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[Display omitted] Morpholines are widespread in many biologically and catalytically active agents, thus being an important aim of pharmaceutical and synthetic chemists. However, efficient strategies for the catalytic asymmetric synthesis of chiral morpholines bearing crowded stereogenic centers still remain elusive. Herein, we disclose a Cu-catalyzed asymmetric propargylic amination/desymmetrization strategy to help resolve this challenge. As a result, two kinds of structurally various chiral morpholines bearing rich functional groups and N -α-quaternary stereocenters were produced with high efficiency and selectivity (42 examples, up to 91% yield, 97:3 er and > 19:1 dr). In addition, a series of transformations were performed to demonstrate the synthetic utility of this methodology. In particular, a hit compound for new antitumor drugs was identified through cellular evaluation. Furthermore, mechanistic investigations reveal that, hydrogen bonding in the key copper-allenylidene intermediate together with π-π stacking aids remote enantioinduction. [ABSTRACT FROM AUTHOR]

With the rise of machine learning (ML), the modeling of chemical systems has reached a new era and has the potential to revolutionize how we understand and predict chemical reactions. Here, we probe the historic dependence on utilizing enantiomeric excess (ee) as a target variable and discuss the benefits of using relative Gibbs free activation energies (ΔΔG≠), grounded firmly in transition‐state theory, emphasizing practical benefits for chemists. This perspective is intended to discuss best practices that enhance modeling efforts especially for chemists with an experimental background in asymmetric catalysis that wish to explore modelling of their data. We outline the enhanced modeling performance using ΔΔG≠, escaping physical limitations, addressing temperature effects, managing non‐linear error propagation, adjusting for data distributions and how to deal with unphysical predictions,in order to streamline modeling for the practical chemist and provide simple guidelines to strong statistical tools. For this endeavor, we gathered ten datasets from the literature covering very different reaction types. We evaluated the datasets using fingerprint‐, descriptor‐, and graph neural network‐based models. Our results highlight the distinction in performance among varying model complexities with respect to the target representation, emphasizing practical benefits for chemists. [ABSTRACT FROM AUTHOR]

Many of the functions and features of practically useful materials are the province of molecular‐level chemistry and their modulation at different length‐scale. This report illustrates the molecular‐level chemistry behind functions and features of the [2.2]paracyclophane‐based materials with a particular focus on the most recent explorations on through‐space conjugated small‐molecule organic emitters, π‐stacked macrocyclic molecules and polymers, poly(p‐phenylenevinylene)s featuring well‐defined donor‐acceptors sequence control, and surface engineering of technologically‐relevant parylenes that finds broad applications across the field of chemical science and technology. This report largely deals with the potential and opportunities associated with molecular features and functions of planar chirality, conformational behaviors, strain‐induced non‐planarity of the aromatics, the profound impacts of through‐space conjugation and π‐electron interactions/delocalization on optoelectronic properties of the π‐conjugated organic emitters, polymers and extended structures consisting of cyclophanes. A special focus is put on the concept of supramolecular polymers using chemically‐programmed chiral cyclophanes via non‐covalent stacking and controlled conformational arrangements. Illustrating cyclophane as precursors/monomers and fabrication strategies for their incorporation in structurally‐controlled (poly(p‐xylylene)s formed via chemical vapor deposition polymerization and post‐deposition fabrication for interface engineering is described. Demonstrating a rather different approach of electronically‐dictated ring‐opening metathesis polymerization employing strained cyclophane‐diene precursors that generate conjugated poly(p‐phenylenevinylene)s with well‐defined (i.e., low dispersity) and donor‐acceptor sequence control is also discussed. This report will serve as an indispensable one‐stop reference for organic, and polymer chemists, as well as material scientists working with cyclophanes for research innovations. [ABSTRACT FROM AUTHOR]

Reticular chemistry has In the post-synthetic modification (PSM) of frameworks one of the most versatile tools to adapt the systems' physicochemical properties to the specific requirements which are imposed by their application in different contexts. We can safely say that PSM methodologies in all their variants are currently one of the main resources that reticular chemists turn to when they need to diversify a framework compositionally. Practically all these modifications require the integration of functional groups appended to the organic linkers in the framework, either by direct synthesis or by post-synthetic exchange. The reactivity of these tags allows, at a subsequent stage, covalent modification of the framework under conditions that ideally respect its structural integrity. In this perspective article we introduce the use of tetrazine-based linkers as intrinsically tagged alternatives to integrate PSM with click chemistry reactivity. This strategy is ideally suited to molecular frameworks, as it combines very mild modification conditions with direct control over the organisation of built-in appendices and the acknowledged potential of click chemistry to build framework libraries. [ABSTRACT FROM AUTHOR]

An efficient redox-neutral palladium-catalyzed system has been developed to introduce indole and pyrrole units to a wide range of bioactive molecules via late-stage aryl C–H activation, providing a robust tool for medicinal chemists to explore structure–activity relationships (SARs). Furthermore, the successful gram-scale reaction and subsequent synthetic investigations demonstrate the potential application of this established method in organic synthesis, materials science, and biochemistry. [ABSTRACT FROM AUTHOR]

Accurately synthesizing coordination‐driven metal‐organic cages with customized shape and cavity remains a great challenge for chemists. In this work, a bottom‐up step‐wise coordination‐driven self‐assembly approach was put forward. Employing this strategy, three terpyridyl heterometallic‐organic truncated tetrahedral cages with different sizes and cavity were precisely synthesized. Firstly, the coordination of tripodal organic ligands with Ru2+ afforded dendritic metal‐organic ligands L1‐L3. Then the Ru building blocks complexed with Fe2+ and shrunk to form the desired heterometallic‐organic cages (C1‐C3). These discrete heterometallic‐organic supramolecular cages were fully characterized and displayed the large and open cavities varied from 7205 Å3 to 9384 Å3. Notably, these cages could not be directly constructed by single‐step assembly process using initial organic ligands or dimeric metal‐organic ligands, indicative of the irreplaceability of a bottom‐up step‐wise assembly strategy for size‐customized architectures. This work paves a new way for precisely constructing metal‐organic cages with well‐defined cavities. [ABSTRACT FROM AUTHOR]

