Green synthesis and biological significance of chromone derivatives with amino acid and their metal complexes as antimicrobial, anti-diabetic and anti-oxidant

A new organic compound designed by reaction of 3-formyl-6-methylchromone with alanine amino acid and its metal chelates of Ni(II), Fe(II), Co(II), Zn(II) and Zr(IV) ions were synthesized by employing two approaches i.e. green method (microwave irradiation)and conventional method that further compared with each other. All compounds were characterized with various physical analysi (melting point determination, elemental analysis, molar conductance measurement, magnetic moment determination), chemical analysis and various spectral techniques i.e., UV-Vis, FTIR, 1H NMR, Mass spectra and evaluated for in vitro antimicrobial (antifungal: C. albicans, T. reesei; antibacterial: B. subtilis, S. aureus, E. coli), anti-diabetic and anti-oxidant activities. Synthesized compounds were investigated for their thermal stability and crystallinity through thermogravimetric analysis and powder-XRD technique. All analytical data suggested that the 3d series transition metal complexes have tetrahedral geometry and Zr(IV) complex has octahedral geometry. Fe(II) complex exhibited good to moderate both antibacterial and antifungal activity against all selected pathogens. Other metal complexes has shown almost similar antimicrobial potential as ligand. Among all synthesized compounds Ni(II) complex displayed highest anti-diabetic (IC50 = 61.71 mg/L) and anti-oxidant activity (IC50 = 592.38 mg/L). Other metal chelates are less effective for anti-diabetic and anti-oxidant activity compared to ligand.