Oxime ethers as useful synthons in the synthesis of a number of key medicinal heteroaromatic compounds

Heteroaromatic systems are not only prevalent in a wide variety of important classes of natural products and synthetic pharmaceuticals but are also used as a building block in organic synthesis. Therefore, synthesis of these compounds using new protocols is always interesting. This review is a survey of the literature describing methods for the synthesis of heteroaromatic compounds from oxime ethers.     

Synthesis of Benzofuran Derivatives via Different Methods

This review presents a systematic and comprehensive survey of the methods of preparation of benzofurans. These compounds are important intermediates for the synthesis of a variety of synthetically useful and novel heterocyclic systems.     

Microwave-assisted synthesis of bioactive quinazolines and quinazolinones

This paper aims to review recent developments in the synthesis of quinazolines and quinazolinone derivatives under conditions that include the application of microwave heating in the ring forming step. Recently, two reviews on the synthesis and chemistry of natural and synthetic quinazolines and quinazolinones have been published. This review highlights significant examples where microwave heating has been either synthetically enabling or has provided a key advantage over conventional thermal methods. Wherever possible, this review will focus on chemistry carried out using monomode systems and well-designed type of instrumentation. The review is grouped according to the main heterocycle types in order of increasing complexity; commencing with quinazolines and their derivatives. The microwave-assisted synthesis of quinazolines and quinazolinones will be classified and based on the substitution patterns of the ring system. Syntheses of heterocyclic systems of particular biological or commercial interest are emphasized.     

Rational design of complex molecular structures starting from readily available precursors

The review summarizes recent advances in the selective synthesis of complex molecular systems starting from simple readily available precursors. Such systems have a great potential for application in pharmacology, medicine, and materials science. The efficiency of the application of catalysis and structural studies for the development of new methods of synthesis is demonstrated.     

Directing transition metal-based oxygen-functionalization catalysis

This review presents the recent progress of oxygen functionalization reactions based on non-electrochemical (conventional organic synthesis) and electrochemical methods. Although both methods have their advantages and limitations, the former approach has been used to synthesize a broader range of organic substances as the latter is limited by several factors, such as poor selectivity and high energy cost. However, because electrochemical methods can replace harmful terminal oxidizers with external voltage, organic electrosynthesis has emerged as greener and more eco-friendly compared to conventional organic synthesis. The progress of electrochemical methods toward oxygen functionalization is presented by an in-depth discussion of different types of electrically driven-chemical organic synthesis, with particular attention to recently developed electrochemical systems and catalyst designs. We hope to direct the attention of readers to the latest breakthroughs of traditional oxygen functionalization reactions and to the potential of electrochemistry for the transformation of organic substrates to useful end products.

This review presents the recent progress of oxygen functionalization catalysis via non-electrochemical (conventional organic synthesis) and electrochemical routes.     

Control of Catalytic Activity Via Porosity,Chemical Composition,and Morphology of Nanostructured Porous Manganese Oxide Materials

This review concerns a summary of synthesis, characterization, and applications of octahedral molecular sieve (OMS) materials. These OMS systems have been the focus of our research program for over 20 years. This review primarily covers the past 10 years with an emphasis on the most recent developments in this area. Some current areas of concern include the systematic synthesis of well ordered materials, control of particle sizes, generation of nano‐size particles, and development of new synthetic methods like pulse laser deposition and epitaxial growth of oxidic materials. Applications include use of OMS in environmental catalysis, adsorption, clean energy materials, activation of the Greenhouse gas carbon dioxide, and selective oxidations. OMS catalysts are outstanding selective oxidation catalysts and can also drive total oxidations. The highly selective of OMS systems may be related to redox cycling and redox catalysis.     

Classical and interdisciplinary approaches to the design of organic and hybrid molecular systems

This review summarizes the recent advances in the construction of organic and hybrid systems having considerable potential for practical applications in pharmacology, medicine, materials science, petrochemistry, and chemistry of high-energy compounds. The methodological classification of the approaches into classical and interdisciplinary is proposed. Examples of the efficient application of these approaches for investigating complex molecular systems, as well as for developing new methods of synthesis are given.     

Gold and silver assisted synthesis of five-membered oxygen and nitrogen containing heterocycles

The investigation of methods for the chemical synthesis is a growing area of interest due to increasing environmental issues. The use of catalysts in organic reactions has gained extensive interest. Metal and nonmetal catalysts provided a new improved alternative to traditional methods in modern synthetic chemistry. The aim of the present review is to focus on the applications of gold- and silver-catalytic systems for the synthesis of five-membered oxygen- and nitrogen-heterocycles.     

