Current Organic Chemistry - Volume 28, Issue 12, 2024

This survey provides information on the synthesis and biological applications of coumarinyl-chalcones. Chalcones are unsaturated ketones involving the reactive ketoethylenic group (CO-CH=CH). Chalcones are naturally abundant in many medical plants, including vegetables, fruits, and foods. Natural and synthetic chalcone compounds exhibit a broad spectrum of biological properties like anticancer, anti-inflammatory, anti-HIV, antioxidant, antimalarial, and antimicrobial. Some conventional, microwave, and grinding techniques have been utilized for the synthesis of chalcones. Noteworthy, the Claisen- Schmidt condensation reaction remains the most popular and effective method for synthesis. It summarizes information about its synthetic methods as building blocks in some reactions like cyclization reactions and medical applications. This review article presents an overview of approaches and biological data for chalcones bearing a coumarin scaffold.

Recently, the concept of mechanoredox chemistry has been proposed and welldeveloped in organic synthesis. Mechanoredox chemistry is conceptually similar to a photocatalyst reaction system, where piezoelectric materials are introduced to the reaction system in a manner analogous to photoredox catalysis. These reactions feature the ability to generate high-value radicals that do not require harsh reaction conditions of anhydrous and anaerobic conditions, an expensive photocatalyst, and the use of solvents, which renders these transformations highly industrially applicable. In addition, mechanoredox chemistry is also an emerging interdisciplinary research field that combines material chemistry with synthetic chemistry to create more useful reactions. This review provides a comprehensive summary of progress to date in the specific transformation and related mechanisms of piezoelectric- mediated mechanoredox reactions by ball milling in organic synthesis.

Nowadays, polyheterocyclic moieties are playing an important role in drug discovery. Many natural products contain a wide variety of polyheterocycles. Very recently among many other polyheterocycles, benzo[a]phenazine skeleton has gained huge attention due to their broad range of pharmacological efficacies which include anti-plasmodial, antitumor, antimalarial, anticancer, etc. activities. Interestingly, benzo[a]phenazin-5-ol derivatives have been used further as a template for the synthesis of structurally diverse biologically promising polyheterocycles under various reaction conditions. In this review, we have summarized all the recent developments related to the synthesis of structurally diverse biologically promising polyheterocycles involving benzo[a]phenazin-5-ol as a starting reagent or as an intermediate.

Chirality is a widespread structural characteristic found in nature and plays a vital role in the structure and functioning of almost all biological systems. Nevertheless, the translation of chirality into synthetic systems is highly intricate yet captivating, as it not only applies fundamental understanding but also has the potential to tackle significant difficulties in biochemistry and medicine. Structurally, the process of coordination-driven selfassembly involves the organization of basic molecular components into well-defined porous homochiral metal-organic cages (MOCs). This allows for a systematic investigation of the enantioselective processes occurring within the nanocavities, which have limited space and specific chiral microenvironments. This article aims to provide a comprehensive summary of the recent advancements in supramolecular chirality generated in the fascinating class of porous MOCs. It will cover the synthesis and characterization of these materials, as well as the implications of their stereochemical information in terms of chiral recognition and enantio-separation. Subsequently, a subjective viewpoint will be presented regarding the potential, possibilities, and significant challenges in the future advancement of this domain, aiming to expand the progress in creating novel chiral functional materials in the realm of chemistry and beyond.

Synthesis of new hybrid organosilicon compounds based on the amides 1- naphthylacetic acid was described. N-Organyl-2-(1-naphthyl)-N-[(triethoxysilyl)methyl]- acetamides were obtained by the reaction of 1-naphthylacetyl chloride with α-silylamines RNHCH2Si(OEt)3 (R = Me, i-Pr and Ph). Their subsequent interaction with N(CH2CH2OH)3 led to the formation of N-organyl-2-(1-naphthyl)-N-(silatranylmethyl)acetamides. The structure of these hybrid compounds was characterized by ¹H, ¹³C, and ²⁹Si NMR spectroscopy. The structure of N-methyl- and N-isopropyl-2-(1-naphthyl)-N-(silatranylmethy)acetamides was confirmed by X-ray diffraction analysis. Results of computational screening showed that these silatranes are bioavailable and have drug-likeness.

Anthraquinone moiety is very common among naturally occurring bioactive compounds. Many commercially available drug molecules also possess anthraquinone moiety. In recent times, among many other anthraquinone derivatives, specifically, 2- substituted-1H-anthra[1,2-d]imidazole-6,11-diones are gaining extra attention due to their significant anti-cancer, anti-HIV, anti-inflammatory activities, etc. This study aimed to report a simple, straightforward, organocatalyzed method for the efficient synthesis of a series of 2-aryl/heteroaryl/alkyl-1H-anthra[1,2-d]imidazole-6,11-diones from the reactions of 1,2-diaminoanthraquinone and various aldehydes using a catalytic amount of camphorsulfonic acid as an efficient organocatalyst in aqueous ethanol under refluxed conditions. Under the same optimized reaction conditions, along with aryl or heteroaryl aldehydes, aliphatic aldehydes also underwent a smooth reaction and afforded the desired products in excellent yields. All the synthesized compounds were obtained pure in excellent yields by simple filtration and washing subsequently with ethanol. The use of less toxic solvent, low-cost, commercially available metal-free organocatalyst, no column chromatographic separation, good yields, and easy isolation procedure are some of the major advantages of this newly developed protocol.