Axially chiral furan‐based scaffolds have been recognized as a class of important five‐membered heteroaryl atropisomers, and developing catalytic atroposelective reactions for constructing this class of scaffolds is highly desirable. However, the catalytic atroposelective construction of such scaffolds is rather underdeveloped due to the existence of great challenges such as remote ortho‐substituents and weak configurational stability. To overcome these challenges, synthetic chemists have recently paid great attention to this research field, and a number of axially chiral furan‐based scaffolds have been constructed via catalytic atroposelective reactions using different strategies. This concept summarized these advances in this field and pointed out the remaining challenges, which will promote the further development of this emerging field. [ABSTRACT FROM AUTHOR]

Motivated by her interest in fabric arts, late-eighteenth-century British chemist Elizabeth Fulhame experimentally investigated whether cloths of gold, silver, and other metals could be made by chemical rather than mechanical processes. In contrast to other women studying science at this time, she not only published an original monograph under her own name that challenged both the phlogistic and antiphlogistic views of combustion but also proposed an alternative explanation for oxidation and reduction. Although her contemporaries widely cited her innovative research, her history is not well known, yet a careful analysis of her work provides further insights into the reception of the antiphlogistic theory and the challenges and limitations experienced by women in chemistry during this period. [ABSTRACT FROM AUTHOR]

Stemming from early seminal notions of molecular recognition and encapsulation, three-dimensional, cavity-containing capsular compounds and assemblies have attracted intense interest due to the ability to modulate chemical and physical properties of species encapsulated within these confined spaces compared to bulk environments. With such a diverse range of covalent motifs and non-covalent (supramolecular) interactions available to assemble building blocks, an incredibly wide-range of capsular-type architectures have been developed. Furthermore, synthetic tunability of the internal environments gives chemists the opportunity to engineer systems for uses in sensing, sequestration, catalysis and transport of molecules, just to name a few. In this tutorial review, an overview is provided into the design principles, synthesis, characterisation, structural facets and properties of coordination cages, porous organic cages, supramolecular capsules, foldamers and mechanically interlocked molecules. Using seminal and recent examples, the advantages and limitations of each system are explored, highlighting their application in various tasks and functions. [ABSTRACT FROM AUTHOR]

Utilizing electrons directly offers significant potential for advancing organic synthesis by facilitating novel reactivity and enhancing selectivity under mild conditions. As a result, an increasing number of organic chemists are exploring electrosynthesis. However, the efficacy of electrochemical transformations depends critically on the design of the electrochemical cell. Batch cells often suffer from limitations such as large inter-electrode distances and poor mass transfer, making flow cells a promising alternative. Implementing flow cells, however, requires a foundational understanding of microreactor technology. In this review, we briefly outline the applications of flow electrosynthesis before providing a comprehensive examination of existing flow reactor technologies. Our goal is to equip organic chemists with the insights needed to tailor their electrochemical flow cells to meet specific reactivity requirements effectively. We also highlight the application of reactor designs in scaling up electrochemical processes and integrating high-throughput experimentation and automation. These advancements not only enhance the potential of flow electrosynthesis for the synthetic community but also hold promise for both academia and industry. [ABSTRACT FROM AUTHOR]

The optically active lactams represent an important structural motif and present in a wide range of natural products, biologically active compounds and drugs. Compared to the synthesis of chiral five‐ and six‐membered lactams, the asymmetric construction of seven‐membered lactams often presents a challenge due to their consequential entropic and enthalpic barriers. Over the past few decades, substantial efforts have been devoted to this field and chemists have developed various efficient strategies for the preparation of seven‐membered lactams. In this review, we will highlight the recent advances in enantioselective formation of seven‐membered lactams and the discussion will be logically divided into three parts according to the reaction mode. The aim of this review is to familiarize the Reader with new synthetic opportunities offered by these interesting methodologies. [ABSTRACT FROM AUTHOR]

AbstractAmong the most prominent realizations of Morris J. Robins in the antiviral nucleoside chemistry are (i) the synthesis of 8-substituted (methyl-, amino-, bromo-, iodo) derivatives of acyclovir, (ii) xylotubercidin as an inhibitor of herpes simplex virus (HSV) infections, (iii) the anti-HIV activity of the 2’,3’-dideoxyriboside of 2,6-diaminopurine (ddDAPR) and the 3’-azido- and 3’-fluoro derivatives thereof (AzddDAPR and FddDAPR, respectively), (iv) the potentiating effect of ribavirin on the anti-HIV activity of 2’,3’-dideoxyinosine (ddI) and ddDAPR, (v) S-adenosylhomocysteine hydrolase (SAH) inhibitors principally active against vaccinia virus (VV) and vesicular stomatitis virus (VSV), and (vi) furo[2,3-d]pyrimidinone derivatives active against varicella-zoster virus (VZV). [ABSTRACT FROM AUTHOR]

Ever since its invention, mass spectrometry has been seen as a remedy for all of the riddle that an analytical chemist was ever called to answer. Indeed, a good mass expert, provided with a good instrument and an updated library, would be able to answer to the question "what is it?" or "what does it have inside?". In most of the cases, nevertheless, there is sometimes the need of using other type of techniques in order to avoid misunderstandings and wrong interpretations of the results. Therefore, the aim of this work is to compare real forensic cases where mass spectrometry played a fundamental role to obtain tangible and trustable answers, to other ones where this technique proved to be totally misleading. Those that will be shown, are real, concrete cases – slightly modified in order to make them unrecognisable. [ABSTRACT FROM AUTHOR]