Chemistry of 3-(2-Haloacyl)indoles

This review presents a systematic and comprehensive survey of the methods ofpreparation and the chemical reactivity of 3-(2-haloacyl)indoles. These compounds are important intermediates for the synthesis of a variety of otherwise difficult to obtain synthetically useful and novel heterocyclic systems. The data published over the past few years are reviewed here for the first time.     

Bioelectrosynthesis as an alternative to photosynthesis

The CO₂ reduction processes have been discussed as a way of designing an ecologically totally closed technology. An electric current and molecular hydrogen are the two related available agents that can be discussed as ecologically pure reductants. The most important products are liquid and gaseous fuels, the products of large-scale organic synthesis, monomers, and amino acids. For CO₂ reduction, the necessary energy consumption and H₂ costs were calculated. For complex organic molecules, amino acids for instance, the energy consumption does not make up the main portion of the costs. The biocatalytic systems of CO₂ reduction based on cryoimmobilized cells are described. Conversion of CO₂ into L-lysine with electrochemical decomposition of water was effected on the laboratory scale. A general unit for diverse technological processes can be a bioelectrosynthetic Index Entries: Bioelectrosynthesis; CO₂ reduction; liquid fuels; amino acids; immobilized cells; economic estimates. modulus, an electrochemical hydrogen generator coupled with a biocatalytic converter of hydrogen and oxygen. The systems for bioelectrosynthesis of motor fuels and essential amino acids have been economically estimated and characterized. The possibilities of combining the solar energy transformation and H₂–CO₂ conversion have been discussed.     

化学结构正规编码及其信息处理功能

自从计算机在化学领域中应用以来,化学结构的正规编码已广泛用来作为一种化学文献的信息索引,它还在开发化学智能系统中发挥着重要作用。正规编码生成是以化学结构图的拓扑性质为基础的。本文首先概述编码的基本原理及其生成的方法,随后分析这种编码在当今文献数据库、化学反应数据库、分子设计以及合成反应路线规划等化学信息系统中的功能。     

Magnetic nanoparticles: synthesis, protection, functionalization, and application

This review focuses on the synthesis, protection, functionalization, and application of magnetic nanoparticles, as well as the magnetic properties of nanostructured systems. Substantial progress in the size and shape control of magnetic nanoparticles has been made by developing methods such as co-precipitation, thermal decomposition and/or reduction, micelle synthesis, and hydrothermal synthesis. A major challenge still is protection against corrosion, and therefore suitable protection strategies will be emphasized, for example, surfactant/polymer coating, silica coating and carbon coating of magnetic nanoparticles or embedding them in a matrix/support. Properly protected magnetic nanoparticles can be used as building blocks for the fabrication of various functional systems, and their application in catalysis and biotechnology will be briefly reviewed. Finally, some future trends and perspectives in these research areas will be outlined.     

Green Synthesis and Applications of ZnO and TiO2 Nanostructures

Over the last two decades, oxide nanostructures have been continuously evaluated and used in many technological applications. The advancement of the controlled synthesis approach to design desired morphology is a fundamental key to the discipline of material science and nanotechnology. These nanostructures can be prepared via different physical and chemical methods; however, a green and ecofriendly synthesis approach is a promising way to produce these nanostructures with desired properties with less risk of hazardous chemicals. In this regard, ZnO and TiO₂ nanostructures are prominent candidates for various applications. Moreover, they are more efficient, non-toxic, and cost-effective. This review mainly focuses on the recent state-of-the-art advancements in the green synthesis approach for ZnO and TiO₂ nanostructures and their applications. The first section summarizes the green synthesis approach to synthesize ZnO and TiO₂ nanostructures via different routes such as solvothermal, hydrothermal, co-precipitation, and sol-gel using biological systems that are based on the principles of green chemistry. The second section demonstrates the application of ZnO and TiO₂ nanostructures. The review also discusses the problems and future perspectives of green synthesis methods and the related issues posed and overlooked by the scientific community on the green approach to nanostructure oxides.     

