In recent years, researchers have often encountered the significance of the aberrant metabolism of tumor cells in the pathogenesis of malignant neoplasms. This phenomenon, known as the Warburg effect, provides a number of advantages in the survival of neoplastic cells, and its application is considered a potential strategy in the search for antitumor agents. With the aim of developing a promising platform for designing antitumor therapeutics, we synthesized a library of conjugates of 3,5-bis(arylidene)-4-piperidone and sesquiterpene lactones. To gain insight into the determinants of the biological activity of the prepared compounds, we showed that the conjugates of 3,5-bis(arylidene)-4-piperidone and sesquiterpene lactones, which are cytotoxic agents, demonstrate selective activity toward a number of tumor cell lines with glycolysis-inhibiting ability. Moreover, the results of molecular and in silico screening allowed us to identify these compounds as potential inhibitors of the pyruvate kinase M2 oncoprotein, which is the rate-determining enzyme of glycolysis. Thus, the results of our work indicate that the synthesized conjugates of 3,5-bis(arylidene)-4-piperidone and sesquiterpene lactones can be considered a promising platform for designing selective cytotoxic agents against the glycolysis process, which opens new possibilities for researchers involved in the search for antitumor therapeutics among compounds containing piperidone platforms.

Application of water as a solvent (without any cosolvent) promotes the aza-Michael reaction of diethyl vinylphosphonate and diphenylvinylphosphine oxide with a wide range of N-nucleophiles. The solubility of the starting phosphorus substrate in water does not play a crucial role in the reaction course, decreasing to some extent the reaction rate. The reaction can be performed either at room temperature or under reflux to afford the corresponding β-aminophosphonates and β-aminophosphine oxides in excellent yields and of high purity via a simple freeze-drying isolation procedure. Application of basic catalysts makes possible the addition of weak nucleophiles such as α-amino acids and their phosphorus analogues; that is, α-aminophosphonic acids. The aqueous aza-Michael reaction allowed us to easily perform double phosphorylation of primary amines including polyamines using a reactant ratio (phosphorus substrate: amine) of 2:1.

The paper is devoted to various significant polyatomic and doubly charged interferences observed for trace elements determined by inductively coupled plasma mass spectrometry in geological samples. It has been shown that most interferences can be minimized or completely excluded using an ELEMENT 2 high-resolution mass spectrometer. The influence of spectral interferences has been quantitatively estimated. Recommendations are given for the selection of isotopes with minimal spectral interferences and an optimal resolution mode. The detection limits for analytes are evaluated for three resolution modes: 300, 4000 and 10000 together with the interferences related to the errors of rare-earth element determination.

Facile synthetic approaches to a few novel classes of amidophosphates, ω-aminophosphonates, and bisphosphonates having a 3,5-bis(arylidene)piperid-4-one backbone have been elaborated starting from piperid-4-ones functionalized with phosphorus motives followed by aldol-crotonic condensation with a range of (hetero)aromatic aldehydes or via introduction of the corresponding phosphorus function into the preformed NH-3,5-bis(arylidene)piperid-4-ones. Combination of phosphorus-containing moieties possessing inherent bioactivity and cytotoxic 3,5-bis(arylidene)piperid-4-one moiety resulted in the compounds with high antitumor activity towards human carcinoma cell lines Caov3, A549, Scov3, PC3, KB 3-1, and KB 8–5 (IC₅₀ in the range of 1–80 μM).