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Electron pairs have an illustrious history in chemistry, from powerful concepts to understanding structural stability and reactive changes to the promise of serving as building blocks of quantitative descriptions of the electronic structure of complex molecules and materials. However, traditionally, two-electron wavefunctions (geminals) have not enjoyed the popularity and widespread use of the more standard single-particle methods. This has changed recently, with a renewed interest in the development of geminal wavefunctions as an alternative to describing strongly correlated phenomena. Hence, there is a need to find geminal methods that are accurate, computationally tractable, and do not demand significant input from the user (particularly via cumbersome and often ill-behaved orbital optimization steps). Here, we propose new families of geminal wavefunctions inspired by the pair coupled cluster doubles ansatz. We present a new hierarchy of two-electron wavefunctions that extends the one-reference orbital idea to other geminals. Moreover, we show how to incorporate single-like excitations in this framework without leaving the quasiparticle picture. We explore the role of imposing seniority restrictions on these wavefunctions and benchmark these new methods on model strongly correlated systems. [ABSTRACT FROM AUTHOR]

Sulfonamides have been played a critical role in the history of medicinal chemistry development for decades. In particular, sulfonamides display a broad spectrum in pharmaceutical drugs synthesis. This review presents a short discussion of the microwave‐assisted synthetic approaches, enhancement of sulfonamides moieties and their pharmacological applications are being discussed. During the past few decades, microwave‐assisted technology in organic synthesis has been highlighted to introducing ‐SO2NH functional group in the multi synthetic routes for the development of bioactive molecule and also assisted in the estimation of their credible mechanistic routes for the reactions. [ABSTRACT FROM AUTHOR]

The periodic table organizes chemical elements into families based on their similarity, now understood through Quantum Mechanics. However, these families were inferred from limited compounds in the nineteenth century. Since then, the number of compounds has exponentially grown, leading to the discovery of new types unknown to pioneers. This situation prompts the question of whether these families can still be discerned from the amassed data, or if their recognition is confined to specific thermochemical domains. To address this inquiry, we conducted a comprehensive exploration by comparing formulae (1771–2015) as a proxy for chemical similarity. Our findings reveal that stoichiometry not only captures a significant portion of the trends observed within families but also unveils other intriguing features of the formal structure of chemical similarity. These patterns approach equivalence classes independent of thermochemical context and demonstrate high resilience. Temporal analysis demonstrates that, since approximately 1980, similarity is diminishing due to an increasing production of unique formulae for nearly all elements. Nevertheless, chemical families endure over time and they stand out as the most robust similarity patterns. Our analysis offers compelling evidence that any study will reach the same conclusions, provided there is a sufficient diversity in input compound data. [ABSTRACT FROM AUTHOR]

This article reviews the use of natural resources in analytical chemistry throughout history. Plant extracts were employed as indicators in chemistry for identifying the acidity or alkalinity of liquids as early as the 1650s. Later, as the industrial revolution altered people's lives, synthetic chemicals were used instead. Modern techniques of analysis have replaced conventional ones as a result of advancements in physics and technology. The industrial revolution was an era of excitement until the toxic pollutants released from industries severely damaged people and the environment. The concepts of green chemistry and green analytical chemistry were proposed as potential solutions to the problems. The use of natural extracts as chemical analysis reagents has been reconsidered recently as a sustainable alternative. While new technologies such as artificial intelligence (AI) will influence future trends in analytical chemistry development, the primary goal is to move toward sustainable analytical chemistry, which includes using natural reagents and reducing the amount of chemicals consumed and waste produced. [ABSTRACT FROM AUTHOR]

The maverick American chemist Russell Earl Marker (1902–1995) is known for his studies on the fragmentation of organic mercury compounds, establishing the concept of the octane number, investigating the rearrangements of hydrocarbons and exploring the relationship between optical rotation and the configuration of organic compounds. His greatest achievement, however, is the elaboration of seminal isolation and synthetic methods of an important class of natural products that helped found a new industry, based on the pharmaceutical chemistry of steroids. The nomadic life of this extraordinary man demonstrates that the enormous obstacles thwarting the progress of science and technology can be surmounted by serendipity, acumen and devotion. However, his premature retirement from chemistry is a warning sign that every scientist is vulnerable and even the toughest man's perseverance can fade if the conditions worsen. [ABSTRACT FROM AUTHOR]

