The synthesis of a small library of 8-substituted 2-methyl-5,6,7,8-tetrahydroquinoline derivatives is presented. All the compounds were tested for their antiproliferative activity in non-cancer human dermal microvascular endothelial cells (HMEC-1) and cancer cells: human T-lymphocyte cells (CEM), human cervix carcinoma cells (HeLa), human dermal microvascular endothelial cells (HMEC-1), colorectal adenocarcinoma (HT-29), ovarian carcinoma (A2780), and biphasic mesothelioma (MSTO-211H). Compounds 3a, 5a, and 2b, showing significant IC₅₀ values against the whole panel of the selected cells, were further synthesized and tested as pure enantiomers in order to shed light on how their stereochemistry might impact on the related biological effect. The most active compound (R)-5a was able to affect cell cycle phases and to induce mitochondrial membrane depolarization and cellular ROS production in A2780 cells.

A series of three 1,3-phenylene bis-oxamides 3a–c, structurally related to the GPR35 receptor-agonist drug lodoxamide, has been synthesized by reacting the 1,3-phenylene bis-oxalamates 2a and 2b with amines. The obtained compounds were characterized by ¹H and ¹³C NMR, and IR spectroscopy, they showed characteristic signals for the aromatic, N―H, and C=O groups. Molecular structure was determined using single-crystal X-ray diffraction. The supramolecular architecture is driven by N―H···O=C, N―H···N, C—H···π, and O=C···O=C interactions depicting a supramolecular helix (3a) and tapes (3b–c). Intermolecular interactions were studied using Hirshfeld surface analysis, where N―H∙∙∙X (X = N, O) hydrogen bonding represents 30.2% to the surface of 3a and 17.8–18.8% to the surface of 3b–c. The most energetic interactions involve the amide N—H∙∙∙O hydrogen bonding, contributing in the −113.9 to −97.0 kJ mol⁻¹ range to the crystal energy, being more dispersive than electrostatic in nature. The molecular docking study was performed to evaluate the binding ability of 3a–c compounds to the GPR35 receptor, showing a favorable binding in a similar way to lodoxamide.

Triclosan (TCS) is used in many health care products as a broad-spectrum antimicrobial and disinfectant agent; however, it is currently considered an emerging pollutant. The present study aimed to develop an analytical HPLC method coupled to a Diode Array Detector for the TCS determination in toothpaste. Method development involved the optimization of separation and sample preparation. For chromatographic separation optimization, different RP columns and aqueous mobile phases were addressed. The optimized chromatographic separation was achieved in around 3 minutes using a Symmetry C18 column at 30 °C, 0.6 mL/min flow-rate, and 225 nm wavelength detection. For toothpaste sample preparation optimization a response surface methodology using a Box-Behnken fractional factorial design was chosen. The sample treatment consisted of leaching 0.2 g sample by sonication for 7 minutes using 2 mL of MeOH. According to the International Conference on Harmonization (ICH, 1996/2005) and European Commission Decision 200/657/EC guidelines, the developed method was validated. The developed analytical method was found fast, economic, linear, sensitive, precise, and robust and allowed to quantify TCS in different healthcare products.