4-Phenylbutyric acid based homo-heteroleptic Zn(II) carboxylates: Synthesis, structural elucidation, DNA interaction through spectroscopic and computational methods as well as ALP inhibition study

Abstract

Four new zinc(II) complexes of 4-phenylbutyric acid (HL) including one homoleptic i.e., [Zn(L)2]n (1) and three heteroleptic, i.e., [Zn3(L)6(bipy)2] (2), [Zn(L)2(phen)(H2O)] (3) and [Zn(L)2(Me2Phen)] (4) were synthesized. The solution behavior was investigated through 1H and 13C NMR spectroscopy, which depicted the successful synthesis and purity of the complexes. The solid-state behavior was investigated through FT-IR spectroscopy and the results indicated different types of coordination modes adopted by the carboxylate moiety around the Zn(II) center. Electronic absorption spectra showed typical π–π* absorption bands associated with the aromatic moieties. The structural details of complexes 2, 3 and 4 were further investigated through single crystal X-ray diffraction. The electrochemical data indicated that the compounds were redox active under the experimental conditions. The compound-DNA interaction study was performed through UV–visible spectroscopy, viscometry, cyclic voltammetry and molecular docking studies. A comparison of DNA binding data from all techniques revealed that the ligand HL and complex 1 interacted with DNA through intercalation, whereas complexes 2–4 interacted through intercalation as well as groove binding. The compounds were further investigated for alkaline phosphatase inhibition, where concentration and structural dependent inhibitory effects were observed.