This article provides a comprehensive overview of the Nobel Prizes in Chemistry related to computational chemistry. It explores the history and development of the field, highlighting the contributions of notable scientists and their groundbreaking work in areas such as chemical dynamics, molecular structure, and electronic structure calculations. The article also discusses the Nobel Prizes awarded in specific years, recognizing the achievements of laureates and their significant research contributions. It acknowledges the underrepresentation of women in Nobel Prizes and reflects on the author's personal experiences and hopes for the future of computational chemistry. [Extracted from the article]

This Ambix special issue explores premodern alchemical ideas and practices in their entanglements with medicine. It employs diverse methods, from traditional close reading to the new distant-reading framework of computational humanities, to investigate alchemical thought over a timespan of several centuries. In medieval times, everyday practices could offer heuristic models of material transformation – such as the fermentation of bread as a model for metallic transmutation (Schmechel). Paracelsus relied on "fire" to link his natural philosophy with his medical alchemy; new computational methods show how his ideas evolved over time (Hedesan). Early modern medical pluralism favoured the thriving of chemical medicine in Italy; diplomatic efforts introduced chemical remedies into acknowledged pharmacopoeias (Clericuzio). An English physician offers William Cavendish both practical distillation recipes and the hope of learning more about the principles of chemistry (Begley). In eighteenth-century France, Diderot draws on chemical ideas to blur the conceptual boundary between living and non-living matter (Wolfe). The papers largely adhere to integrated history and philosophy of science (iHPS) and to a pragmatist "operational ideal of knowledge" (Chang). They showcase the interdisciplinarity of premodern scientific thought and examine how medicine and alchemy, but also theory and (everyday) practice informed each other fruitfully across the ages. [ABSTRACT FROM AUTHOR]

The document titled "Centenary Workshop on the Bifurcation of Acidity - Protonism vs. Electronism" discusses a workshop that took place in Coburg, Germany, organized by Klaus Ruthenberg. The workshop focused on the history and philosophy of chemistry, specifically the debate between the protonist and electronist positions regarding acidity. The workshop featured contributions from various scholars, including Hasok Chang and Eric Scerri, who supported the electronistic position. Other topics discussed included the sensory background of the notion of acid, the nature of acids as natural kinds, and the development of acid-base concepts and redox chemistry. The workshop aimed to continue the research on acidity and foster collaboration among scholars in the field. [Extracted from the article]

On May 1, 1965, Roald Hoffmann and R. B. Woodward published their second joint communication, Selection Rules for Concerted Cycloaddition Reactions, in the Journal of the American Chemical Society. Herein is presented a historical analysis of Woodward and Hoffmann's determination of the mechanism of cycloadditions. This analysis is based on thorough analyses with Roald Hoffmann of his 1964 and 1965 laboratory notebooks and his archived documents and on numerous in‐person, video, and email interviews. This historical research pinpoints several seminal moments in chemistry and in the professional career of Hoffmann. For example, now documented is the fact that Woodward and Hoffmann had no anticipation that their collaboration would continue after the publication of their first 1965 communication on electrocyclizations. Also pinpointed is the moment in Hoffmann's professional and intellectual trajectories that he became a full‐fledged, equal collaborator with Woodward and Hoffmann's transition from a "calculator" to an "explainer." [ABSTRACT FROM AUTHOR]

Transition metal‐catalyzed carbene transfer reactions have a century‐old history in organic chemistry and are a primary method for the synthesis of cyclopropanes. Much of the work in this field has focused on the use of diazo compounds and related precursors, which can transfer a carbene fragment to a catalyst with concomitant loss of a stable byproduct. Despite the utility of this approach, there are persistent limitations in the scope of viable carbenes, most notably those lacking stabilizing substituents. By coupling carbene transfer chemistry with two‐electron redox cycles, it is possible to expand the available starting materials that can be used as carbene precursors. In this Minireview, we discuss emerging catalytic reductive cyclopropanation reactions using either gem‐dihaloalkanes or carbonyl compounds. This strategy is inspired by classic stoichiometric transformations, such as the Simmons–Smith cyclopropanation and the Clemmensen reduction, but instead entails the formation of a catalytically generated transition metal carbene or carbenoid. We also present recent efforts to generate carbenes directly from methylene (CR2H2) groups via a formal 1,1‐dehydrogenation. These reactions are currently restricted to substrates containing electron‐withdrawing substituents, which serve to facilitate deprotonation and subsequent oxidation of the anion. [ABSTRACT FROM AUTHOR]

