Synthesis of Thiazole-2(3H)-thiones as Antimicrobial Agents Promoted by H3PW12O40-amino-functionalized CdFe12O19@SiO2 Nanocomposite

H3PW12O40-amino-functionalized CdFe12O19@SiO2 nanocomposite has been utilized as an effective nanocatalyst for the preparation of thiazole-2(3H)-thiones by three-component reactions of CS2, 2-bromoacetophenone or 2-bromo-1-(4-methoxyphenyl) ethenone, and a primary amine in ethanol. H3PW12O40-amino-functionalized CdFe12O19@SiO2 nanocomposites have been identified by powder X-ray diffraction (XRD), scanning electronic microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), vibrating sample magnetometer (VSM), thermal gravimetric analysis (TGA), and Fourier transform infrared (FT-IR) spectroscopy. The compounds 4b (3-(3,4-dichlorobenzyl)-4-phenyl-1,3-thiazole-2(3H)-thione), 4e (3-(4-Fluorobenzyl)-4-phenyl-1,3-thiazole-2(3H)-thione), 4f (3-(2-Methoxybenzyl)-4-phenyl-1,3-thiazole-2(3H)-thione), and 4j (3-(2-Methoxybenzyl)-4-(4-methoxyphenyl)-1,3-thiazole-2(3H)-thione) have moderate growth inhibitory effects on Gram positive bacteria (Staphylococcus aureus, Bacillus subtilis; and Staphylococcus epidermidis). In addition, the compound 4b has moderate growth inhibitory effects on fungi. The salient features of this protocol include great yields in concise times, retrievability of the nanocatalyst, little nanocatalyst loading, and antibacterial activities for four compounds.