Abstract

Zn(II) complexes bearing tris[3-(2-pyridyl)-pyrazolyl] borate (Tppy) ligand (1–3) was synthesized and examined by spectroscopic and analytical tools. Mononuclear [TppyZnCl] (1) has a Zn(II) centre with one arm (pyrazolyl-pyridyl) dangling outside the coordination sphere which is a novel finding in TppyZn(II) chemistry. In complex [TppyZn(H2O)][BF4] (2) hydrogen bonding interaction of aqua moiety stabilizes the dangling arm. In addition, solution state behaviour of complex 1 confirms the tridentate binding mode and reactivity studies show the exogenous axial substituents used to form the [TppyZnN3] (3). The complexes (1–3) were tested for their ability to bind with Calf thymus (CT) DNA and Bovine serum albumin (BSA) wherein they revealed to exhibit good binding constant values with both the biomolecules in the order of 104–105 M−1. The intercalative binding mode with CT DNA was confirmed from the UV-Visible absorption, viscosity, and ethidium bromide (EB) DNA displacement studies. Further, the complexes were tested for in vitro cytotoxic ability on four triple-negative breast cancer (TNBC) cell lines (MDA-MB-231, MDA-MB-468, HCC1937, and Hs 578T). All three complexes (1–3) exhibited good IC50 values (6.81 to 16.87 μM for 24 h as seen from the MTS assay) results which indicated that these complexes were found to be potential anticancer agents against the TNBC cells.

Highlights

  • Zinc is the second most abundant metal found in the human body, being vital in regulating cellular process [1,2] including enzyme regulation [3], gene expression [4], apoptosis [5], and neurotransmission [6]

  • An equimolar amount of ZnCl2 and [tris[3-(2-pyridyl)-pyrazolyl] borate (Tppy)]− in a methanolic solution provides a white powder of mononuclear complex [TppyZnCl] (1) (Scheme 1)

  • It is interesting to note that, effective space management around the coordinated metal in tris-pyrazolyl borates can data and molecular geometry for 2 is shown in Figure 1b and the corresponding refinement parameters, bond length and bond angle are given in Tables S1 and S2

Read more

Summary

Introduction

Zinc is the second most abundant metal found in the human body (human being contains average 2–3 g of zinc), being vital in regulating cellular process [1,2] including enzyme regulation [3], gene expression [4], apoptosis [5], and neurotransmission [6]. Compared to other first row transition metals, zinc has certain distinguishing properties which makes it quite challenging in the biological domain [3,7]. The fast exchange with ligands, strong Lewis’s acidity, redox inactiveness, and the capability to endure a versatile coordination geometry are some of the striking features which makes zinc ubiquitous in the biological system [8]. With the above mentioned redox-inert characteristic properties, we find that zinc is functionally closer to the redox-inert magnesium and calcium ions and among the redox-inert divalent metal ions, zinc is the metal that has the strongest interaction with ligand frameworks and biomolecules [12]

Methods
Results
Conclusion

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.