ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Single-crystal X-ray, spectroscopy, quantum chemical calculations, and molecular docking investigation of ruthenium (II) polypyridyl complexes of curcumin as a potential chemotherapy drug in the treatment of malignant glioblastoma (GBM)

Abdullahi O. Rajee, Joshua A. Obaleye, Hitler Louis, Abdulbasit A. Aliyu, Amudat Lawal, Ismail O. Amodu, Rawlings A. Timothy, Sheriff O. Ayinla, Kareemat T. Adesope, and Amanda-Lee E. Manicum

Department of Chemistry, Faculty of Physical Sciences, University of Ilorin, Ilorin, Nigeria

E-mail: olarajee@unilorin.edu.ng

Received: 1 July 2023  Accepted: 26 October 2023

Abstract:

Two ruthenium polypyridyl complexes of the type [Ru(N^N)₂(curc)](PF₆) where curc = curcumin; [(1E,6E)-1,7-bis(4-hydroxy-3-methoxyphenyl-1,6-heptadiene-3,5-dione)] and N^N = 2,2′-bipyridine (bpy, R1) and 1,10-phenanthroline (phen, R2) were synthesized. Spectroscopic methods and elemental analyses were employed to characterize them. It was revealed by the T Single-crystal X-ray crystallography that the solid-state structure of compound R1 as the hexafluorophosphate to be triclinic with space group P-1, a = 12.7668(4) Å, b = 13.9159(5) Å, c = 24.1777(8) Å, β = 91.466(2)^o, V = 4233.1(2) Ǻ³, Z = 6. Four nitrogen atoms of the polypyridyl ligands and two oxygen atoms of the β-diketone group, respectively, formed the coordinates of Ru(II) center, and in turn forming a distorted octahedral geometry. The experiments have been compared to be in agreement with the theoretical vibrational wave numbers of the synthesized compounds. Density functional theory (DFT) at the ωB97XD/gen/def2svp/LanL2DZ level of theory has been further utilized in evaluating the structural and electronic properties. Against two different GBM proteins (6bft and 6s79), the binding affinities of the studied compounds and the standard drug (temozolomide) were obtained through the in silico molecular docking approach. R1@6bft, R1@6s79, R2@6bft and R2@6s79 reflect higher binding affinities of − 7 kcal/mol, − 10 kcal/mol, − 8 kcal/mol and − 12 kcal/mol, respectively, in comparison to the commercial drug with binding affinities of − 5 kcal/mol (Temo@6bft) and − 6.0 kcal/mol (Temo@6s79). With the results obtained, it is evident to mention that the compounds and their derivatives could be used as a potential chemotherapeutic drug for the treatment of glioblastoma or as a precursor for the synthesis of other pharmaceutical products.

Keywords: Ruthenium(II) complex; Crystal structure; Curcumin; DFT; Molecular docking; Glioblastoma

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-023-03184-6

Chemical Papers 78 (3) 1567–1583 (2024)