Synthesis and Biological Activity of New Heterocyclic Compounds Derived from Diamine Derivatives

The new compounds synthesized by sequential reactions starting from a diamine 4-(4-aminophenyl)thiazol-2-amine 1 (which results from the reaction of 4-aminoacetophenon and thiourea with iodide), the compound 1 was reacted with chloroacetic acid to yield 2-(4-(4-(Carboxymethylamino)phenyl)thiazol-2-ylamino)acetic acid 2. While the 5-((4-(4-((5-amino-1,3,4-thiadiazol-2-yl)methylamino)phenyl)thiazol-2-ylamino)methyl)-1,3,4-thiadiazol-2-amine 3 was obtained from the reaction of compound 2 with thiosemicarbazide in POCl3. Finally reacted the compound 3 with different aromatic aldehydes or ketone to produce Schiff bases compounds 4a–4f. The synthesized derivatives characterized via FT-IR, 1H NMR and mass spectroscopy. The biological activity of the synthesized compounds was evaluated against two types of bacteria gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) as well as against one type of fungus, the results show moderate activity against the bacteria under study.