New 14-membered octaazamacrocyclic complexes: Synthesis, spectral, antibacterial and antifungal studies

A novel series of macrocyclic complexes of the type [M(C18H14N10S2)X]X2 where M = Cr(III), Fe(III) and Mn(III); X = Cl−, NO3− and CH3COO− have been synthesized by [2 + 2] condensation of thiocarbohydrazide and isatin in the presence of trivalent metal salts in methanolic medium by template method. The complexes have been characterized with the help of elemental analyses, conductance measurements, magnetic measurements, electronic, NMR, IR and mass spectral studies. On the basis of these studies, a five coordinate square pyramidal geometry for all of these complexes has been proposed. These metal complexes were also tested for their in vitro antimicrobial activities against some bacterial strains viz. Staphylococcus aureus, Bacillus subtilis, Escherichia coli, Pseudomonas aeruginosa and some fungal strains Aspergillus niger, Aspergillus flavus (molds), Candida albicans, Saccharomyces cerevisiae (yeasts).

Graphical abstractA novel series of macrocyclic complexes have been synthesized by template method followed by their characterization by various physicochemical techniques. These metal complexes were tested for their in vitro antimicrobial activities against some bacterial and fungal strains to assess their inhibiting potential.Figure optionsDownload full-size imageDownload as PowerPoint slide