The research work of history of catalysis science can trace back to the beginning of Republic of China. The earlier work always affiliated to the history of chemistry, e.g. the chapter of catalysis in History of Chemistry. Thereafter, it can be gradually found in some monographs on catalysis, e.g. The Newest Chemical Engineering Series showing at the beginning of these books. After the foundation of the People’s Republic of China, the research work of catalysis starts to be independent, e.g. the pioneer work of Zhang Dayu, Guo Xiexian, etc. Besides, it also found in the books of chemical history, of catalysis science and of catalysis used as key technique. Recently, the monographs of history of catalysis science have been published, e.g. Documents of History of Catalysis (Cuihua Shiliao), Scientist of Catalysis in China., all edited by Xin Qin, etc. [ABSTRACT FROM AUTHOR]

Copyright of Nachrichten aus der Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Musks, the foundation of many perfumes, as well as other ingredients of perfumes, were critical objects of study for establishing theoretical concepts about large ring chemical compounds and polymerization in the 1920s and 1930s. Because fragrance chemistry has been underdeveloped in the historiography, doubtless partly because it has become associated with the feminine, this has been ignored in the historiography. This essay highlights the strategic importance of perfume research, looking in particular at the work of Leopold Ružičkač, 1939 Nobel laureate in chemistry who had close ties to the fragrance industry, and Wallace Carothers at DuPont, whose well-known work on polymerization was intimately concerned with large ring compounds, including musk, and which indeed led to DuPont producing a synthetic musk in the 1930s. [ABSTRACT FROM AUTHOR]

Sanfte Chemie was a concept formulated in the 1980s in Germany by a group of environmentally conscious scholars. It emerged within a unique environment, marked by its radical critique of dominant forms of rationality, and against the rich background of German philosophical technocritical traditions. Its purpose was to profoundly reshape the practice of chemistry and the organization of the chemical industry along the lines of sustainability. In contrast to later concepts like green or sustainable chemistry, Sanfte Chemie went beyond setting new research directions; it critically reevaluated the entire epistemological foundation upon which the science of chemistry was built. Under the auspices of the German Green Party, the concept flourished in the 1980s before falling out of grace in the following decade. While largely deemed overly radical in its time and then subsequently forgotten, Sanfte Chemie not only anticipated some of the most promising trends in sustainability science today but also offered unique insights that may shed new light on the challenges of the ongoing environmental crisis. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Molecular Science is the property of Journal of Molecular Science Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

During the eighteenth century, authors of chemical treatises and courses on chemistry often introduced their work with a chapter devoted to the history of chemistry. While there may have been different reasons for the use of history, its importance was never seriously questioned. However, when Antoine Laurent Lavoisier (1743–1794) took a professional interest in chemistry in the early 1770s, he progressively became uneasy with this literary tradition. In this essay, I intend to explore the ways in which Lavoisier looked at the history of chemistry and to show how, from the 1780s onwards, he began to adopt a hostile attitude towards historical erudition. This vision, which culminated in the publication of the Traité élémentaire de chimie (Paris, 1789), was not only the result of a stylistic preference but constituted a direct attack on a way of doing chemistry from which Lavoisier intended to distance himself. [ABSTRACT FROM AUTHOR]

This paper presents life and work of Friedlieb Ferdinand Runge, an unusual chemist, ignored for a long time. There are discussed his researches in natural products and coal tar, the discovery of caffeine and priority claims on the discovery of quinine. Important industrial activities at the Oranienburg factory are described, including the ‘German guano’. Important issues are the discussion of alternative chemical theories by the anti-atomist Runge, as well as his occupation with the relation Chemistry-Art, expressed in his Musterbilder, also a forerunner of chromatography.