Developing multicomponent reactions in a cascade manner is a long-standing interest to chemists to access valuable organic materials more economically. Herein, we described a simple, economically viable method for synthesizing 11H-benzo[b]fluoren-11-one, a dual-state organic fluorophore, starting from ortho phthalaldehyde (OPA) in DMSO solvent. Simple and rapid product isolation, high atom economy, short reaction time, and scalability are the attractive features of the method. During the optimization of the reaction condition, we observed that DMSO, DMF, and acetone served one carbon to form the said compound besides their role as solvents. A plausible mechanism has been proposed based on the evidence obtained from LCMS analysis of the incomplete reaction mixture. [ABSTRACT FROM AUTHOR]

• Lasso peptides are diverse macrolactam-containing ribosomal peptide natural products distinguished by a kinetically trapped [1]rotaxane fold. • While leader peptidolysis is reasonably well understood, comparatively little is known about how lasso cyclases tie their substrates into the characteristic lariat knot. • Genome mining has enabled the accurate prediction of thousands of lasso peptides. Coupled with new expression methods, it has dramatically expanded our understanding of their diversification potential. • While some lasso peptides have established biological activities, most have elusive functions. Collaboration between natural product chemists, specialists in omics, and microbiologists will be essential to diversify bioactivity screens and understand the role of lasso peptides in the environment. Lasso peptides are a large and sequence-diverse class of ribosomally synthesized and post-translationally modified peptide (RiPP) natural products characterized by their slip knot-like shape. These unique, highly stable peptides are produced by bacteria for various purposes. Their stability and sequence diversity make them a potentially useful scaffold for biomedically relevant folded peptides. However, many questions remain about lasso peptide biosynthesis, ecological function, and diversification potential for biomedical and agricultural applications. This review discusses new insights and open questions about lasso peptide biosynthesis and biological function. The role that genome mining has played in the development of new methodologies for discovering and diversifying lasso peptides is also discussed. [ABSTRACT FROM AUTHOR]

The synthesis and isolation of a bismuth‐based analogue of the venerable triphenylphosphine oxide (Ph3PO) has remained a chimera to synthetic chemists for many years, due to its predicted high reactivity and instability. Through the hydrolysis of a cationic fluorotriarylbismuthonium(V) salt, we report here the isolation of unique hydroxytriarylbismuth(V) complexes, which served as precursor for the formation of the elusive monomeric triarylbismuthine oxide Dipp3Bi=O. Combined spectroscopic, crystallographic and computational studies provided insight into the bonding situation of the first monomeric triorganobismuth oxide complex. The Dipp3Bi=O and Mes3BiO⋅LiBArF complex exhibits O‐atom transfer reactivity, an uncommon reactivity feature for Ar3Pn=O. [ABSTRACT FROM AUTHOR]

Evolutionary selection in nature has led to hierarchical structuring as a fundamental optimization strategy for biological structures, maximizing functional performance while minimizing resource usage. Precise hierarchical organization of natural materials over a wide range of length scales gives rise to unique synergistic properties that could not be achieved by single components. Despite the clear advantages offered by hierarchically structuring matter, mastering hierarchical control based on the current synthetic toolbox is still a challenge. In this review, some recent advancements in the fabrication of hierarchical metal organic framework (MOF) materials are highlighted and the advantages that arise due to different kinds of MOF hierarchy are critically analyzed. The special focus of the review lies in highlighting the applications where MOF hierarchical materials can be most impactful and describing characterization techniques currently at the disposal of scientists for the precise characterization of MOF hierarchical structures across all length scales. Finally, the intent is to inspire reticular chemists to master hierarchical control of MOF materials so as to fully utilize the advantages MOFs offer for various applications. [ABSTRACT FROM AUTHOR]

Macrolactonization is a challenging process where high dilution and temperatures can extend reaction times and promote reagent degradation. Biocatalysis is a versatile strategy for synthesis but not traditionally associated within the toolbox of organic chemists for macrocyclization. Macrolactonization has been investigated using modern methods employing both catalysis and stoichiometric activation strategies on 20 different substrates with differing ring sizes and types (cyclophanes, macrolactones, macrodiolides) and structural features at the reaction site (central vs. planar chirality; primary vs. secondary alcohols). The data demonstrates that of all protocols examined, the biocatalytic route was superior, providing the highest average yields across all classes of macrocycles studied. From the stoichiometric activation strategies investigated, the Yamaguchi macrolactonization was the most versatile in terms of ring size and nature. Despite the advantages of biocatalytic macrolactonization, advances in developing supported, versatile non-enantioselective lipases would actually represent a useful tool in molecular synthesis. [ABSTRACT FROM AUTHOR]

Past decades have witnessed significant advance of isocyanides as a class of versatile organic synthons as well as their broad applications in multi-component reactions (MCRs) and other tandem reactions. Reactions involving multiple isocyanides allow the construction of molecules with further diversification and complexity, while C–H functionalization emphasizes the advantages of high atom economy, broad substrate availability and great synthetic efficiency. This promising synergistic strategy of C–H functionalization involving multiple isocyanides provides a variety of valuable synthetic methods for organic chemists' toolbox and offers considerable potential in pharmaceutical chemistry and materials science as well. The present review outlines in detail various reaction types of C–H functionalization enabled by multiple isocyanides, and the relevant mechanistic rationale is discussed. [ABSTRACT FROM AUTHOR]

Expanding on his study of the social construction of technology, Bijker used a technological frame to explain the factors involved in the success development of Bakelite. It is generally accepted that the successful synthesis of Bakelite was particularly helped by the fact that the inventor, Baekeland, was more deeply included in the technological frame of electrochemical engineers rather than that of celluloid chemists. However, a careful reading of Bijker's case study reveals that (i) the technological frame contributing to the synthesis of Bakelite is separate from the technological frame of electrochemical engineers and (ii) it was formed by collecting components of the technological frame (called technological frame parts in this paper) of the community to which Baekeland belonged and in which he was included as well as the technological frames of celluloid chemists and electrochemical engineers. [ABSTRACT FROM AUTHOR]

