Acid-catalyzed condensation of resorcinol, 2-methyl-resorcinol, and pyrogallol with 2-(4-formylphenoxy)ethyl methanesulfonate in a CHCl3/CF3CO2H or MeOH/HClconc medium led to new rccc and rctt calix[4]resorcinol diastereomers bearing methanesulfonate fragments in high yields, with diasteromeric ratio depending on the nature of the solvent and acid used, as well as their proportions. The obtained compounds can be easily O-alkylated with propargyl bromide, and the subsequent click reaction with BnN3 afforded new multi-functionalized triazole-containing derivatives. Screening against some cancerous and normal cell lines revealed a leading compound, rccc pyrogallol derivative, which exhibited cytotoxic activity against M-HeLa cancer cells at the level of the reference drug Sorafenib.

A modular approach for dual organelle targeting is developed using sterically hindered phenol-diaminopyridine-oxaazacyclononyne (SHP-DAP-OACN) thiourea-linked hybrids. These hybrids retain high reactivity in strain-promoted azide-alkyne cycloaddition, providing fluorescent triazoles with mitochondria and endoplasmic reticulum localization, suggesting SHP-DAP as a transferable module for organelle-directed probes.

The article describes a new method for the synthesis of functionalized nitrogen-containing alpha, beta-unsaturated compounds based on the reaction of 3-arylidene-1-pyrrolines with various N -nucleophiles. The proposed method allows the preparation of alpha, beta-unsaturated compounds containing fragments of imine, hydrazone, N- methyleneacetohydrazide, N -methylenehydrazine-1-carboxamide, and N -methylenehydrazine-1-carbothioamide. The proposed method is distinguished by mild reaction conditions and the possibility of using various solvents, including water. The yield of the obtained products reaches 99%. The possibility of selective photoisomerization at the C=C bond was demonstrated, making them candidates for further study as photoswitches. The obtained compounds can be used as pH-activated molecular switches. alpha, beta-Unsaturated hydrazides showed good cytotoxicity toward normal and cancer human cell lines.

In this work, we report the one-pot synthesis and characterization of four water-soluble 2-hydroxybenzo[e][1,2]oxaphosphinine 2-oxides. The compounds were obtained by cascade reactions of (2-ethoxyvinyl)phosphonic dichloride with phenol or naphthol derivatives, and their acid–base, structural, and photophysical properties were investigated using a combination of experimental and computational methods. These compounds exhibit UV–vis absorption maxima at 209–341 nm and fluorescence maxima at 300–394 nm. Notably, these cyclic phosphonic acids exhibit unusually strong acidity with pKa values from −1.3 to 0, comparable to mineral acids; complete protonation is not achieved even in concentrated HCl. The acidity trends and spectra were further analyzed by DFT using both explicit and implicit solvation models.

A method was developed for the synthesis of new unsymmetrical cage phosphonates containing terminal halo(bromo, chloro)methyl groups as a result of the reaction of (2-ethoxyvinyl)phosphonic dichloride with halogen-N-(3-hydroxyphenyl)acetamides in trifluoroacetic acid. New cage phosphonates containing one or two phosphonium groups were obtained as a result of the reaction of triphenylphosphine with the corresponding cage phosphonates. It was shown that the type of products formed in this reaction depends on the nature of the halogen atom in the halomethyl group of the cage phosphonate.

New phosphacoumarins containing an aldehyde group at the periphery were obtained in a 'one-pot' reaction of 2-ethoxyvinylphosphonic dichloride with 2,4-dihydroxy-benzaldehyde derivatives. The further reaction of these compounds with 2,4-dinitrophenylhydrazine afforded new hydrazones which exist only as E-isomers.

Meldrum's acid-based multi-component reactions have emerged as a highly versatile and valuable tool, offering simple access to numerous classes of pharmaceutically and industrially valuable heterocyclic and acyclic organic compounds. The vast majority of these reactions employ a carbonyl compound as one of the reagents and utilize the electrophilic reactivity of transient arylidene malonates. This necessarily requires a third nucleophilic reagent and represents the general limitation of these reactions. Herein, we proposed an approach to a reactivity umpolung of arylidene malonates via a visible light-driven SET/PT sequence, enabling the radical chemistry in Meldrum's acid-based MCRs. The viability of the proposed approach was demonstrated by the three-component synthesis of hitherto unknown imidazolinone malonic acids. The radical chain mechanism was evidenced for the disclosed transformation by mechanistic experiments and density functional calculations.