Transition from the traditional linear economy to a circular economy is the key to reducing the amount of plastic that ends up in the environment and recovering value from the waste. However, energy-efficient, environmentally friendly, and economical technologies to recycle the mounting volume of low-grade plastic waste are lacking when compared to the low cost of primary fossil-based plastic production. This led to extensive efforts to identify methods that mitigate the waste that already exists and develop new polymers to eliminate the poor recyclability problem caused by current materials. Polymers capable of depolymerizing back to their own monomers provide a promising solution. This chemical recycling process has the potential to eliminate contaminants, selectively depolymerize a particular polymer from a waste stream, and recover high-purity monomers from contaminated wastes; however, the process must be energy-efficient and economical. This review discusses recent advances in chemical design of polymers that can depolymerize back to their monomers with an emphasis on strategies that shift the monomer–polymer equilibrium to enable reversible depolymerization and polymerization. Novel approaches developed for ring-opening polymerization and ring-closing depolymerization, reversing free radical polymerization, and reversible reactions that enable depolymerization of highly crosslinked thermosets to small molecular monomers are reviewed. Self-immolative polymers, which have a long history of chemistry innovation to realize the balance between stability and rapid depolymerization, are briefly discussed to serve as an inspiration for new polymer designs. Any new materials designed should have at least matching properties and stabilities compared to existing materials. Thus, this review reflects the status of current research that not only demonstrates the reversible polymerization chemistry but also achieves outstanding material properties. [ABSTRACT FROM AUTHOR]

The 13th International Conference on the History of Chemistry took place in Vilnius, Lithuania and was organized by the History of Chemistry Working Party of the European Chemical Society (EuChemS) and other organizations. The conference brought together researchers and enthusiasts from around the world and featured presentations from 88 participants representing twenty countries. The event aimed to promote interest in the history of chemistry and foster the heritage of chemical science in Lithuania. The next conference in the series will be held in Valencia, Spain in 2025. [Extracted from the article]

The central metaphor of nature as a watch Ims colored the debate about natural theology silice Paley and Darwin. However. a chemical interpretation of natural history will dger because cheinical systems do not work like watches. Here. a natural history of chemical constraints proposed by R. J. P. Williams is interpreted Nirough Joseph Earley's two modes of chemical becoming" with classical realism and the philosophy Of emergence. 171is interpretation shi#s attention./)00111 a system's irreducible complexity to its irreducible novelty, focusing on its novel existence and its transcendental truth, goodness, and beauty. A view of natural history in which irreducible novelty evolves through chemistry has several advantages: it accommodates continuous change (giviiig direction to a gradual mechanism of evolution) and irreversible change (providing an importantyet limited rolejor chance rather than denying its existence oroveremphasizing its power). A chemical perspective perceives the inherent "makeability" and manifest order of the universe. [ABSTRACT FROM AUTHOR]

The widely recognized 12 principles of green chemistry, introduced in 1998, have become a focal point for environmentally conscious chemists worldwide. These principles are regarded as a comprehensive summary of the achievements of green chemistry and a roadmap for future advancements in the field, aligning chemistry with sustainability goals. They have been hailed as groundbreaking in addressing pressing global challenges, including environmental and climate crises. However, a closer examination reveals a more nuanced perspective. Criticisms have emerged, asserting that these principles may stifle the creativity of emerging chemists and distort the history of green chemistry. Dissenting voices are growing, prompting scholars to reevaluate their effectiveness and relevance. It appears that the 12 principles provide an overarching narrative and a common language to practitioners of green chemistry but their success does not proceed from their 'scientific' qualities but should be rather understood in socio-historical terms. Analysing these principles provides insights into the mindset and collective identities of chemists, highlighting how underlying value-driven frameworks shape scientific discourse. It becomes evident that these frameworks can be co-opted and persist unquestioned for extended periods. The objective of this article is to demystify the 12 principles, stimulating dialogue on the necessity of self-reflection within scientific fields that heavily rely on value-laden sustainability-oriented terminology. [ABSTRACT FROM AUTHOR]

