Synthesis and Bioassay of New Urea and Thiourea Derivatives of 4-Aminobenzohydrazide

A series of new urea 3a–3d and thiourea derivatives 5a–5f have been synthesized in high yields (77–88%) by the reaction of substituted aryl isocyanates 2a–2d and substituted aryl isothiocynates 4a–4f with 4-aminobenzoic hydrazide 1. The structures of all the synthesized compounds were characterized by IR, NMR (¹H and ¹³C), mass and elemental analyses. The synthesized compounds were screened for their anti-microbial activity. The present study revealed that Gram-negative and positive bacteria such as Escherichia coli and Streptococcus aureus were more susceptible to the solvent extracts. The methanol and acetone extracts of the newly synthesized compounds were evaluated for in vitro antibacterial activity against human pathogenic bacteria Escherichia coli and Streptococcus aureus and antifungal activity against Aspergillus niger and Aspergillus oryzae. Compound 5e have exhibited good antibacterial and antifungal activity.