Metal based biologically active compounds: Design, synthesis, DNA binding and antidiabetic activity of 6-methyl-3-formyl chromone derived hydrazones and their metal (II) complexes

- A bidentate chromone hydrazone ligand was synthesized.
- Nickel, Copper, Zinc (II) complexes were synthesized and characterized by spectral and analytical methods.
- The spin Hamiltonian parameters of some complexes were calculated and discussed.
- The complexes exhibited distorted geometrical arrangements.
- The ligand and metal (II) complexes showed antidiabetic and DNA binding activity.

Two chromone hydrazone ligands HL1 and HL2 were synthesized and characterized by elemental analyses, IR, 1H NMR & 13C NMR, electronic absorption and mass spectra. The reactions of the chromone hydrazones with transition metals such as Ni, Cu, and Zn (II) salts of acetate afforded mononuclear metal complexes. Characterization and structure elucidation of the prepared chromone hydrazone metal (II) complexes were done by elemental, IR, electronic, EPR spectra and thermo gravimetric analyses as well as conductivity and magnetic susceptibility measurements. The spectroscopic data showed that the ligand acts as a mono basic bidentate with coordination sites are azomethine nitrogen and hydrazonic oxygen, and they exhibited distorted geometry. The biological studies involved antidiabetic activity i.e. enzyme inhibition of α-amylase and α-glucosidase, Calf Thymus - DNA (CT-DNA) interaction and molecular docking. Potential capacity of synthesized compounds to inhibit the α-amylase and α-glucosidase activity was assayed whereas DNA interaction studies were carried out with the help UV-Vis absorption titration and viscosity method. The docking studies of chromone hydrazones show that they are minor groove binders. Complexes were found to be good DNA - intercalates. Chromone hydrazones and its transition metal complexes have shown comparable antidiabetic activity with a standard drug acarbose.

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