Synthesis, computational study, and antibacterial activity of rhodanine and thiazolidine-2,4-dione scaffolds

In this research, different thiazolidine-2,4-dione and 2-thioxothiazolidin-4-one derivatives (1-13) have been synthesized by Knoevenagel Condensation (1-13). Thiazolidine-2,4-dione and 2-thioxothiazolidin-4-one derivatives have an important role in medicinal chemistry and drug design. All synthesized compounds (1-13) have been confirmed by IR, ¹H and ¹³C-NMR spectral data. A computational study was used to determine values of the lowest unoccupied molecular orbital and highest occupied molecular orbital energy gap to show the chemical stability, and reactivity of compounds (1-13). Small values of energy between a lowest unoccupied molecular orbital and a highest occupied molecular orbital energy gap indicate chemical stability and reactivity of synthesized compounds. ELUMO-HOMO ranged between 0.004-0.306 eV indicated high reactivity of the prepared molecule. Thermodynamic energies have been calculated for synthesized compounds including Enthalpy, Entropy, and Gibbs free energy, negative values have been detected for all synthesized compounds (1-13). Antibacterial activity has done for all synthesized compounds (1-13) against Gram-positive Staphylococcus aureus and Gram-negative Escherichia coli by the method of disc diffusion show that all synthesized compounds except 7, 8, 11 and 13 have antibacterial effect for both or one type of bacteria. Antibacterial activity is observed as a clear circular zone of inhibition for selected synthesized compounds by disc Inhibition zones of Staphylococcus aureus, and Escherichia coli bacteria. The range for Staphylococcus aureus were between (6-24 )mm and for Escherichia coli were between (6-18)mm, the measuring of the zones were with the discs.