New metal complexes of semicarbazones derived from para phenylene diamine of NOO/or NO donor sites and their antimicrobial screening

The synthesis and characterization of new Mn[II]. Co[II] Ni[II] and Cu[II] complexes with semicarbazone ligands derived from para phenylene diamine [where L[1] = Semicarbazide-4-yl-benzene-4 [2-hydroxybenzalde-hyde semicarbazone] [SBFIBS], L[2] = Betizene-1, 4-bis-[2-hydroxybenz-aldehyde semicarbazone-4yl] [BBHBS], L[3] = Semicarbazide-4yl-benzene-4 [2-hydroxyacetophen-one-semicarbazone] SBHAS and L[4] = Semicarbazide-4yl-benzene-4 [2-nitrobenzaldehyde semicarbazone] [SBNBS]] are reported. The ligands contain NOO/or NO donor sites. The elemental analysis suggests different stoichiometries 1: 2: 1 and 1: 2 [M: L]. IR spectra data indicate covalent bond through the oxygen atom of the hydroxyl group, coordination of the carbonyl oxygen and the azomethine nitrogen / or nitrogen of the amine group to the metal ion. TGA determined whether the water or solvent molecules are inside or outside the coordination sphere. Magnetic susceptibility and electronic data are in favour of octahedral structures except in the case of Co [II] complexes of ligand BBHBS and SBHAS as they favour the tetrahedral structure. The biological activity of the complexes has been tested. These complexes showed promising antifungal activities