Novel Selenoureas Based on Cinchona Alkaloid Skeleton: Synthesis and Catalytic Investigations

An efficient approach to the synthesis of chiral selenoureas consisting of Cinchona alkaloid scaffolds was described. The new selenoureas were assessed as bifunctional organocatalysts in the asymmetric Michael addition reactions under mild conditions. The best results were obtained for selenoureas bearing the 4-fluorophenyl group. These catalysts promoted the reactions with enantioselectivities of up to 96% ee. Additionally, the catalytic performance of the thiourea and selenourea counterpart was compared

Novel Selenoureas Based on <em>Cinchona</em> Alkaloid Skeleton: Synthesis and Catalytic Investigations

An efficient approach to the synthesis of chiral selenoureas consisting of Cinchona alkaloid scaffolds was described. The new selenoureas were assessed as bifunctional organocatalysts in the asymmetric Michael addition reactions under mild conditions. The best results were obtained for selenoureas bearing the 4-fluorophenyl group. These catalysts promoted the reactions with enantioselectivities of up to 96% ee. Additionally, the catalytic performance of the thiourea and selenourea counterpart was compared

Monoterpenes and Their Derivatives—Recent Development in Biological and Medical Applications

Monoterpenes, comprising hydrocarbons, are the largest class of plant secondary metabolites and are commonly found in essential oils. Monoterpenes and their derivatives are key ingredients in the design and production of new biologically active compounds. This review focuses on selected aliphatic, monocyclic, and bicyclic monoterpenes like geraniol, thymol, myrtenal, pinene, camphor, borneol, and their modified structures. The compounds in question play a pivotal role in biological and medical applications. The review also discusses anti-inflammatory, antimicrobial, anticonvulsant, analgesic, antiviral, anticancer, antituberculosis, and antioxidant biological activities exhibited by monoterpenes and their derivatives. Particular attention is paid to the link between biological activity and the effect of structural modification of monoterpenes and monoterpenoids, as well as the introduction of various functionalized moieties into the molecules in question

Efficacy of Selenourea Organocatalysts in Asymmetric Michael Reactions under Standard and Solvent-Free Conditions

By varying the steric and electronic surroundings of the hydrogen-bonding motif, the novel chiral Cinchona-alkaloid based selenoureas were developed. Acting as bifunctional catalysts, they were applied in the Michael reactions of dithiomalonate and nitrostyrene providing chiral adducts with up to 96% ee. The asymmetric Michael&ndash;-hemiacetalization reaction of benzylidene pyruvate and dimedone, performed with the assistance of 5 mol% of selenoureas, furnished the product with up to 93% ee and excellent yields. The effectiveness of the new hydrogen-bond donors was also proved in solvent-free reactions under ball mill conditions, supporting the sustainability of the devised catalytic protocol

Selected Monocyclic Monoterpenes and Their Derivatives as Effective Anticancer Therapeutic Agents

Terpenes—a diverse group of secondary metabolites—constitute the largest class of natural products abundant in almost every plant species. The properties of concrete terpenes and essential oils have been intensively studied due to their widespread use in the pharmaceutical, food and cosmetics industries. Despite the popularity of these aromatic compounds, their derivatives, terpenoids, are still not comprehensively characterized despite exhibiting potent bioactive properties. This review aims to assess the anticancer properties of selected monoterpenes including carvone, carvacrol, perillyl alcohol, perillaldehyde, limonene, menthol and their derivatives while also evaluating potential applications as novel anticancer treatments. Special attention is paid to functional groups that improve the bioactivity of monoterpene molecules. This review also covers the therapeutic potential of deep eutectic solvents that contain monoterpene substances. Taken together, the literature supports the use of monoterpene derivatives in the development of new alternatives for disease treatment and prevention

Chiral Aziridine Sulfide N(sp3),S-Ligands for Metal-Catalyzed Asymmetric Reactions

A series of new bidentate N,S-ligands—aziridines containing a para-substituted phenyl sulfide group—was synthesized and evaluated in the Pd-catalyzed Tsuji–Trost reaction and addition of diethylzinc and phenylethynylzinc to benzaldehyde. A high enantiomeric ratio for the addition reactions (up to 94.2:5.8) was obtained using the aziridine ligand bearing a p-nitro phenyl sulfide group. Collected results reveal a specific electronic effect that, by the presence of particular electron-donating or electron-withdrawing groups in the PhS- moiety, influences the σ-donor–metal binding and the enantioselectivity of the catalyzed reactions