Oxazole, a five‐membered cyclic ring containing oxygen and nitrogen, displays diverse interactions and structural variations, enhancing its potential applications across various domains. Oxazole derivatives exhibit diverse pharmacological activities, including antidiabetic, anticonvulsant, anticancer, phosphodiesterase inhibition, antiprotozoal, and antibacterial effects, making them appealing to medicinal chemists. Their presence in naturally occurring pharmacologically active substances as well as synthetic medicines underscores their therapeutic potential. This review encompasses recent advancements in the biological activities of oxazole derivatives during the period of 2018–2023. The discussed activities include antitumor, central nervous system (CNS) modulation, antidiabetic, anti‐Alzheimer, antibacterial, and enzyme inhibitory effects. The review highlights the mechanisms of action of these compounds in various diseases, the most potent compounds along with their respective IC50/MIC (inhibitory concentration/minimum inhibitory concentration) values, and discusses the models utilized for quantifying their activity. Currently, there are eight FDA‐approved drugs bearing oxazole scaffolds available in the market. Analysis of the literature reveals that the antitumor activity of oxazole derivatives is particularly noteworthy among their various activities. The incorporation of phenyl, methoxyphenyl, or halogen‐substituted phenyl moieties significantly enhances therapeutic activities compared to reference drugs. The substitution flexibility at three positions of oxazole derivatives contributes to their spectrum of pharmacological activities. [ABSTRACT FROM AUTHOR]

AbstractSince no later than the 1970s, organic chemists have speculated on the role of glycosyl oxonium ions in chemical O-glycosylation. Such species result from the attack of ethers on glycosyl oxocarbenium ions and are invoked to explain 1,2-cis-selectivity in ether solvents. However, a systematic study to probe this phenomenon appears to be lacking in the chemical literature. Herein, we study the effects of solvent, counteranion, protecting group electron-withdrawing effects, and acceptor on O-glycosylation stereoselectivity with D-glucosyl trichloroacetimidate donors. While many of these transformations proceed with 1,2-cis-selectivity, our results suggest that glycosyl oxonium ions play minimal, if any, role in O-glycosylation. [ABSTRACT FROM AUTHOR]

Comprehensive Summary The pursuit of sustainable and environmentally benign synthetic methods continues to challenge organic chemists. Herein, we introduce a magnetoredox system for tri‐ and difluoromethylation of isocyanides and N‐arylacrylamides using a rotating magnetic field and steel rods. This magnetoredox approach enables facile synthesis of functionalized phenanthridines and oxindoles without the need for catalysts and additives under mild conditions. Such a system potentially represents an attractive strategy for selective formation of bonds through multifaceted regulation of magnetic intensity, rotating frequency, and rod size. [ABSTRACT FROM AUTHOR]

Chiral amine scaffolds are among the most important building blocks in natural products, drug molecules, and functional materials, which have prompted chemists to focus more on their synthesis. Among the accomplishments in chiral amine synthesis, transition-metal-catalyzed enantioselective C–N cross-coupling is considered one of the most efficient protocols. This approach combines traditional C(sp2)–N cross-coupling methods (such as the Buchwald–Hartwig reaction Ullmann-type reaction, and Chan–Evans–Lam reaction), aryliodonium salt chemistry and radical chemistry, providing an attractive pathway to a wide range of structurally diverse chiral amines with high enantioselectivity. This review summarizes the established protocols and offers a comprehensive outlook on the promising enantioselective C–N cross-coupling reaction. [ABSTRACT FROM AUTHOR]

Nile Tilapia (Oreochromis niloticus) is the most widely cultivated freshwater fish because it can grow well in tropical countries and temperate regions. This research aims to create artificial feed that matches the nutritional parameters needed by nile tilapia. This artificial feed will use the basic ingredients of shrimp waste, with addition of oilcake, bran, starch flour, vitamins, squid oil, and water. There are four variables used to make artificial feed with different basic and additional ingredients, as well as varied processing techniques. After artificial feed is completed, proximate analysis will be carried out to test composition of crude fiber, carbohydrates, water, fat, ash, and protein using various methods. The test method for the composition of crude fiber, carbohydrates, fat, ash, and protein follows the method set by the Association of Official Analytical Chemists (AOAC). Based on the results of proximate analysis, variable 1 (V1) has fulfilled the nutritional content of protein and moisture content needed by nile tilapia. This shows that artificial feed formulations from shrimp waste can be used because protein is an important element for nile tilapia growth, but the content of crude fiber, carbohydrates, fat, and ash exceeds ideal value for nile tilapia nutrition. This also occurs in variables 2, 3, and 4 that have not met nutritional needs, especially protein. However, the composition of artificial feed with shrimp waste and addition of meal, bran, starch flour, vitamins, and water in V1 can be further investigated to reduce the content of crude fiber, carbohydrates, fat, and ash. [ABSTRACT FROM AUTHOR]

Pyrimidine is a moiety that occurs in living organisms and has a variety of significant biological properties in pharmacology. Due to the easy handling of synthesis, easily available precursor, and less duration for the reaction, for the synthesis, not many technical skills are needed. All these factors attract chemists to focus more on pyrimidines. Apart from the synthesis of biological applications of pyrimidines, medicinal chemists have gathered to explore more pyrimidine scaffolds due to their interesting medicinal properties and easy targeting of various binding sites. This review delves into the diverse biological activities of compounds derived from pyrimidine during the year 2024. We have attempted to explore the growing significance of pyrimidine derivatives and provide a new path for designing new potent molecules. [ABSTRACT FROM AUTHOR]

Dihydropyrimidinone skeleton (DHMP) plays a vital part in medicinal and pharmaceutical chemistry as its derivatives exhibit a broad spectrum of anti-microbial, anti-fungal, anti-bacterial, anti-inflammatory and anti-cancer activities. Taking into account the biological significance of DHPMs, organic chemists have developed different methodologies to synthesize these biologically active target molecules. Our review focuses on the one-pot synthesis of dihydropyrimidinones via Biginelli reaction by using the efficient catalysts and reaction conditions, thereby covering the literature published since 2021. [ABSTRACT FROM AUTHOR]

