Synthesis of some pyridazine derivatives carrying urea, thiourea, and sulfonamide moieties and their antimicrobial activity

Some pyridazine derivatives carrying urea, thiourea, and sulfonamide groups were synthesized and evaluated for their antimicrobial activity against gram-positive and gram-negative bacteria, and fungi by using broth microdilution. The structures of these new compounds were confirmed by $^1H$-NMR, mass spectrum, and elemental analysis. The synthesized compounds exhibited generally promising inhibitory activity against S. aureus (MIC ranging from 2 to 4 μg/mL) and E. coli (MIC ranging from 4 to 16 μg/mL). Moreover, all compounds showed antifungal activity against both C. albicans and C. parapsilosis, with a MIC value of 8 μg/mL.