Topics in Current Chemistry最新文献

In this review, we present a systematic and comprehensive summary of the recent developments in the synthetic strategies of 2-(2-hydroxyarylsubstituted)-benzothiazole (HBT) framework along with incorporation of various substituents on phenolic and benzothiazole rings which affect the emission process. The literature, spanning the years 2015-2024, on excited-state intramolecular proton transfer (ESIPT)-based studies of HBT derivatives comprising the effects of solvent polarity, substituents, and extended conjugation on fluorophores has been searched. ESIPT, intramolecular charge transfer, and aggregation-induced emissions enable these fluorescent probes to specifically interact with analytes, thereby altering their luminescence characteristics to achieve analyte detection. These fluorescent probes exhibit large Stokes shifts, high quantum yields, and excellent color transitions. Finally, the applications of HBTs as ESIPT-based fluorescent probes for the detection of cations, anions, and biomolecules have been summarized. We anticipate that this review will provide a comprehensive overview of the current state of research in this field and encourage researchers to develop novel ESIPT-based fluorophores with new applications.

Chalcone is a simple naturally occurring α,β-unsaturated ketone with biological importance, which can also be easily synthesized in laboratories by reaction between two aromatic scaffolds. In plants, chalcones occur as polyphenolic compounds of different frameworks which are bioactive molecules that have been in traditional medicinal practice for many years. Chalcone-based lead molecules have been developed, possessing varied potentials such as antimicrobial, antiviral, anti-inflammatory, anticancer, anti-oxidant, antidiabetic, antihyperurecemic, and anti-ulcer effects. Chalcones contribute considerable fragments to give important heterocyclic molecules with therapeutic utilities targeting various diseases. These characteristic features have made chalcone a topic of interest among researchers and have attracted investigations into this widely applicable structure. This review highlights the extensive exploration carried out on the synthesis, biotransformations, chemical reactions, hybridization, and pharmacological potentials of chalcones, and aims to provide an extensive, thorough, and critical review of their importance, with emphasis on their properties, chemistry, and biomedical applications to boost future investigations into this potential scaffold in medicinal chemistry.

Graphdiyne (GDY) is a new variant of nano-carbon material with excellent chemical, physical and electronic properties. It has attracted wide attention from researchers and industrialists for its extensive role in the fields of optics, electronics, bio-medics and energy. The unique arrangement of sp-sp² carbon atoms, linear acetylenic linkages, uniform pores and highly conjugated structure offer numerous potentials for further exploration of GDY materials. However, since the material is at its infancy, not much understanding is available regarding its properties, growth mechanism and future applications. Therefore, in this review, readers are guided through a brief discussion on GDY's properties, different synthesis procedures with a special focus on surface functionalization and a list of applications for GDY. The review also critically analyses the advantages and disadvantages of each synthesis route and emphasizes the future scope of the material.

Indole, a ubiquitous and structurally versatile aromatic compound, has emerged as a key player in the synthesis of diverse heterocyclic frameworks via cycloaddition reactions. These reactions are completely atom-economical and, hence, are considered as green reactions. This review article provides a comprehensive overview of the pivotal role played by indole in the construction of complex and biologically relevant heterocyclic compounds. Here we explore the chemistry of indole-based cycloadditions, highlighting their synthetic utility in accessing a wide array of heterocyclic architectures, including cyclohepta[b]indoles, tetrahydrocarbazoles, tetrahydroindolo[3,2-c]quinoline, and indolines, among others. Additionally, we discuss the mechanistic insights that underpin these transformations, emphasizing the strategic importance of indole as a building block. The content of this article will certainly encourage the readers to explore more work in this area.

Cancer is one of the major noncommunicable diseases, responsible for millions of deaths every year worldwide. Though various cancer detection and treatment modalities are available today, many deaths occur owing to its late-stage detection and metastatic nature. Noninvasive detection using luminescence-based imaging tools is considered one of the promising techniques owing to its low cost, high sensitivity, and brightness. Moreover, these tools are unique and valuable as they can detect even the slightest changes in the cellular microenvironment. To achieve this, a fluorescent probe with strong tumor uptake and high spatial and temporal resolution, especially with high water solubility, is highly demanded. Recently, several water-soluble molecules with emission windows in the visible (400–700 nm), first near-infrared (NIR-I, 700–1000 nm), and second near-infrared (NIR-II, 1000–1700 nm) windows have been reported in literature. This review highlights recently reported water-soluble small organic fluorophores/dyes with applications in cancer diagnosis and therapeutics. We systematically highlight and describe the key concepts, structural classes of fluorophores, strategies for imparting water solubility, and applications in cancer therapy and diagnosis, i.e., theragnostics. We discuss examples of water-soluble fluorescent probes based on coumarin, xanthene, boron–dipyrromethene (BODIPY), and cyanine cores. Some other emerging classes of dyes based on carbocyclic and heterocyclic cores are also discussed. Besides, emerging molecular engineering methods to obtain such fluorophores are discussed. Finally, the opportunities and challenges in this research area are also delineated.

