One-pot synthesis, theoretical study and antimicrobial activity of 5,5′-(1,4-phenylenebis-(methanylylidene))Bis(3-Aryl(Alkyl)-2-thioxoimidazolidin-4-one) derivatives

<p>A simple, facile, and convenient practical method for the one-pot synthesis of pharmaceutically interesting 5,5`-(1,4-phenylenebis-(methanylylidene))bis-thiohydantoins via a three-component condensation reaction of terephthalaldehyde, α-amino acids and isothiocyanates had been developed. The <i>S</i>-alkylated derivatives <b>6a</b> and <b>6b</b> were obtained by the alkylation of the bis-thiohydantoins <b>4a</b> with methyl iodide and/or benzyl chloride in a basic media. The molecular structures of the synthesized compounds were confirmed by their elemental analyses and spectral data (IR, <sup>1</sup>H, <sup>13</sup>C NMR and MS). The assignment of more stable <i>Z</i>- or <i>E</i>-isomers as the major form of <b>4a</b>, <b>6a,</b> and <b>8a</b> was investigated by DFT calculations at B3LYP/6-31+G* level. Some of the prepared compounds were screened for their <i>in-vitro</i> antimicrobial activity. Compounds <b>4a</b>, <b>6 b</b>, <b>8 b</b> and <b>8c</b> exhibited low antibacterial activity against gram-positive bacteria <i>Bacillus cereus</i>. (5<i>Z</i>,5′<i>Z</i>)-5,5′-(1,4-Phenylenebis(methanylylidene))bis(3-benzyl-2-thioxoimidazolidin-4-one) (<b>4b</b>) exhibited good fungicidal activity against <i>Fusarium oxysporum</i>.</p>