Green route for efficient synthesis of metal complexes of 4-bromo-2-((E)-((2-hydroxyphenyl)imino)methyl)-6-((E)-(3-nitrophenyl)diazenyl)phenol and its anti-hyperglycemia, anticancer and antimicrobial assessment

The world is battling cancer and diabetes, prompting global research into effective drugs. Studies show coordination compounds, especially substituted salicylaldehydes, exhibit strong biological activity, which increases when treated with amines. In the presented article, The preparation of metal complexes involving Mn(II), Co(II), Ni(II), Cu(II), Zn(II), and VO(II) was carried out using a Schiff base ligand that had been previously synthesized by grinding method of (E)-5-bromo-2-hydroxy-3-((3-nitrophenyl)diazenyl)- benzaldehyde and 2-aminophenol. The synthesized Schiff base ligand confirmed by mass spectra, 1H-NMR spectra, FT-IR spectra. After the confirmation of the Schiff base ligand, synthesis of metal complexes by using metal salt of Mn(II), Co(II), Ni(II), Cu(II), Zn(II) and VO(II). The synthesized metal complexes were analysed by elemental analysis, FT-IR spectra, electronic spectra, thermal analysis, X-ray powder diffraction, molar conductivity etc. For the biological studies, anti-hyperglycaemia and anticancer assessments of Schiff base ligand and metal complexes by alpha amylase inhibition assay and MTT assay against standard reference drug acarbose and 5-flourouracil (5-FU) respectively. The findings of the anti-hyperglycaemia suggest that Co(II) shows higher activity than other metals as well as all metal complexes shows significant activity than free ligand. In the anticancer activity it is clear that Co(II) shows higher activity than other meal complexes as well as all metal complexes shows higher activity than that of free ligand. In addition to this, the antimicrobial properties were examined against two Gram-positive bacterial strains (Staphylococcus aureus and Bacillus subtilis), two Gram-negative bacterial strains (Klebsiella pneumoniae and Pseudomonas aeruginosa), and three fungal strains (Penicillium chrysogenum, Trichoderma viride, and Aspergillus niger). From all the result and observations, it is clear that metal complexes exhibit higher biological assessments than that of Schiff base ligand.