Angucyclines and angucyclinones represent a class of natural compounds that belong to the group of aromatic polyketides. They exhibit a wide array of biological properties, such as antimicrobial, antiviral, and cytotoxic. Their considerable therapeutic potential and diverse scaffolds have attracted many synthetic chemists to devise novel strategies to construct their intricate molecular architecture. Over 300 class members have been isolated from natural sources, mainly from bacterial strains of Streptomyces species. This review highlights recent advancements in their synthesis, such as oxidative cyclization, photooxidation, and metal‐catalyzed [4+2]‐cycloaddition, which has facilitated the efficient and practical total syntheses of various angucycline and angucyclinone natural products. [ABSTRACT FROM AUTHOR]

Context: Proximate analysis is also called the Weende method. It has been the standard used for describing the chemical composition of feed ingredients for the past 150+ years. Understanding of the chemical composition of feeds has changed greatly in that time. Most of the current terms used for proximate analyses are unclear and misleading: (1) Crude protein , nitrogen × 6.25 describes true protein plus any other nitrogen-containing compounds including nucleotides and even phospholipids. (2) Crude fibre represents approximately half of the true fibre in most ingredients, but only approximately one-seventh of the fibre in important ingredients like soybean meal. (3) Ether Extract represents the neutral lipids in ingredients but little of the polar lipids like the lecithins. (4) The Nitrogen-free Extract is not an extract at all. It is supposed to represent starch in feed, but it contains large proportions of pectin, hemicellulose and even some cellulose. It reflects the error in Crude Fibre. Inadequacies of the Weende system have been known for a very long time. Animal producers desire to embrace modern technology and adapt more precise feeding techniques. Aims: This paper explains how 19th century chemistry relates to 21st century understandings of feed composition and proposes an updated method of feed ingredient analysis. Methods: A new method of describing feed composition based on 13 modern chemical categories was conceived and called the 'Armidale Method', to distinguish it from the Weende method. The new feed chemical category method was used to compile a preliminary database based on: moisture, sugars, oligosaccharides, starch, pectin, hemicellulose, cellulose, lignin, ash, neutral lipids, polar lipids, true protein, and nonprotein nitrogenous compounds. Key results: Composition values for 26 ingredients compiled from three sources averaged 1032.0 ± 49.5 g/kg, comparable to the theoretical 1000 g/kg. Conclusions: The Armidale Method of analyses could be the starting point for discussions of new standardised procedures for ingredient trade and feed formulation. Implications: It is time for producers, in conjunction with nutritionists and analytical chemists, to explore the best ways to represent the composition of feed ingredients for feeding value and trade. Since the 19th century, when little was known about chemical composition of feeds, gross feed analysis for trade and estimating energetic contributions has been based on the Weende method (moisture, crude protein, crude fibre, ether extract, ash and nitrogen-free extract). A new, Armidale Method, is proposed here. It consists of 13 chemical categories based on modern knowledge of feed chemistry (moisture, true protein, nonprotein nitrogenous compounds, neutral and polar lipids, sugars, oligosaccharides, starch, pectin, lignin, hemicellulose, cellulose, and ash). This paper belongs to Animal Science Reflections and Collection: Recent Advances in Animal Nutrition - Australia 2025. [ABSTRACT FROM AUTHOR]

Benzene is one of the most ubiquitous structural motifs in chemistry. The valence isomers of benzene have also attracted synthetic chemists' attention due to their unique structures, bonding, and reactivity. We have been investigating boron‐nitrogen‐containing benzene valence isomers via photoisomerization of 1,2‐azaborines. In this contribution, we summarize recent developments of these highly strained BN‐heterocyclic compounds including their synthesis, characterization, proposed mechanism of formation, and their potential applications. [ABSTRACT FROM AUTHOR]

A gradual increase in the development of novel, mild, and highly proficient strategies for the synthesis of medicinally and synthetically important organic scaffolds remains a prominent goal in synthetic chemistry. Since the last decade, researchers and chemists have been paying attention to developing visible light-catalyzed organic transformations, this review focuses on green methodologies, particularly on the involvement of light for efficacious synthesis. Visible light has been utilized for asymmetric synthesis, multi-component reactions, aerobic oxidation, superoxide generation, synthesis of spiro moieties, stereoselective synthesis, etc. The advantages and boundaries of visible light in organic transformations have been well demonstrated, along with several representative examples. [ABSTRACT FROM AUTHOR]

While the supramolecular chemistry of simple anions is ubiquitous, the targeting and exploitation of their metal‐containing relatives, the metalates, is less well understood. This mini review highlights the latest advances in this emergent area by discussing the supramolecular chemistry of metalates thematically, with a focus on the exploitation of metalates in a diversity of applications, including medical imaging and therapy, environmental remediation, molecular magnetism, catalysis, perovskite materials, and metal separations. The unifying features of these systems are identified with a view to allow the supramolecular chemist to target the unique material properties of the metalates, even in areas that are currently relatively immature. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: The 21st century has witnessed a continuous evolution in the development of boron‐stereogenic chemistry. Since the 1990s, various innovations for the synthesis of tetracoordinate boron‐stereogenic compounds, which exhibited great potential applications, have been demonstrated by synthetic chemists. This paper reviews the significant progress and recent advances towards the assembly of enantioenriched boron‐stereogenic compounds, and hopes to shed light on new perspectives and inspire further research in this emerging field. [ABSTRACT FROM AUTHOR]

