New 5-alkyl-1,2,4-triazole-3-thione surfactants with antifungal and silver nanoparticles stabilization activity

Abstract

New 5-alkyl-1,2,4-triazole-3-thiones containing structural fragments of anionic surfactants have been synthesized and examined as stabilizers in the wet chemistry synthesis of silver nanoparticles (AgNPs). The synthesis of the new 1,2,4-triazole-3-thiones was done via the cyclization reaction of 4-acyl-thiosemicarbazides in basic conditions. The structure of the new surfactant was analyzed by spectroscopic (infrared and nuclear magnetic resonance) and theoretical DFT methods. The surface activity characteristic, such as critical micelle concentration, was estimated using the conductivity method and the 1H NMR technique. The structural peculiarities of the new compounds testify to their surfactant properties, which is why they were explored as stabilizers in the chemical synthesis of silver nanoparticles from silver nitrate in an aqueous solution. The UV–VIS spectroscopy technique confirmed the formation of AgNPs in aqueous solutions of 5-alkyl-1,2,4-triazole-3-thiones. The stable AgNPs were obtained only using 1,2,4-triazole-3-thiones with longer alkyl chains (pentadecyl and heptadecyl), whereas the 5-pentyl-1,2,4-triazole-3-thione and the 5-heptyl-1,2,4-triazole-3-thione have not shown considerable stabilization activity. To better understand the interaction of the 1,2,4-triazole-3-thiones with AgNPs, Raman spectra analysis, quantum chemical modeling, and force field molecular dynamics were performed. The new triazoles were studied for their antifungal activity by the determination of minimal inhibition concentrations and docking studies.