A Competition between Hydrogen, Stacking, and Halogen Bonding in N-(4-((3-Methyl-1,4-dioxo-1,4-dihydronaphthalen-2-yl)selanyl)phenyl)acetamide: Structure, Hirshfeld Surface Analysis, 3D Energy Framework Approach, and DFT Calculation

Organoselenocyanates Tethered Methyl Anthranilate Hybrids with Promising Anticancer, Antimicrobial, and Antioxidant Activities

Novel methyl anthranilate-based organoselenocyanate hybrids were developed, and their structures were confirmed by the state-of-the-art spectroscopic techniques. Their antimicrobial potency was estimated against various microbial strains (e.g., Candida albicans, Escherichia coli, and Staphylococcus aureus). The S. aureus and C. albicans strains were more sensitive than E. coli toward the organoselenocyanates. Interestingly, the azoic derivatives 4 and 9, methyl ester 6, and phenoxy acetamide 15 showed promising antimicrobial activity. Moreover, the antitumor potential was estimated against liver and breast carcinomas, as well as primary fibroblasts. Interestingly, the anticancer properties were more pronounced in the HepG2 cells. The organoselenocyanates 4, 6, 9, 10, and 15 showed interesting anti-HepG2 cytotoxic patterns. Additionally, organoselenocyanates 3, 4, and 10 exhibited promising antioxidant activities in the 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid and 2,2-diphenyl-1-picrylhydrazyl in vitro assays compared to ascorbic acid. These data point to promising antimicrobial, anticancer, and antioxidant activities of organoselenocyanates 6, 9, and 15 warrant further studies.

Anticancer, Antimicrobial, and Antioxidant Activities of Organodiselenide-Tethered Methyl Anthranilates

Novel methyl anthranilate-based organodiselenide hybrids were synthesized, and their chemical structures were confirmed by state-of-the-art spectroscopic techniques. Their antimicrobial properties were assessed against Staphylococcus aureus, Escherichia coli, and Candida albicans microbial strains. Moreover, the antitumor potential was estimated against liver and breast carcinomas, as well as primary fibroblast cell lines. The Staphylococcus aureus and Candida albicans strains were more sensitive than Escherichia coli toward the OSe compounds. Interestingly, methyl 2-amino-5-(methylselanyl) benzoate (14) showed similar antifungal activity to the standard drug clotrimazole (IA% = 100%) and manifested promising antibacterial activity against E. coli (IA% = 91.3%) and S. aureus (IA% = 90.5%). Furthermore, the minimum inhibitory concentration experiments confirmed the antimicrobial activity of the OSe 14, which in turn was comparable to clotrimazole and ampicillin drugs. Interestingly, the anticancer properties were more pronounced in the HepG2 cells. The OSe 14 was the most cytotoxic (IC₅₀ = 3.57 ± 0.1 µM), even more than the Adriamycin drug (IC₅₀ = 4.50 ± 0.2 µM), and with therapeutic index (TI) 17 proposing its potential selectivity and safety. Additionally, OSe compounds 14 and dimethyl 5,5'-diselanediylbis(2-aminobenzoate) (5) exhibited promising antioxidants in the 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid (ABTS) and 2,2-diphenyl-1-picrylhydrazyl (DPPH) in vitro assays with 96%, 92%, 91%, and 86% radical scavenging activities compared to 95% by vitamin C in the DPPH and ABTS assays, respectively. These results point to promising antimicrobial, anticancer, and antioxidant activities of OSe 14 and 5 and warrant further studies.