The chemistry of heterometallic metal complexes continues to attract the interest of molecular inorganic chemists mainly because of the properties that different metal ions can bring to compounds. Contrary to the plethora of 3d–4f- and 3d–3d′-metal complexes, complexes containing both 3d- and 4d-metal ions are much less studied. The choice of the bridging organic ligand is of paramount importance for the synthesis of such species. In the present work, we describe the use of the potentially tetradentate NOO′O″ Schiff bases N-(2-carboxyphenyl)salicylideneimine (saphHCOOH) and N-(4-chloro-carboxyphenyl)salicylideneimine (4ClsaphHCOOH) in CdII-MIII (M = Fe, Cr) chemistry. The complexes [Cd2Fe2(saphCOO)4(NO3)2(H2O)2] (1), [Cd2Cr2(saphCOO)4(NO3)2(H2O)2] (2), [Cd2Fe2(4ClsaphCOO)4(NO3)2(H2O)2] (3) and [CdCr2(4ClsaphCOO)4(H2O)3(EtOH)] (4) have been structurally characterized, the quality of the structure of the latter being poor but, permitting the knowledge of the connectivity and the main structural features. Complexes 1–3 are isostructural, but not isomorphous, possessing a variety of lattice solvent molecules (EtOH, MeCN, CH2Cl2, H2O). The metal topology can be described as two isosceles triangles sharing a common CdII...CdII edge. The two CdII atoms are doubly bridged by two μ-aqua groups. The MIII...CdII sides of the triangles are each asymmetrically bridged by one carboxylate oxygen atom of a 2.2111 saphCOO2−/4ClsaphCOO2− ligand. The core of the molecules is {Cd2M2(μ-Oaqua)2(μ-OR)4}6+, where the OR oxygen atoms are the bridging carboxylate oxygens. The coordination spheres of the metal ions in the centrosymmetric molecules are [Cd(Oaqua)2(Ocarboxylato)4(Onitrato)2] and [M(Nimino)2(Ocarboxylato)2(Ophenolato)2]. The biaugmented trigonal prism is the most appropriate for the description of the coordination geometry of the CdII atoms in 1 and 3, while the geometry of these metal ions in 2 is best described as distorted triangular dodecahedral. A combination of H-bonding and π–π stacking interactions give interesting supramolecular patterns in the three tetranuclear compounds. The three metal ions in 4 define an isosceles triangle with two almost equal CdII...CrIII sides. The CdII center is linked to each CrIII atom through one carboxylato oxygen of a 2.2111 4ClsaphCOO2− ligand. The core of the molecule is {CdCr2(μ-OR)2}6+, where the OR oxygen atoms are the bridging carboxylato oxygens. A tridentate chelating 1.1101 4ClsaphCOO2− ligand is bonded to each CrIII. The coordination spheres are [Cd(Oaqua)3(Oethanol)(Obridging carboxylato)2(Oterminal carboxylate)2] and [Cr(Obridging carboxylato)(Oterminal carboxylato)(Ophenolato)2(Nimino)2]. Complexes 1–4 are the first heterometallic 3d–4d complexes based on saphHCOOH and 4ClsaphCOOH. The structures are critically compared with those of previous reported ZnII-MIII (M = Fe, Cr) complexes. The IR and Raman spectra of the complexes are discussed in terms of the coordination modes of the ligands involved. UV/VIS spectra in CH2Cl2 are also reported, and the bands are assigned to the corresponding transitions. The δ and ΔEQ57Fe-Mössbauer parameters of 1 and 3 at room temperature and 80 K suggest the presence of isolated high-spin FeIII centers. Variable-temperature (1.8–310 K) and variable-field (0–50 kOe) magnetic studies for 1 and 2 indicate the absence of MIII...MIII exchange interactions, in agreement with the long distances (~8 Å) between the paramagnetic metal ions. The combined work demonstrates the ability of saphCOO2− and 4ClsaphCOO2− to give 3d–4d metal complexes. [ABSTRACT FROM AUTHOR]

In recent years, Morita‐Baylis‐Hillman (MBH) carbonates have been extensively used in domino reactions for the synthesis of novel cyclic and acyclic compounds. This review highlights the progress made in the last decade in the synthesis of a series of compounds from an uncyclized reaction or annulation of MBH carbonates, which demonstrates that the excellent reactivity and high research value of MBH carbonates as representative substrates in organic synthesis. We hope the summary and understanding of the reactivity of MBH carbonates can inspire chemists to apply these substrates in the design of more efficient domino reactions, which will be beneficial for the organic synthesis and drug chemistry. [ABSTRACT FROM AUTHOR]

The 2024 Lasker~DeBakey Clinical Medical Research Award has been given to Joel Habener and Svetlana Mojsov for their discovery of a new hormone GLP-1(7-37) and to Lotte Knudsen for her role in developing sustained acting versions of this hormone as a treatment for obesity. Each of the three had a distinct set of skills that made this advance possible; Habener is an endocrinologist and molecular biologist, Mojsov is a peptide chemist, and Knudsen is a pharmaceutical scientist. Their collective efforts have done what few thought possible--the development of highly effective medicines for reducing weight. Their research has also solved a mystery that began more than a century ago. [ABSTRACT FROM AUTHOR]

The topological index is just one of several very useful tools that graph theory has made available to chemists. Topological indices are invariants of real numbers under graph isomorphisms. Several topological indices have been defined. Some of them are used to model chemical, pharmaceutical and other properties of molecules. The eccentric connectivity index (eci) is also a topological index. The eci of G, denoted by 휀c(G), is defined as 휀c(G) =∑ v∈V (G)deg(v)e(v), where deg(v) represents the degree of a vertex v and e(v) is its eccentricity. In this paper, exact formula for the eci of complementary prisms is derived. [ABSTRACT FROM AUTHOR]

3‐Methylpyridine holds a pivotal role in organic chemistry as it constitutes a fundamental structure in numerous biologically active compounds. Its significance is underscored by its involvement in synthesizing vitamin B3 and developing pyridine insecticides, garnering considerable attention. Consequently, chemists have dedicated efforts to devising efficient and environmentally friendly methods for its preparation. This review systematically reviews several synthetic routes to 3‐methylpyridine, alongside recent advancements, while summarizing its application progress in various organic transformations. [ABSTRACT FROM AUTHOR]

