Synthesis, structural characterization and biological evaluation of mononuclear transition metal complexes of zwitterionic dehydroacetic acidN‐aroylhydrazone ligand

Abstract

Synthesis and characterization of mononuclear transition metal complexes viz., Co(II), Ni(II), Cu(II) and Zn(II) with a newly designed ligand, (E)-2-benzamido-N'- (1-(2-hydroxy-6-methyl-4-oxo-4H-pyran-3-yl) ethylidene) benzohydrazide (H 2 L) are reported. Molecular structures of H 2 L, Ni(II) and Cu(II) complexes were determined by single-crystal X-ray diffraction studies. The structures were stabilized by various intra/inter-molecular H-bonding, C-H···π and π···π stacking interactions. H 2 L exists in zwitterionic form and acts in a monoanionic manner. Ligand/metal ratio was 2:1 for cobalt, nickel and zinc, whereas 1:1 for the copper complex. Co(II), Ni(II) and Zn(II) complexes display distorted octahedral geometry, while the Cu(II) complex shows distorted square pyramidal geometry around the metal ion. Hirshfeld surface analysis and 2D fingerprint plots revealed that H 2 L and its complexes were supported mainly by H⋯H, O⋯H and C⋯H intermolecular interactions. The synthesized compounds were screened for in vitro anti-inflammatory activity by gelatin zymography and the activity was comparable with tetracycline. Their cleavage behavior towards calf thymus DNA has been studied using agarose gel electrophoresis method. H 2 L and Cu(II) complex were selected by National Cancer Institute (NCI) for in vitro single dose testing in the full NCI 60 cell lines panel assay. Finally, molecular docking simulation effectively proves the binding of all the synthesized compounds at cyclooxygenase-2 (COX-2) active sites. KEYWORDS(E)-2-amino-N'-(1-(2-hydroxy-6-methyl-4-oxo-4H-pyran-3-yl)ethylidene) benzohydrazide, antiinflammatory and anticancer activity, molecular docking, single crystal X-ray diffraction study, transition metal complexes

An all-rounder aminoguanidine based ligand, its unusual anionic zinc(ii) and cadmium(ii) coordination complexes and their biological implications

“…The geometric parameter τ values 39 of 0.35 and 0.19 respectively for complexes 1 and 2 indicate distorted square pyramidal geometries. 40 The Zn1–Cl2 and Cd1–Cl2 bonds are found to be the longest whereas the Zn1–O1 and Cd1–O1 bonds are the shortest in their coordination spheres. The coordination around the complex is fascinating in several respects.…”

Dehydroacetic acid a privileged medicinal scaffold: A concise review

“…Kendur et al reported the synthesis of some complexes of transition metals Co(II), Ni(II), Cu(II), and Zn(II) with DHA N-aroylhydrazones. [106] The ligand 82 and the complexes were examined for in vitro anti-inflammatory activity, anticancer activity, ions. [107] All the compounds were examined for their DNA photocleavage on plasmid DNA by gel electrophoresis.…”

“…Kendur et al reported the synthesis of some complexes of transition metals Co(II), Ni(II), Cu(II), and Zn(II) with DHA N ‐aroylhydrazones. [ 106 ] The ligand 82 and the complexes were examined for in vitro anti‐inflammatory activity, anticancer activity, and DNA cleavage studies. The anti‐inflammatory study revealed that the metal complex 83 is more active against ligand MMP‐9 with inhibition of 70% as compared to the ligand 82 having 45 % inhibition potential.…”

Synthesis and Properties of Chalcones Based on Dehydroacetic Acid

“…Metal complexes have also been widely studied not only with dehydroacetic acid [17][18][19] but also with its derivatives -Schiff bases [20][21][22][23][24][25] and other various O, N, S donor ligands [26][27][28]. For dehydroacetic acid and its derivatives, antimicrobial [15,29], antitumor [30,31], antiviral, in particular, anti-HIV activity [16,32,33], etc., are widely studied.…”