Synthesis and self-assembly of novel pH triggered smart organogelators from novel alkyl-substituted chalcone-based hydrazonotriazole derivatives

Chalcones have been known as a significant group of compounds used for treatment of parasitic infections, cardiovascular diseases, viral disorders, gastritis, pain, and stomach cancer. Additionally, they have been employed in cosmetic formulation ingredients and food additives. In the current study, a series of new 4-(1-(2-(2,4-dinitrophenyl)hydrazineylidene)ethyl)-5-methyl-1-aryl-1 H -1, 2, 3-triazole derivatives with different terminal alkyl chains were synthesized to function as pH-induced and thermally reversible low molecular weight gelators (LMWG). The novel hydrazonotriazole derivatives were synthesized by a simple reaction of (2,4-dinitrophenyl)hydrazine with various derivatives of 1-(5-methyl-1-(4- alkoxyphenyl)-1 H -1, 2, 3-triazol-4-yl)ethan-1-ones in absolute ethanol using hydrochloric acid as a catalyst. Elemental analysis, FTIR, and NMR spectroscopic techniques were used to prove the molecular structures of the synthesized chalcone-based gelators. The photophysical properties of the synthesized gelators were described. The chalcone-based gelators were found to efficiently gelate various organic solvents with reversible responsiveness ability to pH stimulus, demonstrating a sol–gel switching process in association with a colorimetric shift from yellow to purple. The optimum gelation activity was observed for the nonyloxy-substituted chalcone-based organogelator in various solvents with critical gel concentration (CGC) in the range of 2.05–9.28 mM, and thermal stability up to 46 °C. Various analytical techniques were utilized to examine the morphologies of xerogels, displaying nanofibrous assemblies (10–30 nm). Both cytotoxicity and antibacterial activities of the synthesized alkyl-substituted chalcone-based gelators were explored.