Stilbenes, like resveratrol, are natural small molecules with several applications in the treatment of chronic illnesses, diabetes, and neurological and cardiovascular conditions. Considering the molecular structure of stilbenes and the biological activities of resveratrol, we investigated the synthesis and biological activity of a novel styryl quinolinium (SQ) derivative. The SQ was synthesized using the alkylation of lepidine and methyl 4-methylbenzenesulfonate and further Knoevenagel condensation with 2-hydroxy naphthaldehyde. Its structure was determined using NMR, IR, Raman, UV-Vis, and MS. The current trend of research has shifted toward the synthesis of novel SQ as resveratrol’s analog. Therefore, its anti-inflammatory and antioxidant activities were evaluated. The compound exerted very good anti-inflammatory effects in preventing albumin denaturation, which were confirmed by ex vivo immunohistochemical studies. Density functional theory (DFT) analyses were conducted on the SQ structure to gain detailed insights into its active sites, energy gap, quantum properties, and electronic behavior. The biological evaluation of the compound was completed, assessing its antioxidant potential using DPPH radical scavenging assay. In addition, molecular docking simulations were utilized to assess the SQ compound’s potential inhibitory effect on human serum albumin (HSA).

Type II topoisomerases (TOP2s) play a key role in altering the DNA topology by transiently cleaving both strands of a DNA duplex. Therefore, increased TOP2 activity is associated with many cancers. Herein, we present the synthesis, structural characterization, virtual screening, and structural exploration, as well as evaluation of the antiproliferative effects of two new 4-substituted 2-(5,5-dimethyl-3-styrylcyclohex-2-enylidene)malononitrile derivatives with potential application in the drug design of isoform-specific TOP2 inhibitors. Both compounds 1 and 2 were verified by ESI-TOF-MS, NMR, and single-crystal X-ray diffraction (SCXRD) analysis. Furthermore, we applied our recently proposed SCXRD/HYdrogen DEsolvation (HYDE) technology platform in order to perform molecular modeling, virtual screening, and structural exploration with 1 and 2. For this purpose, we used the crystal structure of human TOP2β complexed to DNA and the anticancer drug etoposide. Moreover, we further evaluated the antiproliferative activity of 1 and 2 on human hepatocarcinoma HepG2 cells and compared the observed effects with those of the reference hTOP2β inhibitor etoposide. Based on the obtained results, compounds 1 and 2 showed a virtually higher binding affinity (K_{i HYDE} values) over etoposide towards hTOP2β but lower antiproliferative activity compared to those of etoposide.

Propane-1,3-diaminium squarate dihydrate, C₃H₁₂N₂ ²⁺·C₄O₄ ²⁻·2H₂O, results from the proton-transfer reaction of propane-1,3-diamine with squaric acid and subsequent crystallization from aqueous medium. The title compound crystallizes in the tetragonal crystal system (space group P4bm) with Z = 2. The squarate dianion belongs to the point group D _4h and contains a crystallographic fourfold axis. The propane-1,3-diaminium dication exhibits a C _2v -symmetric all-anti conformation and resides on a special position with mm2 site symmetry. The orientation of the propane-1,3-diaminium ions makes the crystal structure polar in the c-axis direction. The solid-state supramolecular structure features a triperiodic network of strong hydrogen bonds of the N—H...O and O—H...O types.

The title compound [systematic name: 1,10-phenanthrolinium 6-hydroxy-5-(oxidoimino)-1,3-diazinane-2,4-dione–6-hydroxy-5-(hydroxyimino)-1,3-diazinane-2,4-dione–water (1/1/5)], C₁₂H₉N₂ ⁺·C₄H₂N₃O₄ ⁻·C₄H₃N₃O₄·5H₂O, is a co-crystal salt hydrate comprising 1,10-phenanthrolinium cations, violurate anions, free violuric acid as co-former and five water molecules of crystallization per formula unit. The violurate and the violuric acid residues each form distinct N—H...O hydrogen-bonded tapes with a common R ² ₂(8) hydrogen-bond motif extending parallel to (103). Solvent water molecules connect the tapes to form a tri-periodic hydrogen-bonded network with channels extending parallel to the a-axis direction, which accommodate the N—H...O_water hydrogen-bonded 1,10-phenanthrolinium cations. Direct N—H...O hydrogen bonds between the 1,10-phenanthrolinium and violurate ions are not encountered.