The book "The History of Chemistry at Ludwig-Maximilians-University Munich" by Wolfgang Beck describes the development of chemistry at LMU from its beginnings in Ingolstadt and Landshut to the integration of the Bavarian State Laboratory. It includes short biographies of professors who have worked at the university and showcases the architectural development of chemistry at LMU. The book "LMU Chemistry: A History of Chemistry at Ludwig-Maximilians-University Munich" by Hubert Schmidbaur covers various topics such as research areas, Nobel laureates, and the study of chemistry at LMU. It also includes short biographies of 70 scientists who have worked at the chemical research facilities of LMU. The author, Hubert Schmidbaur, is a renowned chemist and former professor at the Technical University of Munich. [Extracted from the article]

Convergence education, driven by compelling or complex socio-scientific problems, is an approach to bring cultural relevance into secondary STEM education. National trends show the need to increase the STEM workforce by leveraging educational research and innovative practices within the secondary level to increase student interest prior to graduating high school. We introduced CReST (Culturally Relevant STEM) in a US high school pilot study. Student participants included 276 Chemistry students and 19 World History I students. The study also engaged four (4) high school teachers in chemistry and social studies with the challenge of cultural heritage conservation through the lens of the (physicochemical) life cycle of mural paintings in Europe. Teachers were provided with (1) professional development; (2) a digital curriculum; and (3) modular kits for hands-on learning. The research focused qualitatively on the experiences from the teacher and students as well as quantitatively to assess whether there was an increase in student academic performance. We found a statistically significant gain with respect to Chemistry (4.0%) and World History (13.4%) content. Students and teachers responded with overwhelming positivity in individual and focus-group interviews. This amplifies the further need of convergent educational approaches in high school STEM education to enhance engagement and increase student learning. [ABSTRACT FROM AUTHOR]

Copyright of Nachrichten aus der Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Nachrichten aus der Chemie is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

"Molecular World: Making Modern Chemistry" by Catherine M. Jackson is a book that explores the development of organic chemistry through empirical observations in the laboratory. The book is divided into three sections, focusing on the work of Justus Liebig, August Wilhelm Hofmann, and Albert Ladenburg. It discusses the impact of Liebig's Kaliapparat device on organic analysis and the financial challenges faced by Liebig. The book also highlights Hofmann's experimental work and his development of new reactions of amines with alkyl halides. While the author's arguments about the role of theory in organic chemistry are not entirely convincing, the book offers a thought-provoking perspective on the subject. [Extracted from the article]

A select history of dichlorocarbene chemistry between 1950 and 2010 will be presented. This is not a comprehensive review; rather, it is a personal perspective on the contributions of two respected colleagues, the reactive intermediate that spanned their research efforts, and their important contributions to organic synthesis and mechanistic thinking. [ABSTRACT FROM AUTHOR]

Copyright of Revista Didasc@lia: Didáctica y Educación is the property of Universitaria de Las Tunas, Centro de Estudios de Didactica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Most chemistry textbooks claim that oxygen was discovered almost simultaneously by Carl Scheele and Joseph Priestley about 250 years ago. Priestley obtained oxygen by heating mercuric oxide (1774), and Scheele -by heating NaNO3, as well as by dissolving pyrolusite in sulfuric acid (1772). The name "oxygen" was given a few years later (1779) by Antoine Lavoisier. This great scientist, often accused of taking advantage of the discoveries of others, conducted experiments related to the decomposition of water vapour over heated iron, as well as the synthesis of water from hydrogen and oxygen. His work was of great importance because it revealed the elemental nature of oxygen and its role in the processes of combustion and respiration. The present article draws attention to the prehistory of the "oxygen theory". It emphasises the natural philosophy of a forgotten alchemist, healer, and diplomat - Michael Sendivogius (1566-1636) - who popularised his belief that the substance ("Water of life that does not wet the hands") obtained by heating the "Central Salt" (nitre, KNO3) is part of the air. It is the "secret food of life" used invisibly by every living thing. [ABSTRACT FROM AUTHOR]

Fuels for automobiles and feedstocks for chemical industries are conventionally manufactured by refining petroleum. However, gasoline or diesel has also been produced synthetically from various carbon-bearing feedstocks such as coal or biomass. The pioneering technology for realizing synthetic fuels is the Fischer–Tropsch (FT) process, which was developed during 1923–1925 in Germany. Today, the major FT technology users, which include international oil companies such as Shell, ExxonMobil and Sasol, perceive that synthetic fuels prepared from synthesis gas, (CO + H2) will be a possible option as future alternative fuels. The chemistry and history of the development of the FT process, its industrial implementation over the years and its relevance for the future are discussed in this article. We have also given a general overview of the catalysts used for FT technology and mechanistic details proposed over the years and related processes. [ABSTRACT FROM AUTHOR]