Unexpected kinetically controlled organoselenium-based isomaleimide: X-ray structure, hirshfeld surface analysis, 3D energy framework approach, and density functional theory calculation

Reduction of 4,4′-diselanediyldianiline (1) followed by the reaction with bromo-4-(bromomethyl)benzene afforded the corresponding 4-((4-bromobenzyl)selanyl)aniline (2) in 85% yield. N-Maleanilic acid 3 was obtained in 94% yield via the reaction of selenoamine 2 with toxilic anhydride. Subsequent dehydration of N-maleanilic acid 3 using acetic anhydride furnished the unexpected isomaleimide 5-((4-((4-bromophenyl)selanyl)phenyl)imino)furan-2(5H)-one (4) instead of the maleimide 5. The molecular structure of compound 4 was confirmed by mass spectrometry, ¹H- and ¹³C-NMR spectroscopy, and X-ray diffraction analysis. Their cytotoxicity was assessed against two oligodendrocytes, and their respective redox properties were evaluated using 2′,7′-dichlorodihydrofluorescein diacetate (H2-DCFDA) assay. Furthermore, their antiapoptotic potential was also evaluated by flow cytometry. The compound crystallizes in triclinic P-1 space group with unit cell parameters a = 5.7880 (4) Å, b = 9.8913 (6) Å, c = 14.5951 (9) Å, V = 1731.0 (3) Å³ and Z = 2. The crystal packing is stabilized by intermolecular hydrogen bonding, π···π, C-Br···π stacking interactions, and other non-covalent interactions. The mapping of different Hirshfeld surfaces and 2D-fingerprint were used to investigate intermolecular interactions. The interaction energies that stabilize the crystal packing were calculated and graphically represented as framework energy diagrams. We present a computational investigation of compound 4’s molecular structure at the Density Functional Theory level using the B3LYP method and the 6-31G ++ basis set in this paper. The optimized structure matches the experimental outcome. The global reactivity descriptors and molecular electrostatic potential (M.E.P.) map emphasize the molecule’s reactive locations, allowing reactivity prediction. The charge transfer properties of molecules can be estimated by examining Frontier molecular orbitals.

Novel Organoselenium Redox Modulators with Potential Anticancer, Antimicrobial, and Antioxidant Activities

Novel organic selenides were developed in good yields (up to 91%), and their chemical entities were confirmed by IR, MS, and ¹H- and ¹³C-NMR spectroscopy. Their anticancer and antimicrobial properties were estimated against different human cancer (MCF-7 and HepG2) and healthy (WI-38) cell lines, as well as several microbial strains (Escherichia coli, Staphylococcus aureus, and Candida albicans). Furthermore, the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) bioassays were used for the estimation of the antioxidant activities. Generally, cytotoxicity results were more pronounced against the MCF-7 cells than HepG2 cells. Compound 2-((4-((1-hydroxynaphthalen-2-yl)diazenyl)phenyl)selanyl)-N-phenylacetamide (9) was the most cytotoxic, even more than doxorubicin, with IC₅₀ of 3.27 ± 0.2 against 4.17 ± 0.2 µM and twelve-times more selective, respectively. Interestingly, compound 9 exhibited similar antimicrobial potential to reference antibacterial and antifungal drugs and comparable antioxidant activity to vitamin C. These results point to selective cytotoxicity against MCF-7 cells and interesting antimicrobial and antioxidant properties of some newly synthesized organic selenides, which in turn needs further in vitro studies.

Protonation of Borylated Carboxonium Derivative [2,6-B10H8O2CCH3]−: Theoretical and Experimental Investigation

The process of protonation of [2,6-B10H8O2CCH3]− was investigated both theoretically and experimentally. The most suitable conditions for protonation of the derivative [2,6-B10H8O2CCH3]− were found. The process of protonation was carried out in the presence of an excess of trifluoromethanesulfonic acid CF3SO3H at room temperature in dichloromethane solution. The structure of the resulting complex [2,6-B10H8O2CCH3*Hfac]0 was established using NMR data and the results of DFT calculations. An additional proton atom Hfac was found to be localized on one of the facets that was opposite the boron atom in a substituted position, and which bonded mainly with one apical boron atom. The main descriptors of the B-Hfac bond were established theoretically using QTAIM and NBO approaches. In addition, the mechanism of [2,6-B10H8O2CCH3]− protonation was investigated.