New Imidazolidineiminothione, Imidazolidin-2-one and Imidazoquinoxaline Derivatives: Synthesis and Evaluation of Antibacterial and Antifungal Activities.

A series of new 5-imino-4-thioxo-2-imidazolidinone derivatives with various halogenated and alkylated aromatic substituents at and was synthesized. Imidazolidineiminothione derivatives were prepared from the reaction of arylcyanothioformamide derivatives with aryl isocyanates. These compounds were used as key synthons for the preparation of wide variety of new substituted imidazole compounds. Imine hydrolysis of with ethanolic HCl produced the corresponding 4-thioxo-2,5-imidazolidindiones Condensation of with benzophenonhydrazone furnished the corresponding 4-azine derivatives . Monohydrazono and dihydrazono derivatives and were obtained upon treatment of imidazolidinone derivatives with hydrazine hydrate. Finally, imidazolidinones were reacted with -phenylenediamines or pyrazol-5(4)-ones and afforded the corresponding imidazoquinoxaline and imidazolidin-4-ylidenepyrazolone-5(4)-one derivatives and respectively. Evaluation of the antibacterial and antifungal activities for the synthesized compounds was carried out to probe their activities. Most of the tested compounds showed significant activities. The best antimicrobial activity was observed for 1-(3-ethoxyphenyl)-6-methyl-1-phenyl-1-imidazo[4,5-b]quinoxalin-2(3)-ones followed by 5-imino-3-(3-methoxy- phenyl)-1-phenyl-4-thioxoimidazolidin-2-one .