Graph John Perkins who, after a ten-year struggle with cancer, died just short of his eightieth birthday, was a prominent historian of chemistry, particularly French, and for many years a stalwart of the Society for the History of Alchemy and Chemistry (SHAC). The first stage was a roundtable discussion, "Chemistry Courses and the Construction of Chemistry, 1750-1820", at the sixth International Conference on the History of Chemistry held in Leuven in 2007. As Bernadette Bensaude-Vincent puts it, Perkins was a "key actor in the renewal of historical studies in chemistry during the past decades.". [Extracted from the article]

The vocabulary of the chemical sciences consists in part of words and phrases many of which are of a technical nature while others are derived from or related to everyday language. Many of the words are so-called polysemes, that is, they are used with different meanings either in common language or in the technical language of other sciences. The study of the origin and migration (or transfer) of words in science provides additional insights in how science has developed historically and interacted with the cultural domain. One type of word migration is between the scientific and socio-cultural domains, while another is restricted to the transfer between different scientific disciplines or sub-disciplines. This paper discusses and exemplifies a select number of chemically related words and phrases from a historical perspective. Among them are commonly known words such as ‘radical,’ ‘catalyze,’ and ‘litmus test’ which are used not only as technical terms in chemistry but also, in figurative and metaphorical senses, in everyday language.

A COMMENTED TRANSLATION OF ACIDS AND BASES BY GILBERT NEWTON LEWIS. Gilbert Newton Lewis was a distinguished scientist in 20th century History of Chemistry. His work remains relevant for physical chemistry, organic chemistry and coordination chemistry nowadays. Lewis is well known by his propose for chemical bond, based on electron sharing. In 1923 he published two theoretical explanations for acids and bases: the former collaborating with Bronsted and Lowry and the later in his book Valence and the Structure of Atoms and Molecules (1923). In this book, the role of electron pairs in acid base reactions was highlighted decentering explanations from detachment/transfer of hydrogen ion. As a result, more substances could be classified as acids and bases. Also, in the context of organic and coordination chemistry new interpretations for reaction mechanisms showed up. The paper translated here, Acids and Bases (1938), makes a strong empirical description of acids and bases behavior. Lewis designed phenomenological criteria as speed of neutralization reactions, strength of the species acid-base titrations, and its applications as catalysts. In this manuscript, we carried out a commented translation of Lewis Acids and Bases published in 1938, considering it an inspiring source for research and educational applications for Portuguese speaking countries.

The article titled "Foreword" introduces the current issue of Acta Baltica Historiae et Philosophiae Scientiarum, which focuses on the philosophical legacy of Rein Vihalemm. The issue includes discussions on Vihalemm's concept of practical realism and his methodological distinction of the sciences. The contributions in the issue examine foundational ideas of Vihalemm's philosophy of science and expand upon them. The article also mentions the inclusion of an article on the topic of values in science and introduces a new section titled "News and Events." [Extracted from the article]

In the current debate on the origins of science-based legislation, it is important to clarify the historical perspective on the origins of Portuguese food regulation. This article situates food regulation in the European context at the end of the 19th century and contextualizes the Portuguese case until the beginning of the 20th century. It provides the framework of the dynamics of regulation in Portugal and the internalization of scientific practices of these first legislative movements. Although it identifies clear traces of political selection regarding legislation, the elaboration of regulations seems to have emerged from a movement of scientific experts, perhaps outside the sphere of business (as is the case in Europe). The article also analyses the evolution of food legislation in Portugal until the consolidation of these practices in 1903 and their revision in 1905.

This is a short overview of the life and achievements of Justus von Liebig. Clearly, this can only be an incomplete and somewhat personal view of the author, who has been a professor of inorganic chemistry at Justus Liebig University since 2002. Having already been interested in the work of Liebig for many years, and with a strong connection to the Liebig Museum in Giessen, the author hopes to provide some useful information about this great chemist, one of the founders of modern chemistry. The reader should find many interesting, probably new, facts about Liebig’s major impact on chemistry, agriculture, nutrition, and pharmacology.

