coupling with five different cyclic ketones is successfully reported and characterized by possible spectroscopic methods to confirm their structural appearance. Based on FTIR and 1 H-NMR spectral interpretation, dyes A and E are stable in their tautomer-like hydrazone and enol forms. In this endeavor, dyes were also subjected to an assessment of dyeing performance using high-temperature and high-pressure methods at 130 °C, and the synthesized dyes were found to have good dyeing abilities. Electron withdrawing group carbonyls in the heterocyclic moiety, adjacent to the diazo linkage, influence the shades of the dye on the fabric. The dyed fabric exhibits moderate to favorably good color fastness properties of washing, sublimation, heat, and perspiration. Antimicrobial screening was also performed against two fungal strains and four bacterial strains including Gram-positive and Gram-negative bacteria. The results are negligible for dyes A – D , but dye E possesses moderate to excellent inhibitory actions toward bacterial strain B. subtilis as well as the fungi C. albicans . These pathogens are found to exist on cotton fabrics for a month and induce health issues. Dyed cotton fabrics with dye E is found to be resistant to the fungus C. albicans which bears 14 days of lifespan on cotton fabric and causes nosocomial infections including vaginal yeast sepsis, diaper rashes, and thrush. Graphical Abstract