The catalytic decarboxylation of malonic acid half oxy‐ and thioesters, β‐ketocarboxylic acids, and their related compounds is a straightforward, powerful, and atom‐economical strategy for the in‐situ formation of enolates, which are important and well‐studied synthons for various functional materials and natural products. This strategy, inspired by the biosynthesis of polyketides and fatty acids, is an attractive method for synthesizing enols from carboxyl compounds with less reactive α‐hydrogen atoms under mild conditions. In addition, these reactions are environmentally friendly and are of great interest to chemists because the use of a stoichiometric amount of base can be avoided, and the only byproduct is CO2. Thus far, remarkable progress has been made, especially in the field of organocatalytic enantioselective decarboxylation reactions, allowing for the stereocontrolled formation of new C−H, C−C, C−heteroatom, and C−X bonds. This review provides a comprehensive overview of organocatalytic enantioselective decarboxylation reactions and highlights the significant progress made since 2020. In particular, it focuses on chiral catalyst systems and transition states as key parameters for decarboxylation reactions. [ABSTRACT FROM AUTHOR]

The introduction of trifluoromethylsulfinyl group into the required target molecules has become an indispensable strategy for pharmaceutical chemists to improve the success of new drug discovery. Compared with the indirect methods, direct trifluoromethylsulfinylation by employing available trifluoromethylsulfinylating reagents is an important and elegant strategy for the rapid assembly of valuable CF3S(O)‐derived organic molecules. This review focuses on the recent synthetic approaches and future perspectives of trifluoromethylsulfinyl compounds based on the indirect and direct methods in this area. These transformations proceed effectively with high yields and good functional group compatibility under mild conditions. [ABSTRACT FROM AUTHOR]

Enantioselective transformation of ubiquitous C(sp3)−H bonds into three‐dimensional chiral scaffolds is of longstanding interest to synthetic chemists. Herein, an asymmetric paired electrolysis enables a highly efficient and sustainable approach to the enantioselective alkylation of sulfonylimines via C(sp3)−H functionalization. In this protocol, anodic oxidation for benzylic radical formation and Lewis acid‐catalyzed sulfonylimine reduction on the cathode were seamlessly cross‐coupled (up to 88 % yield). Enantioenriched chiral amines containing a tetrasubstituted carbon stereocenter are accessed with high enantioselectivity (up to 96 % ee). Mechanistic studies suggest that the amine generated in situ could serve as a base to deprotonate phenols and decrease the oxidation potential of the reaction, allowing phenols with lower potentials to be preferentially oxidized. [ABSTRACT FROM AUTHOR]

The twelve principles of green chemistry illuminate the pathway in the direction of sustainable and eco-friendly synthesis, marking a fundamental shift in synthetic organic chemistry paradigms. In this realm, harnessing the power of visible light for the difunctionalization of various skeletons without employing any external oxidant or reductant, specifically termed as redox-neutral difunctionalization, has attracted tremendous interest from synthetic organic chemists due to its low cost, easy availability and environmentally friendly nature in contrast to traditional metal-catalyzed difunctionalizations. This review presents an overview of recent updates on visible-light-induced redox-neutral difunctionalization reactions with literature coverage up to May 2024. [ABSTRACT FROM AUTHOR]

Inspired by the attractive structures and functions of natural matter (such as cells, organelles and enzymes), chemists are constantly exploring innovative material platforms to mimic natural catalytic systems, particularly liquid-phase hydrogenations, which are of great significance for chemical upgrading and synthesis. Hollow structured nanoreactors (HSNRs), featuring unique nanoarchitectures and advantageous properties, offer new opportunities for achieving excellent catalytic activity, selectivity, stability and sustainability. Notwithstanding the great progress made in HSNRs, there still remain the challenges of precise synthetic chemistry, and mesoscale catalytic kinetic investigation, and smart catalysis. To this extent, we provide an overview of recent developments in the synthetic chemistry of HSNRs, the unique characteristics of these materials and catalytic mechanisms in HSNRs. Finally, a brief outlook, challenges and further opportunities for their synthetic methodologies and catalytic application are discussed. This review might promote the creation of further HSNRs, realize the sustainable production of fine chemicals and pharmaceuticals, and contribute to the development of materials science. [ABSTRACT FROM AUTHOR]

Biocatalytic preparation of chiral amines is a large and burgeoning field in organic chemistry. Many enzymes and routes have been published, including transaminases, imine reductases, reductive aminases, amine dehydrogenases and others. However, all these routes rely on some sacrificial substrate, in the form of either amine donor or cofactor regeneration substrate. Herein, we report the direct oxidative amination of p‐substituted phenols catalyzed by an evolved flavoprotein oxidase, with the consumption of only substrate and O2, and release of H2O2. The substrate scope of the reaction is studied, and is tolerant of a diverse panel including ammonia, primary and secondary amines, and amino acids. The reaction is later employed at preparative scale to generate aminated products in 50–80 % yield. This report establishes flavoprotein oxidase as a new and economical member of the chemist's toolkit for biocatalytic generation of chiral amines, acting as oxidative aminase. [ABSTRACT FROM AUTHOR]

Given her unrivalled proficiency in the synthesis of all molecules of life, nature has been an endless source of inspiration for developing new strategies in organic chemistry and catalysis. However, one feature that remains thus far beyond chemists' grasp is her unique ability to adapt the productivity of metabolic processes in response to triggers that indicate the temporary need for specific metabolites. To demonstrate the remarkable potential of such stimuli‐responsive systems, we present a metabolism‐inspired network of multicatalytic processes capable of selectively synthesising a range of products from simple starting materials. Specifically, the network is built of four classes of distinct catalytic reactions—cross‐couplings, substitutions, additions, and reductions, involving three organic starting materials—terminal alkyne, aryl iodide, and hydrosilane. All starting materials are either introduced sequentially or added to the system at the same time, with no continuous influx of reagents or efflux of products. All processes in the system are catalysed by a multifunctional heteronuclear PdII/PtII complex, whose performance can be controlled by specific additives and external stimuli. The reaction network exhibits a substantial degree of orthogonality between different pathways, enabling the controllable synthesis of ten distinct products with high efficiency and selectivity through simultaneous triggering and suppression mechanisms. [ABSTRACT FROM AUTHOR]