Mimics of protein secondary and tertiary structure offer rationally‐designed inhibitors of biomolecular interactions. β‐Sheet mimics have a storied history in bioorganic chemistry and are typically designed with synthetic or natural turn segments. We hypothesized that replacement of terminal inter‐β‐strand hydrogen bonds with hydrogen bond surrogates (HBS) may lead to conformationally‐defined macrocyclic β‐sheets without the requirement for natural or synthetic β‐turns, thereby providing a minimal mimic of a protein β‐sheet. To access turn‐less antiparallel β‐sheet mimics, we developed a facile solid phase synthesis protocol. We surveyed a dataset of protein β‐sheets for naturally observed interstrand side chain interactions. This bioinformatics survey highlighted an over‐abundance of aromatic–aromatic, cation‐π and ionic interactions in β‐sheets. In correspondence with natural β‐sheets, we find that minimal HBS mimics show robust β‐sheet formation when specific amino acid residue pairings are incorporated. In isolated β‐sheets, aromatic interactions endow superior conformational stability over ionic or cation‐π interactions. Circular dichroism and NMR spectroscopies, along with high‐resolution X‐ray crystallography, support our design principles. [ABSTRACT FROM AUTHOR]

Copyright of Revista Didasc@lia: Didáctica y Educación is the property of Universitaria de Las Tunas, Centro de Estudios de Didactica and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The concept of green chemistry dominated the imagination of environmentally-minded chemists over the last thirty years. The conceptual frameworks laid by the American Environmental Protection Agency scholars in the 1990s constitute today the core of a line of thinking aimed at transforming chemistry into a sustainable science. And yet, in the shadow of green chemistry, a broader, even if less popular, concept of sustainable chemistry started taking shape. Initially, it was either loosely associated with green chemistry or left undefined as a distinct but generaly different approach. In such a vague form, it was endorsed by the organizations such as OECD and the IUPAC in the late 1990s. It was not until the 2010s however, when it solidified as a separate more embracing and more overarching tradition that could compete with green chemistry by offering insights that the latter lacked. Sustainable chemistry seeks to transcend the narrow focus on chemical synthesis and embrace a much more holistic view of chemical activities including social responsibility and sustainable business models. Due to an interesting historical coincidence, it was in Germany where sustainable chemistry took roots and became institutionalized for the first time. It was thanks to German exceptionalism and the unwillingness of German scholars to embrace the "green" terminology originating from the US, the concept of sustainable chemistry could safely mature and develop in the German-speaking world, before reaching a high degree of formalization with dedicated journals, founding articles, and programmatic principles aspiring to transform the entire chemical enterprise in the years to come. [ABSTRACT FROM AUTHOR]

Based upon the demarcation between Elementalism and Atomism Chemistry from the perspective of the long-term history of chemistry, the authors re-examine the Berthollet-Proust controversy on the three types of chemical compounds, pointing out that Berthollet proposed the law of indefinite proportions by deduction, while Proust proposed the law of definite proportions by induction. The controversy is beyond the framework of affinity chemistry and entail a synthesis of meta-chemical thinking and experiments. Proust's discovery of the law of definite proportions not only function as Bacon's "instances of lamp" to invoke Dalton and other atomism chemists to envision atomism, but also served as a bridge linking the two meta-chemistries. John Dalton, the third choice, envisioned his atomism by abduction. The case study on "the Berthollet-Proust controversy and Dalton's resolution" mandates a reinvestigation of the crucial role of the system of experiments and the evolution of chemistry according to the demarcation between the established branches of Elementalism and Atomism Chemistry. [ABSTRACT FROM AUTHOR]

