Synthesis, characterization, crystal structure determination, computational modelling and biological studies of a new tetrakis-(2-hydroxy-5-methylphenyl)(1H-pyrazol-4-yl)methanonezinc(II) complex

A new four-blade-propeller-with-axel kind zinc complex, dichloro-tetrakis-(2-hydroxy-5-methylphenyl)(1H-pyrazol-4-yl)-methanonezinc(II) complex, [Zn(HMPM)(4)Cl-2], has been synthesized and characterized by spectral, structural and biological studies. Its crystal structure was solved by single crystal X-ray diffractometry. The ligand, (2-hydroxy-5-methylphenyl)(1H-pyrazol-4-yl)methanone, (HMPM), has been prepared by condensation of 3-formyl-6-methyl chromone with thiosemicarbazide. The [Zn(HMPM)(4)Cl-2] complex crystallizes in the centrosymmetric monoclinic P2(1)/n space group with unit cell dimensions, a = 13.2068 angstrom, b = 7.0763 angstrom, c = 23.5910 angstrom, beta = 102.327 degrees From the XRD data it follows that [Zn(HMPM)(4)Cl-2] is a slightly distorted octahedral complex with the 4 HMPMs serving as monodentate ligands through their pyrazoles' sp(2) nitrogens and the 2 chlorides occupying the trans positions. Each of the [Zn(HMPM)(4)Cl-2] molecules in the crystal assumes a ci point group of symmetry. Both [Zn(HMPM)(4)Cl-2] and its ligand, HMPM, have been molecular modelled through DFT studies on XTB platform and the computationally obtained structural parameters were found to be in very good agreement with the XRD data. The calculated electronic spectral bands of HMPM and the Zn(II) complex are also found to be very close to the experimental results. The ligand and the complex are also found to exhibit considerable anti-bacterial activity. Protein-docking studies also have been carried out for both HMPM and [Zn(HMPM)(4)Cl-2]. (C) 2022 Elsevier B.V. All rights reserved. (C) 2022 Elsevier B.V. All rights reserved.