Synthesis, crystal structure, DFT study, in vitro and in silico molecular docking of novel bis (aroyl selenourea) derivatives

Novel N,N'-Disubstituted Selenoureas as Potential Antioxidant and Cytotoxic Agents

A series of 30 novel N,N disubstituted selenoureas were synthesized, characterized, and their antioxidant ability was tested using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzthiazoline-6-sulfonic acid (ABTS) assays. Additionally, their cytotoxic activity was tested in vitro in a panel of three different cancer (breast, lung and colon) and two normal cell lines. Each selenourea entity contains a para-substituted phenyl ring with different electron-withdrawing and electron-donating groups, and different aliphatic and aromatic nuclei. All of the synthesized selenoureas present antioxidant capacity at high concentrations in the DPPH assay, and three of them (2b, 2c and 2d) showed greater radical scavenging capacity than ascorbic acid at lower concentrations. These results were confirmed by the ABTS assay, where these novel selenoureas present even higher antioxidant capacity than the reference compound Trolox. On the other hand, 10 selenoureas present IC₅₀ values below 10 µM in at least one cancer cell line, resulting in the adamantyl nucleus (6a–6e), the most interesting in terms of activity and selectivity. Outstanding results were found for selenourea 6c, tested in the NCI60 cell line panel and showing an average GI₅₀ of 1.49 µM for the 60 cell lines, and LC₅₀ values ranging from 9.33 µM to 4.27 µM against 10 of these cancer cell lines. To gain insight into its anticancer activity mechanism, we investigated the cell cycle progression of the promising compound 6c, as well as the type of programmed-cell death in a colon cancer cell line it provokes (HT-29). Compound 6c provoked S phase cell cycle arrest and the induction of cell death was independent of caspase activation, suggesting autophagy, though this assertion requires additional studies. Overall, we envision that this compound can be further developed for the potential treatment of colon cancer.

Synthesis, characterization, theoretical, molecular docking and in vitro biological activity studies of Ru(II) (η6-p-cymene) complexes with novel aniline substituted aroyl selenoureas

A sequence of aroyl selenourea ligands (L1-L3) substituted by aniline and their Ru(II) (η⁶-p-cymene) complexes (1-3), [Ru(II) (η⁶-p-cymene) L] (L = monodentate aroyl selenourea ligand) have been synthesized and characterized the composition of the ligands and their metal complexes. The molecular structures of ligand L1 and complex 3 were also confirmed by single XRD crystal method. The single-crystal XRD study showed that aroyl selenourea ligand coordinates with Ru via Se novel neutral monodentate atom. In vitro DNA interaction studies were investigated by Fluorescence and UV-Visible spectroscopic methods which showed that the intercalative mode of binding is in the order of 1 > 2 > 3 with Ru(II) (η⁶-p-cymene) complexes. Spectroscopic methods have been used for measuring the binding affinity of bovine serum albumin to complex. Moreover, the cytotoxic study of complexes (1-3) were evaluated against HeLa S3, A549, and IMR90 cells, resulting in complexes 1 and 2 showed promising cytotoxic activity against HeLa S3 cell with IC₅₀ values of 24 and 26 µM, respectively. Also, the morphological changes of HeLa S3 and A549 cells were confirmed by fluorescence microscope in the presence of complexes 1 and 2 using AO (acridine orange, 200 µM) and EB (ethidium bromide, 100 µM). In addition, the docking results strongly support the protein binding studies of the complexes.Communicated by Ramaswamy H. Sarma.