The synthesis of thioether derivatives has been explored widely due to the potential application of these derivatives in medicinal chemistry, pharmaceutical industry and material chemistry. Within this context, there has been an increasing demand for the environmentally benign construction of C–S bonds via C–H functionalization under metal-free conditions. In the present article, we highlight recent developments in metal-free sulfenylation that have occurred in the past three years. The synthesis of organosulfur compounds via a metal-free approach using a variety of sulfur sources, including thiophenols, disulfides, sulfonyl hydrazides, sulfonyl chlorides, elemental sulfur and sulfinates, is discussed. Non-conventional strategies, which refer to the development of thioether derivatives under visible light and electrochemically mediated conditions, are also discussed. The key advantages of the reviewed methodologies include broad substrate scope and high reaction yields under environmentally benign conditions. This comprehensive review will provide chemists with a synthetic tool that will facilitate further development in this field.

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Silicone surfactants have garnered significant research attention owing to their superior properties, such as wettability, ductility, and permeability. Small-molecular silicone surfactants with simple molecular structures outperform polymeric silicone surfactants in terms of surface activity, emulsification, wetting, foaming, and other areas. Moreover, silicone surfactants with small molecules exhibit a diverse and rich molecular structure. This review discusses various synthetic routes for the synthesis of different classes of surfactants, including single-chain, “umbrella” structure, double chain, bolaform, Gemini, and stimulus-responsive surfactants. The fundamental surface/interface properties of the synthesized surfactants are also highlighted. Additionally, these surfactants have demonstrated enormous potential in agricultural synergism, drug delivery, mineral flotation, enhanced oil recovery, separation, and extraction, and foam fire-fighting.

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Organoselenium compounds have been the subject of extensive research since the discovery of the biologically active compound ebselen. Ebselen has recently been found to show activity against the main protease of the virus responsible for COVID-19. Other organoselenium compounds are also well-known for their diverse biological activities, with such compounds exhibiting interesting physical properties relevant to the fields of electronics, materials, and polymer chemistry. In addition, the incorporation of selenium into various organic molecules has garnered significant attention due to the potential of selenium to enhance the biological activity of these molecules, particularly in conjunction with bioactive heterocycles. Iodine and iodine-based reagents play a prominent role in the synthesis of organoselenium compounds, being valued for their cost-effectiveness, non-toxicity, and ease of handling. These reagents efficiently selenylate a broad range of organic substrates, encompassing alkenes, alkynes, and cyclic, aromatic, and heterocyclic molecules. They serve as catalysts, additives, inducers, and oxidizing agents, facilitating the introduction of different functional groups at alternate positions in the molecules, thereby allowing for regioselective and stereoselective approaches. Specific iodine reagents and their combinations can be tailored to follow the desired reaction pathways. Here, we present a comprehensive review of the progress in the selenylation of organic molecules using iodine reagents over the past decade, with a focus on reaction patterns, solvent effects, heating, microwave, and ultrasonic conditions. Detailed discussions on mechanistic aspects, such as electrophilic, nucleophilic, radical, electrochemical, and ring expansion reactions via selenylation, multiselenylation, and difunctionalization, are included. The review also highlights the formation of various cyclic, heterocyclic, and heteroarenes resulting from the in situ generation of selenium intermediates, encompassing cyclic ketones, cyclic ethers, cyclic lactones, selenophenes, chromones, pyrazolines, pyrrolidines, piperidines, indolines, oxazolines, isooxazolines, lactones, dihydrofurans, and isoxazolidines. To enhance the reader’s interest, the review is structured into different sections covering the selenylation of aliphatic sp²/sp carbon and cyclic sp² carbon, and then is further subdivided into various heterocyclic molecules.

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Organophosphorus compounds have long been considered valuable in both organic synthesis and life science. P(III)-nucleophiles, such as phosphites, phosphonites, and diaryl/alkyl phosphines, are particularly noteworthy as phosphorylation reagents for their ability to form new P-C bonds, producing more stable, ecofriendly, and cost-effective organophosphorus compounds. These nucleophiles follow similar phosphorylation routes as in the functionalization of P-H bonds and P-OH bonds. Activation can occur through photocatalytic, electrocatalytic, or thermo-driven reactions, often in coordination with a Michaelis-Arbuzov-trpe rearrangement process, to produce the desired products. As such, this review offers a thorough overview of the phosphorylated transformation and potential mechanisms of P(III)-nucleophiles, specifically focusing on developments since 2010. Notably, this review may provide researchers with valuable insights into designing and synthesizing functionalized organophosphorus compounds from P(III)-nucleophiles, guiding future advancements in both research and practical applications.

Halide perovskite nanocrystals (HPNCs) are currently among the most intensely investigated group of materials. Structurally related to the bulk halide perovskites (HPs), HPNCs are nanostructures with distinct chemical, optical, and electronic properties and significant practical potential. One of the keys to the effective exploitation of the HPNCs in advanced technologies is the development of controllable, reproducible, and scalable methods for preparation of materials with desired compositions, phases, and shapes and low defect content. Another important condition is a quantitative understanding of factors affecting the chemical stability and the optical and electronic properties of HPNCs. Here we review important recent developments in these areas. Following a brief historical prospective, we provide an overview of known chemical methods for preparation of HPNCs and approaches used to control their composition, phase, size, and shape. We then review studies of the relationship between the chemical composition and optical properties of HPNCs, degradation mechanisms, and effects of charge injection. Finally, we provide a short summary and an outlook. The aim of this review is not to provide a comprehensive summary of all relevant literature but rather a selection of highlights, which, in the subjective view of the authors, provide the most significant recent observations and relevant analyses.