New phosphonium salts synthesized from 5-chloromethyl-8-methyl-7-azacoumarin-3-carboxamides and triphenylphosphine upon the Wittig reaction with aromatic aldehydes give the corresponding 5-styryl-7-azacoumarin derivatives. The cytotoxic activity of some phosphonium salts against cancer cell lines M-HeLa and HuTu-80 is equal to or superior to that of the reference 5-fluorouracil. The IC50 and SI values of the leading compounds exceed those for 5-fluorouracil by a factor of 3.7 and 2.2, respectively.

Background/Objectives: The development of antitumor agents possessing low toxicity against non-cancerous cells is still a challenge in medicinal chemistry. In this paper, we report the antitumor activity of “hybrid structures” derived from the amino acid taurine. We have synthesized 26 compounds, structures of which were confirmed using NMR, X-ray diffractometry, and other techniques. Cytotoxicity of the obtained compounds has been evaluated using three human cancer cell lines. Pyrrolidine 4p has exhibited the strongest antiproliferative activity against HL-60 cells with an IC50 of 76.7 μM, while IC50 against normal cells was 176.3 μM. Water-soluble derivatives of taurine have been tested for antileukemia activity in mice of the BDF1 line. Compound 4p has been identified as the leading compound, which increases the mean survival time of mice from 40 to 100% as compared to the control group. Together, these results prove that taurine-based hybrid structures can be a promising scaffold for the discovery of potential antiproliferative agents.

Aliphatic amines containing N-heterocyclic fragments reacted with dialkyl [3,5-di-tert-butyl-4-oxo-2,5-cyclohexadienylidene)methyl] phosphonates to form 1,6-nucleophilic addition products. This approach was used to obtain α-aminophosphonates containing sterically hindered phenol and N-heterocyclic fragments in high yields. All the compounds were evaluated for their in vitro cytotoxicity with various cancer cell lines by MTT assay method. In the course of biological studies, it was found that the obtained compounds possess cytotoxic activity against some tumor cells.

In contrast to hypervalent iodine compounds, the chemistry of their sulfur analogues has been considerably less explored. Herein, we report the direct C-H bond thiolation of electron-rich heterocycles, arenes, and 1,3-dicarbonyls by dichlorosulfuranes under mild conditions. Mechanistic studies and density functional theory calculations suggest the radical chain mechanism of the disclosed transformation. The key to success is attributed to a strikingly low S-Cl bond dissociation energy, which enables the generation of radical species upon exposure to daylight.

A method was developed for synthesizing previously unknown hydrazones containing two pharmacophoric fragments in their structure based on the reaction of phenyl/acylhydrazines with 1-(1-tosylpyrrolidin-2-yl)propan-2-one. Structure of the resulting hydrazones was established using 1H, 13C NMR, IR spectroscopy, and mass spectrometry (ESI-TOF) data. Based on 1D/2D correlation NMR experiments, it was found that the resulting hydrazones exist only as E-isomer.

Reactions between 4-(propargyloxy)benzaldehyde with anthracene-9-carbaldehyde oxime or pyrene-1-carbaldehyde oxime in the presence of chloramine T in ethanol lead to new isoxazole-containing derivatives of benzaldehyde. The subsequent acid-catalyzed condensation of these compounds with 2-methylresorcinol in chloroform/trifluoroacetic acid mixtures affords novel calix[4]resorcinols with anthaceneand pyrene-ended isoxazole-containing fragments as all–cis (rccc) and cis–trans–trans (rctt) diastereoisomers, their ratios being dependent on the CF3CO2H percentage in the medium. The crystal structures of pyrene-ended isoxazole-containing benzaldehyde and corresponding calix[4]resorcinol rctt isomer have been established by single crystal X-ray diffraction.

A method was developed for the synthesis of first representative of unsymmetrical cage phosphonates containing a carbonyl group on the periphery. New hydrazones were prepared by the reaction of 3-hydroxy-4,8,9,11-tetramethyl-12H-6,12-methanodibenzo[d,g][1,3,2]dioxaphosphocine-2-carbaldehyde-6-oxide with hydrazines and hydrazides (phenylhydrazine, benzohydrazide, nicotinic hydrazide, isonicotinic acid hydrazide). Composition and structure of all the obtained compounds were confirmed by 1H, 13С and 31P NMR, IR spectroscopy, mass spectrometry and X-ray structural analysis. Based on 1D/2D correlation NMR experiments, it was found that the resulting hydrazones exist only as E-isomer.

