Metal Complexes of Semicarbazone and Thiosemicarbazone with Vanillin and 2-acetyl furan: Synthesis and Characterization with Preliminary Anti-bacterial and Anti-fungal Activities

This study reports the synthesis of ligands, D1 i.e. ((E)-2˗(1-(furan˗2-yl)ethylidene) hydrazine-1˗carbothioamide) and D6 i.e. ((E)-2-(4-hydroxy-3-methoxybenzylidene) hydrazinecarbothioamide), utilizing a green, aqueous-based method. The structural properties and coordination behavior with metal (II) ions were analyzed systematically. Both ligands demonstrated effective bidentate coordination, offering two donor sites for each metal ion and all metal complexes are four coordinated. The biological evaluation indicated that complex M4C means (D6-Copper complex) exhibited significant antibacterial and antifungal activity against E. coli, P. chrysogenum, and F. oxysporum, whereas M4A complex means (D6-Nickel complex) demonstrated notable efficacy against S. aureus. Additionally, the complex M5C i.e. (D1-Copper complex) shown significant anti-bacterial activity with S. aureus and E. coli and, antifungal efficacy against F. oxysporum. The M5D i.e. (D1-Zinc complex) demonstrated significant antifungal efficacy against P. chrysogenum. The findings highlight the potential of these ligands and their complexes in the development of effective metal-based antibacterial and anti-fungal agents.