Acetylacetone and imidazole coordinated Re(I) tricarbonyl complexes: Experimental, DFT studies, and molecular docking approach

Abstract

The research work presents the synthesis, spectral characterization (UV, FT-IR, and NMR), and modelling of tricarbonyl rhenium complexes (R1, R2, R3, R4, and R5) bearing the β-diketone ligand and acetylacetone (Acac) for potential application as cancer drugs. The theoretical investigation was carried out within the framework of density functional theory (DFT) computation at the ωB97XD/Gen/6–311++G (d,p)/LanL2DZ level of theory. The studied rhenium complexes: fac-[Re(Acac)(CO)3(H2O)] (R1),fac-[Re(Acac)(CO)3(Py)] (R2), fac-[Re(Acac)(CO)3(Im)] (R3), fac-[Re(Acac)(CO)3(1-CH3Im)] (R4),fac-[Re(Acac)(CO)3(Pz)] (R5) follows an increasing pattern of stability: R5 < R4 < R2 < R3 < R1, with energy gap values of 6.4487, 6.6281, 7.6758, 7.7487 and 8.0608 eV respectively. The MolDock score ranges from -65.769 to -42.141 kcal/mol compared to the much smaller value of -13.191 kcal/mol for Cisplatin (Cispt) interaction with 2ES3, indicating that the rhenium complex ligands exhibit higher inhibitory activities against TNC to promote apoptosis and regulate cell cycle associated with breast cancer compared to Cispt. The highest score is R4 at -115.954 with HBond energy of -2.923 kcal/mol, then followed by R2 with a score of -103.773 and H-Bond energy bond of -0.392 kcal/mol due to only Steric interaction and R3 with a score of -102.885 and H-bond of -0.2259 kcal/mol due to steric interaction with Phe16(I), Val17(I), Cys53(B) amino acid similar to R2. Due to their stability and MolDock score, R2 and R3 complexes exhibit the potency to be used as potential anti-breast cancer drug participants.