Synthesis of novel bioactive amides derived from carbazole moiety with deep-blue and single-component white photoluminescence

Abstract

This work focuses on the chemical synthesis of three fluorescent bioactive amides tethered carbazole moiety by coupling 3-amino-9-ethylcarbazole with different aliphatic carboxylic acids including valeric, hexanoic, and heptanoic acids. NMR spectroscopy and HRMS were utilized to confirm the claimed structure of the target compounds indicating good agreement. The antimicrobial activity of fluorescent amides was assessed against different strains of gram negative and gram-negative bacterial as well as fungi demonstrating outstanding activity close or same as the control. Moreover, the molecular design, DFT calculations, and photoluminescence characteristics of these dyes have been investigated. The examined materials solutions emitted a deep-blue emission. Interestingly, with the powders, on the other hand, a single component emitted white light. The creation of aggregated molecules in the solid state improved the emission intensity at long visible wavelengths, resulting in a change in the emission color from the solution to the powder. The studied materials also emitted consistently at high temperatures. Furthermore, the odd–even effect both on the molecular packing and emission characteristics has been proven. As a result, the molecules under investigation provide a unique combination of benefits: a simple molecular structure, deep-blue emitters, white emission from a single material, and an odd–even effect.