Microwave Irradiated Synthesis of Pyrimidine Containing, Thiazolidin-4-ones: Antimicrobial, Anti-Tuberculosis, Antimalarial and Anti-Protozoa Evaluation

Aims: This study aims to synthesize thiazolidine-4-one compounds with a pyrimidine nucleus and evaluate against different species of bacteria, fungi, protozoa, and the malaria parasite. Background: Microwave irradiation was the best method for synthesizing the thiazolidin-4-one ring system. It took only 15 minutes for synthesizing thiazolidin-4-one while the conventional method required 12 hours. The rapid reaction was the main concern of this research. Objective: Pyrimidine and Thiazolidin-4-one nucleus have broad-spectrum biological activity and when it is introduced with other hetero atoms containing moiety, many types of biological activities have been found; antimicrobial, anti-tuberculosis, anti-protozoa, antimalarial are the main activities. The activity of these compounds inspired us to do extra research on Thiazolidin-4-one fused pyrimidines with different functional groups. The aim of this study is to synthesize a combination of these two ring systems in less time by using a microwave irradiation method and to evaluate new compounds for different bioactivity. Methods: 2-(4-Chlorophenyl)-3-(4-(substituted phenyl)-6-(substituted aryl) pyrimidin-2-yl) thiazolidin-4-ones (6_A-J) were synthesized by microwave irradiation to save energy and time. The structure of all newly synthesized motifs was characterized by spectral analysis (¹H NMR,¹³C NMR, IR, spectroscopy) and screened for antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Streptococcus pyogenes, antifungal activity against Candida albicans, Aspergillus niger, Aspergillus clavatus, anti-tuberculosis activity against M. tuberculosis H37RV, antimalarial activity against Plasmodium falciparum and anti-protozoa activity against L. mexicana and T. cruzi. Results: Because of microwave irradiation synthesis, time period is very less for preparing the new compound. Biological response given by compounds 6_B, 6_C, 6_D, 6_E, 6_G, 6_H, and 6_J was found excellent. Conclusion: Good yield with purity of the newly synthesized thiazolidine-4-one compounds obtained in less time by using microwave irradiation. The biological response of some of the compounds of this series was found excellent.