Green synthesis of triazolo-nucleoside conjugates via azide–alkyne C–N bond formation

Modified nucleosides are the core precursors for the synthesis of artificial nucleic acids, and are important in the field of synthetic and medicinal chemistry. In order to synthesize various triazolo-compounds, copper and ruthenium catalysed azide–alkyne 1,3-dipolar cycloaddition reactions also known as click reaction have emerged as a facile and efficient tool due to its simplicity and convenient conditions. Introduction of a triazole ring in nucleosides enhances their therapeutic value and various photophysical properties. This review primarily focuses on the plethora of synthetic methodologies being employed to synthesize sugar modified triazolyl nucleosides, their therapeutic importance and various other applications.

Recent Developments in the Synthesis of Bicyclic Condensed Pyrimidinones

Functionalized bicyclic pyrimidinones and their derivatives are significant heterocyclic scaffolds being their all-around prevalence in biologically potent compounds. In several attempts to explore the different synthetic methodologies for the construction of bicyclic condensed pyrimidinones, different researchers from all across the globe have reported numerous substantial methods. In the present review, considerable work has been critically compiled on the synthesis of substituted and functionalized bicyclic pyrimidinones from 2000 onwards.

14 Electrochemistry in Natural Product Synthesis

The multistep synthesis of natural products has historically served as a useful and informative platform for showcasing the best, state-of-the-art synthetic methodologies and technologies. Over the last several decades, electrochemistry has proved itself to be a useful tool for conducting redox reactions. This is primarily due to its unique ability to selectively apply any oxidizing or reducing potential to a sufficiently conductive reaction solution. Electrochemical redox reactions are readily scaled and can be more sustainable than competing strategies based on conventional redox reagents. In this chapter, we summarize the examples where electrochemistry has been used in the synthesis of natural products. The chapter is organized by the reaction type of the electrochemical step and covers both oxidative and reductive reaction modes.

Asymmetric hydrogenation and transfer hydrogenation in the enantioselective synthesis of flavonoids

Asymmetric hydrogenation (AH) and asymmetric transfer hydrogenation (ATH) are versatile synthetic methodologies widely employed in the preparation of chiral compounds. In this review, we explore the applications of AH and...

6′-O-Lactose Ester Surfactants as an Innovative Opportunity in the Pharmaceutical Field: From Synthetic Methods to Biological Applications

Glycolipid surfactants are biocompatible and biodegradable compounds characterized by potential applications in various sectors including pharmaceuticals, cosmetics, agriculture, and food production. A specific overview regarding synthetic methodologies and properties of 6′-lactose-based surfactants is presented herein, particularly all the synthetic approaches to this class of lactose esters, such as enzymatic and traditional organic syntheses. Moreover, detailed descriptions of physicochemical data and biocompatibility properties of these molecules, that is, surface tension, critical micelle concentration, emulsifying ability, foaming, particle size distribution, biocompatibility, and safety, are described. Biological applications with a focus on permeability enhancing, antimicrobial activity, and antibiofilm properties of 6′-lactose-based esters are also reported.

Confining the Inner Space of Strained Carbon Nanorings

Strained aromatic macrocycles based on cycloparaphenylenes (CPPs) are the shortest repeating units of armchair single-walled carbon nanotubes. Since the development of several new synthetic methodologies for accessing these structures, their properties have been extensively studied. Besides the fundamental interest in these novel molecular scaffolds, their application in the field of materials science is an ongoing topic of research. Most of the reported CPP-type macrocycles display strong binding toward fullerenes, due to the perfect match between the convex and concave π-surfaces of fullerenes and CPPs, respectively. Highly functionalized CPP derivatives capable of supramolecular binding with other molecules are rarely reported. The synthesis of highly functionalized [n]cyclo-2,7-pyrenylenes leads to CPP-type macrocycles with a defined cavity capable of binding non-fullerene guests with high association constants.

On the synthesis of a novel chiral phosphorodiamidic acid containing the α-phenylethyl moiety: Insights in its conformation and reactivity

A few years ago, the synthesis of chiral phosphoric acids supported on chiral BINOL frameworks was accomplished by T. Akiyama and M. Terada. Subsequent relevant applications demonstrated the importance of chiral phosphoric acids as privileged chiral inducers in asymmetric organocatalysis. In the present report we discuss the development of novel chiral phosphorodiamidic acids derived from C2-symmetric trans-1,2-diaminocyclohexane aliphatic frameworks. The preparation of the new chiral Brønsted acids, based on the intermediacy of a 1,3,2-diheterophospholan-2-oxide moiety, turned out to be challenging since several plausible synthetic methodologies proved to be ineffective. Furthermore, the five membered heterocyclic moiety turned out to be easily hydrolyzed when exposed to nucleophilic alcohols or water. Complementary to the successful multistep synthesis reported here, it was possible to obtain crystals of the key precursor of the desired phosphorodiamidic acid, which proved suitable for X-ray diffraction analysis and hence to establish important conformational characteristics of the novel heterocycle.

1,4-Azaborines: Origin, Modern Synthesis, and Applications as Optoelectronic Materials

This short review summarizes the origins and recent progress in 1,4-azaborine research, focusing on synthetic methodologies. Academic laboratories have made significant efforts to generate boron-nitrogen-containing heteroaromatic compounds that mimic arenes. 1,2-, 1,3-, and 1,4-Azaborine motifs have provided breakthrough molecules in applications ranging from medicines to materials. Owing to recent advances in polyaromatic 1,4-azaborine synthesis and applications in industry, the research field is currently undergoing a renaissance. Photo- and electroluminescent properties driven by distinct structural variations are key components in the design of novel 1,4-azaborine structures. In this review, seminal reports on the synthesis of simple 1,4-azaborines to complex π-extended structures are briefly highlighted together along with key optoelectronic properties.1 Introduction2 Non-Fused 1,4-Azaborines3 Monobenzo-Fused 1,4-Azaborines4 Dibenzo-Fused 1,4-Azaborines and Their Derivatives5 Ladder-Type 1,4-Azaborines6 Complex 1,4-Azaborines7 Optoelectronic Properties of Key 1,4-Azaborines8 Conclusion and Outlook

Bioinspired Metal Nanoparticles for Microbicidal Activity

The broad reception for nanotechnology is due to their appreciable size and versatile applications in the interdisciplinary areas. In this modern era one of the major problems is microorganisms possessing antibiotic resistance, nanoparticles (NPs) are a lucrative option to solve this. In materials science, “green synthesis” has gained extensive attention as a reliable, sustainable, and eco-friendly protocol for synthesizing a wide range of materials, especially metals, and metal oxides nanomaterials, hybrid materials and bioinspired materials. As such, green synthesis is regarded as an important tool to reduce the destructive effects associated with the traditional methods for synthesis of nanoparticles commonly utilized in laboratory and industry. Bio-inspired NPs held edges over conventionally synthesized nanoparticles due to their low cost, easy synthesis and low toxicity. This chapter elaborates the developments on the biosynthesis of NPs using natural extracts with particular emphasis on their application as microbiocidal agents. This chapter has very specifically dealt with coinage metals such as Cu, Ag, Au due to their significance of antimicrobial activities. Succeeding, reported the developments in the synthetic methodologies of metal-oxide (Titanium dioxide, TiO2) nanoparticles using novel plant extracts with high medicinal value and their corresponding ability to degrade bacterial pathogens through advanced oxidation process (AOPs) based on heterogeneous photocatalysis.