Strategies for the enantioselective synthesis of spirooxindoles

Oxindoles and spirooxindoles are important synthetic targets that are often considered to be prevalidated with respect to their biological activity and applications for pharmaceutical lead discovery. This review features efficient strategies for the enantioselective synthesis of spirocyclic oxindoles, focusing on reports in 2010 and 2011. Although enantioselective synthesis remains an ongoing challenge, exciting recent advances in this area feature spirooxindoles with greater complexity, up to eight stereogenic centers, more practical synthetic methods, and new catalytic activation strategies. Developments in catalyst systems and reaction conditions have shown that many reactions can be optimized to control selectivity and provide access to isomeric products, which are important for biological testing. This review is organized based on two primary disconnection strategies, and then further subdivided into the type and ring size of the spirocycle that is generated. Strategies are also compared for the synthesis of non-spirocyclic 3,3'-disubstituted oxindoles.     

Chemically specific coarse-graining of polymers: Methods and prospects

Coarse-grained (CG) modeling is an invaluable tool for the study of polymers and other soft matter systems due to the span of spatiotemporal scales that typify their physics and behavior. Given continuing advancements in experimental synthesis and characterization of such systems, there is ever greater need to leverage and expand CG capabilities to simulate diverse soft matter systems with chemical specificity. In this review, we discuss essential modeling techniques, bottom-up coarse-graining methodologies, and outstanding challenges for the chemically specific CG modeling of polymer-based systems. This methodologically oriented discussion is complemented by representative literature examples for polymer simulation; we also offer some advisory practical considerations that should be useful for new researchers. Given its growing importance in the modeling and polymer science community, we further highlight some recent applications of machine learning that enhance CG modeling strategies. Overall, this review provides comprehensive discussion of methods and prospects for the chemically specific coarse-graining of polymers.     

Gold catalysis in organic transformations: A review

This review updates the explosive development of gold catalysis for organic transformation focusing on the current literature over last 3 years. Recent investigations have shown that gold catalysis provides catalytically active systems, whereas selectivity and reusability are advantages over noncatalyzed organic transformations. The collected literature is focusing for new organic reactions and synthetic methodologies. Gold can also be suggested for green processes dedicated to fine chemicals, pharmaceuticals, and the food industry due to its recognized biocompatibility. The current review is focused on new methods in the organic synthesis that could be of interest in the wide area of organic chemistry for developing new catalytic pathways.     

A recent approach for the synthesis of 1,2,4-triazine systems bearing and/or containing phosphorus atoms as donor-acceptor interaction and their biocidal affects: An overview

Abstract

This review reports the developed methods for the synthesis of polyfunctional 1,2,4-triazine systems bearing and/or containing phosphorus atoms as donor-acceptors interactions. Most of the synthetic methods depend on the interaction between an amino group of the side chain of 1,2,4-triazine with phosphorus reagents. The biological activities, i.e. their biocidal affects as antioxidants, antimicrobials, anti-inflammatory as well as molluscicidal agents against some snails are discussed.     

唾液酸糖苷化方法学研究*

唾液酸是一类酸性九碳糖,通过α-糖苷键的方式广泛分布于生物体系内糖缀合物和多聚唾液酸中而发挥着重要的生物学功能。如何有效地构建唾液酸α-糖苷键,合成天然的含有唾液酸的糖缀合物、多聚唾液酸及其衍生物,是糖化学研究的热点和难点。近年来,人们基于唾液酸的结构特点,一方面通过在C2位引入易离去的基因,发展了直接成苷的方法,显著提高成苷的产率;另一方面,通过对C1和C3位引入辅助基因,发展了间接成苷的方法,提高了成苷的α-选择性。本文主要从直接成苷和间接成苷两个方面对目前研究的唾液酸糖苷化的化学方法学进行综述。     

De Novo Synthesis of Mono‐ and Oligosaccharides via Dihydropyran Intermediates

The importance of carbohydrates is evident by their essential role in all living systems. Their syntheses have attracted attention from chemists for over a century. Most chemical syntheses in this area focus on the preparation of carbohydrates from naturally occurring monosaccharides. De novo chemical synthesis of carbohydrates from feedstock starting materials has emerged as a complementary method for the preparation of diverse mono‐ and oligosaccharides. In this review, the history of de novo carbohydrate synthesis is briefly discussed and particular attention is given to methods that address the formation of glycosidic bonds for potential de novo synthesis of oligosaccharides. Almost all methods of this kind involve the formation of dihydropyran intermediates. Recent progress in forming dihydropyrans by Achmatowicz rearrangement, hetero‐Diels–Alder cycloaddition, ring‐closing metathesis, and other methods is also elaborated.