The Veratrum alkaloids are a class of highly intricate natural products renowned for their complex structural and stereochemical characteristics, which underlie a diverse array of pharmacological activities ranging from anti-hypertensive properties to antimicrobial effects. These properties have generated substantial interest among both synthetic chemists and biologists. While numerous advancements have been made in the synthesis of jervanine and veratramine subtypes over the past 50 years, the total synthesis of highly oxidized cevanine subtypes has remained relatively scarce. Building on the efficiency of our previously developed strategy for constructing the hexacyclic carbon skeleton of the Veratrum alkaloid family via a stereoselective intramolecular Diels-Alder reaction and radical cyclization, here we show the development of a unified synthetic approach to access highly oxidized Veratrum alkaloids. This includes the total synthesis of (–)-zygadenine, (–)-germine, (–)-protoverine and the alkamine of veramadine A, by capitalizing on a meticulously designed sequence of redox manipulations and a late-stage neighboring-group participation strategy. The Veratrum alkaloids are a class of highly intricate natural products renowned for their complex structural and stereochemical characteristics. Herein, the authors report the divergent synthesis of zygadenine, germine, protoverine and the alkamine of veramadine A, capitalizing on a late-stage neighboring group participation. [ABSTRACT FROM AUTHOR]

An E. coli cell contains ~2500 different chemicals which combine into an ordered biochemical reaction network out of which emerges a living system. A chemist taking 2500 different chemicals from a laboratory chemical cabinet and combining them together will likely cause an explosive disaster and produce an intractable chemical sludge. Systems Chemistry aspires to construct systems whose complexity rivals that of life. However, to do this we will need to learn how to combine hundreds or thousands of different chemicals together to form a functional system without descending into a disordered chemical sludge. This is the Many‐Chemicals Problem of Systems Chemistry. I explore a key strategy life employs to overcome this challenge. Namely, the combination of kinetically stable and thermodynamically activated molecules (e. g. ATP) with enzyme catalysts (e. g. histidine kinases). I suggest how the strategy could have begun at the origin of life. Finally, I assess the implications of this strategy for Systems Chemistry and how it will enable systems chemists to construct systems whose complexity rivals that of life. [ABSTRACT FROM AUTHOR]

Chloranthaceae is comprised of four extant genera (Chloranthus, Sarcandra, Hedyosmum, and Ascarina), totaling about 80 species, many of which have been widely used as herbal medicines for diverse medical purposes. Chloranthaceae plants represent a rich source of structurally interesting and diverse secondary metabolites, with sesquiterpenoids and diterpenoids being the predominant structural types. Lindenane sesquiterpenoids and their oligomers, chemotaxonomical markers of the family Chloranthaceae, have shown a wide spectrum of bioactivities, attracting significant attention from organic chemists and pharmacologists. Recent achievements also demonstrated the research value of two unique structural types in this plant family, sesquiterpenoid-monoterpenoid heterodimers and meroterpenoids. This review systematically summarizes 682 structurally characterized terpenoids from 22 Chloranthaceae plants and their key biological activities as well as the chemical synthesis of selected terpenoids. [ABSTRACT FROM AUTHOR]

The translocator protein (TSPO) is predominately localized on the outer mitochondrial membrane in steroidogenic cells. In the brain, TSPO expression, low under normal conditions, results upregulated in response to glial cell activation, that occurs in neuroinflammation. As a consequence, TSPO has been extensively studied as a biomarker of such conditions by means of TSPO-targeted radiotracers. Although [11C]-PK11195, the prototypical TSPO radioligand, is still widely used for in vivo studies, it is endowed with severe limitations, mainly low sensitivity and poor amenability to quantification. Consequently, several efforts have been focused on the design of new radiotracers for the in vivo imaging of TSPO. The present review will provide an outlook on the latest advances in TSPO radioligands for neuroinflammation imaging. The final goal is to pave the way for (radio)chemists in the future design and development of novel effective and sensitive radiopharmaceuticals targeting TSPO. [ABSTRACT FROM AUTHOR]

This review article is focused on the progress made in the synthesis of 5′-α-P-modified nucleoside triphosphates (α-phosphate mimetics). A variety of α-P-modified nucleoside triphosphates (NTPαXYs, Y = O, S; X = S, Se, BH3, alkyl, amine, N-alkyl, imido, or others) have been developed. There is a unique class of nucleoside triphosphate analogs with different properties. The main chemical approaches to the synthesis of NTPαXYs are analyzed and systematized here. Using the data presented here on the diversity of NTPαXYs and their synthesis protocols, it is possible to select an appropriate method for obtaining a desired α-phosphate mimetic. Triphosphates' substrate properties toward nucleic acid metabolism enzymes are highlighted too. We reviewed some of the most prominent applications of NTPαXYs including the use of modified dNTPs in studies on mechanisms of action of polymerases or in systematic evolution of ligands by exponential enrichment (SELEX). The presence of heteroatoms such as sulfur, selenium, or boron in α-phosphate makes modified triphosphates nuclease resistant. The most distinctive feature of NTPαXYs is that they can be recognized by polymerases. As a result, S-, Se-, or BH3-modified phosphate residues can be incorporated into DNA or RNA. This property has made NTPαXYs a multifunctional tool in molecular biology. This review will be of interest to synthetic chemists, biochemists, biotechnologists, or biologists engaged in basic or applied research. [ABSTRACT FROM AUTHOR]