Synthesis of novel 4-thiazolidinone derivatives <i>via</i> one-pot three-component reaction of maleimide, thiosemicarbazide, and Meldrum’s acid

The synthesis of novel thiazolidinone derivatives via the three-component reaction has been developed involving the reaction of thiosemicarbazide with maleimide and Meldrum’s acid in a single pot. Optimization of reaction conditions was studied with different solvents and quantities of raw materials. The optimum results were obtained when the reaction was carried out in the ratio (2:2:1 mmol) of maleimide, thiosemicarbazide, and Meldrum’s acid, in the presence of two drops of triethylamine in ethanol. The products were formed with good yields with a significant decrease in reaction time. The structures of thiazolidinones were elucidated by 1H, 13C NMR, FT-IR spectroscopy, HRMS, and X-ray diffraction.