Alkaloids are predominantly nitrogen-containing heterocyclic compounds that are usually isolated from plants, and sometimes from insects or animals. Alkaloids are one of the most important types of natural products due to their diverse biological activities and potential applications in modern medicine. Cyclic imines were chosen as starting compounds for the synthesis of alkaloids due to their high synthetic potential. Thus, this review summarizes the achievements in the synthesis of various alkaloids from cyclic imines, paying special attention to stereoselective methods used for their preparation. Information on the biological activity of some alkaloids, their application and occurrence in natural objects is presented. Synthesis methods are classified based on the type of alkaloid obtained.

A new phosphaneoflavonoid was obtained by the reaction oxaphosphinine with β-resorcylic acid. A method was proposed for the synthesis of new unsymmetrical cage phosphonates based on 4-aryl-2-hydroxy-5,7,8-trimethylbenzo[e][1,2]oxaphosphinine-2-oxides as a result of intramolecular heterocyclization. Composition and structure of all the obtained compounds were confirmed by 1H, 13С and 31P NMR, IR spectroscopy and mass spectrometry data.

A method was proposed for the regioselective synthesis of new 2,3-disubstituted quinolines based on the reaction of anilines with 4-chloro-1,1-diethoxybutane and N-(4,4-diethoxybutyl)tosylamide. Structure of the resulting compounds was proven by NMR spectroscopy techniques (1H, 13C, 15N, COSY, HSQC 1H–13C, HMBC 1H–13C, HMBC 1H–15N, NOESY), the composition was confirmed by elemental analysis data. The proposed method is distinguished by the possibility of obtaining a wide range of substituted quinolines in one step and the absence of the need to use expensive metal catalysts.

Many phytopathogens' gene products that contribute to plant-pathogen interactions remain unexplored. In one of the most harmful phytopathogenic bacterium Pectobacterium atrosepticum (Pba), phosphonate-related genes have been previously shown to be among the most upregulated following host plant colonization. However, phosphonates, compounds characterized by a carbon-phosphorus bond in their composition, have not been described in Pectobacterium species and other phytopathogenic bacteria, with the exception of Pseudomonas syringae and Pantoea ananatis. Our study aimed to determine whether Pba synthesizes extracellular phosphonates and, if so, to analyze their physiological functions. We demonstrated that Pba produces two types of extracellular phosphonates: 2-diethoxyphosphorylethanamine and phenylphosphonic acid. Notably, such structures have not been previously described among natural phosphonates. The production of Pba phosphonates was shown to be positively regulated by quorum sensing and in the presence of pectic compounds. Pba phosphonates were found to have a positive effect on Pba stress resistance and a negative effect on Pba virulence. The discovered Pba phosphonates are discussed as metabolites that enable Pba to control its "harmful properties", thereby maintaining its ecological niche (the host plant) in a relatively functional state for an extended period.

The presented review systematizes and summarizes the data on the synthesis of pyrrolidine derivatives, which are precursors for obtaining drugs. Based on the analysis of published data, the most promising directions in the synthesis of biologically active compounds containing a pyrrolidine ring are identified. Stereoselective synthesis methods are classified based on the source of the pyrrolidine ring. The first group includes methods that use a pyrrolidine ring as the starting compound. The second group combines stereoselective methods of cyclization of acyclic starting compounds, which lead to optically pure pyrrolidine derivatives.

A family of bifunctional dihetarylmethanes and dibenzoxanthenes is assembled via a reaction of acetals containing a 2-chloroacetamide moiety with phenols and related oxygen-containing heterocycles. These compounds demonstrated selective antitumor activity associated with the induction of cell apoptosis and inhibition of the process of glycolysis. In particular, bis(heteroaryl)methane containing two 4-hydroxy-6-methyl-2H-pyran-2-one moieties combine excellent in vitro antitumor efficacy with an IC50 of 1.7 µM in HuTu-80 human duodenal adenocarcinoma models with a high selectivity index of 73. Overall, this work highlights the therapeutic potential of dimeric compounds assembled from functionalized acetals and builds a starting point for the development of a new family of anticancer agents.