Benzaldehyde derivatives with functional propargyl groups as α-glucosidase inhibitors

Synthesis, DNA Binding Properties, Molecular Docking and ADME Studies of Schiff Base Compound Containing Pyridine-Propargyl Group

The structure of the pyridine-based Schiff base compound containing the propargyl group was characterized by NMR spectroscopy. Binding of compound 2 with double-stranded fish sperm DNA (Fsds-DNA) was investigated using viscosity measurement studies and UV/VIS and fluorescence spectral techniques. Binding of compound 2 with Fsds-DNA results in minor hypochromism with no change in absorption maxima and fluorescence quenching with almost no shift in emission maxima, which can be attributed to the groove-binding mode of the interaction. The binding constant was found to be 4.7×104  M-1 . The Fsds-DNA viscosity measurement, KI quenching and NaCl quenching studies and the competitive interaction between compound 2 and ethidium bromide with DNA confirm the proposed binding mode. In addition, interactions between compound 2 and the DNA double helix were analysed by molecular docking study in order to determine the binding mode and binding affinity. As a result of molecular docking, the binding affinity of the 2-DNA complex, which has the most stable conformation -8.10 kcal/mol and it is located in its minor groove. In addition, molecular docking and ADME studies for compound 2 were also performed.

Synthesis, Structural Investigations, DNA/BSA Interactions, Molecular Docking Studies, and Anticancer Activity of a New 1,4-Disubstituted 1,2,3-Triazole Derivative

We report herein a new 1,2,3-triazole derivative, namely, 4-((1-(3,4-dichlorophenyl)-1H-1,2,3-triazol-4-yl)methoxy)-2-hydroxybenzaldehyde, which was synthesized by copper(I)-catalyzed azide-alkyne cycloaddition (CuAAC). The structure of the compound was analyzed using Fourier transform infrared spectroscopy (FTIR), 1H NMR, 13C NMR, UV-vis, and elemental analyses. Moreover, X-ray crystallography studies demonstrated that the compound adapted a monoclinic crystal system with the P21/c space group. The dominant interactions formed in the crystal packing were found to be hydrogen bonding and van der Waals interactions according to Hirshfeld surface (HS) analysis. The volume of the crystal voids and the percentage of free spaces in the unit cell were calculated as 152.10 Å3 and 9.80%, respectively. The evaluation of energy frameworks showed that stabilization of the compound was dominated by dispersion energy contributions. Both in vitro and in silico investigations on the DNA/bovine serum albumin (BSA) binding activity of the compound showed that the CT-DNA binding activity of the compound was mediated via intercalation and BSA binding activity was mediated via both polar and hydrophobic interactions. The anticancer activity of the compound was also tested by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay using human cell lines including MDA-MB-231, LNCaP, Caco-2, and HEK-293. The compound exhibited more cytotoxic activity than cisplatin and etoposide on Caco-2 cancer cell lines with an IC50 value of 16.63 ± 0.27 μM after 48 h. Annexin V suggests the induction of cell death by apoptosis. Compound 3 significantly increased the loss of mitochondrial membrane potential (MMP) levels in Caco-2 cells, and the reactive oxygen species (ROS) assay proved that compound 3 could induce apoptosis by ROS generation.

N-substituted benzenesulfonamide compounds: DNA binding properties and molecular docking studies

Benzenesulfonamide-based imine compounds 5-8 were prepared and screened for their binding properties to the FSdsDNA. The structures of synthesized compounds were elucidated by the spectroscopic and analytical methods. Compounds 5-8 were screened for their interactions with the FSdsDNA. Compound 8 showed the highest binding affinity to the FSdsDNA with intrinsic binding constant of 3.10 × 104 M-1. The compounds caused the quenching of the DNA-EB emission indicating displacement of EB (ethidium bromide) from the FSdsDNA. Finally, the binding interactions between the DNA and binder molecules 5-8 were examined by the molecular docking studies. The compounds locate approximately same region of the minor groove of DNA via hydrogen bonding contacts between the sulfonamide oxygen atoms and the DG10/DG16 nucleotides of DNA.Communicated by Ramaswamy H. Sarma.

Regioselective alkylation of 2,4-dihydroxybenzyaldehydes and 2,4-dihydroxyacetophenones

We report a cesium bicarbonate-mediated alkylation of 2,4-dihydroxybenzyaldehyde and 2,4-dihydroxyacetophenone to generate 4-alkylated products in acetonitrile at 80 °C with excellent regioselectivity, up to 95% isolated yields, and broad substrate scope.

Potential thiosemicarbazone-based enzyme inhibitors: Assessment of antiproliferative activity, metabolic enzyme inhibition properties, and molecular docking calculations

A new series of thiosemicarbazone derivatives (1-11) were prepared from various aldehydes and isocyanates with high yields and practical methods. The structures of these compounds were elucidated by Fourier transform infrared, ¹ H-nuclear magnetic resonance (NMR), ¹³ C-NMR spectroscopic methods and elemental analysis. Cytotoxic effects of target compounds were determined by 2,3-bis-(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide assay and compound 1 showed significant cytotoxic activity against both MCF-7 and MDA-MB-231 cells, with half-maximal inhibitory concentration values of 2.97 μM and 6.57 μM, respectively. Moreover, in this study, the anticholinergic and antidiabetic potentials of these compounds were investigated. To this aim, the effect of the newly synthesized thiosemicarbazone derivatives on the activities of acetylcholinesterase (AChE) and αglycosidase (α-Gly) was evaluated spectrophotometrically. The title compounds demonstrated high inhibitory activities compared to standard inhibitors with K_i values in the range of 122.15-333.61 nM for α-Gly (K_i value for standard inhibitor = 75.48 nM), 1.93-12.36 nM for AChE (K_i value for standard inhibitor = 17.45 nM). Antiproliferative activity and enzyme inhibition at the molecular level were performed molecular docking studies for thiosemicarbazone derivatives. 1M17, 5FI2, and 4EY6, 4J5T target proteins with protein data bank identification with (1-11) compounds were docked for anticancer and enzyme inhibition, respectively.