Keywords: electrochemical oxidation; benzylic C(sp 3)-H amidation; Ritter-type reaction; external mediator free; oxidant free; N -benzylamides EN electrochemical oxidation benzylic C(sp 3)-H amidation Ritter-type reaction external mediator free oxidant free N -benzylamides 2969 2978 10 08/31/23 20230915 NES 230915 Graph Amides are abundant in almost all living organisms, and the amide group is one of the most common and versatile functional groups in a number of peptides and proteins, [1] pharmaceuticals, [2] agrochemicals, [3] and fluorescent sensor, [6] etc. Electrochemical Benzylic C(sp3)-H Amidation via Ritter-Type Reaction in the Absence of External Mediator and Oxidant N -(1-(4'-Ethyl-[1,1'-biphenyl]-4-yl)ethyl)acetamide (3c) The product was purified by silica gel column chromatography with PE/EtOAc (1:1, v/v); white solid; yield: 61.5 mg (77%); mp 144-146 °C. N -(1-(4'-Methyl-[1,1'-biphenyl]-4-yl)ethyl)acetamide (3b) The product was purified by silica gel column chromatography with PE/EtOAc (1:1, v/v); white solid; yield: 59.1 mg (78%); mp 160-162 °C. [Extracted from the article]

The spectre of the machine and the mechanical jurisprudence that accompanies it have dominated patent law for over a century. This article offers three examples where we can see the influence of the figure of the machine in patent law: in the way the history of organic chemistry has been viewed, in the way that the law first interacted with biological inventions, and finally in the way that many commentators think about AI-machine generated inventions. I end by offering a different way of thinking about inventions that allows us to move beyond the spectre of the machine to give space for more speculative empirical inventions. [ABSTRACT FROM AUTHOR]

Context. The G31.41+0.31 Unbiased ALMA sPectral Observational Survey (GUAPOS) project targets the hot molecular core (HMC) G31.41+0.31 (G31) to reveal the complex chemistry of one of the most chemically rich high-mass star-forming regions outside the Galactic center (GC). Aims. In the third paper of the project we present a study of nine O-bearing (CH3OH, 13CH3OH, CH318OH , CH3CHO, CH3OCH3, CH3COCH3, C2H5OH, aGg′-(CH2OH)2, and gGg′-(CH2OH)2) and six N-bearing (CH3CN,13CH3CN, CH313CN, C2H3CN, C2H5CN, and C2H513CN) complex organic molecules toward G31. The aim of this work is to characterize the abundances in G31 and to compare them with the values estimated in other sources. Moreover, we searched for a possible chemical segregation between O-bearing and N-bearing species in G31, which hosts four compact sources as seen with higher angular resolution data. In the discussion we also include the three isomers of C2H4O2 and the O- and N-bearing molecular species NH2CHO, CH3NCO, CH3C(O)CH2, and CH3NHCHO, which were analyzed in previous GUAPOS papers. Methods. Observations were carried out with the interferometer ALMA and cover the entire Band 3 from 84 to 116 GHz (~32 GHz bandwidth) with an angular resolution of 1.2″ × 1.2″ (~4400 au × 4400 au) and a spectral resolution of ~0.488 MHz (~1.3–1.7 km s−1). The transitions of the 14 molecular species were analyzed with the tool SLIM of MADCUBA to determine the physical parameters of the emitting gas. Moreover, we analyzed the morphology of the emission of the molecular species. Results. The values of abundances with respect to H2 in G31 range from 10−6 to 10−10 for the different species. We compared the abundances with respect to methanol of O-bearing, N-bearing, and O- and N-bearing COMs in G31 with 27 other sources, including other hot molecular cores inside and outside the GC, hot corinos, shocked regions, envelopes around young stellar objects, and quiescent molecular clouds, and with chemical models. Conclusions. From the comparison with other sources there is not a unique template for the abundances in hot molecular cores, pointing toward the importance of the thermal history for the chemistry of the various sources. The abundances derived from the chemical models are in good agreement, within a factor of 10, with those of G31. From the analysis of the maps we derived the peak positions of all the molecular species toward G31. Different species peak at slightly different positions, and this, together with the different central velocities of the lines obtained from the spectral fitting, point to chemical differentiation of selected O-bearing species. [ABSTRACT FROM AUTHOR]

Chalcones are a fascinating and well‐studied group of organic molecules. Synthesis of chalcones has been one of the essential areas of organic synthesis over the last few decades because of their immense therapeutic and excellent photophysical properties. Furthermore, these chalcone derivatives can be utilized to make a variety of heterocyclic compounds, especially five‐ and six‐membered heterocycles. Heterocyclic compounds have a long history in chemistry, primarily in pharmaceuticals. However, synthesizing some specific heterocyclic molecules remains challenging and requires multistep processes with few possible intermediates. Chalcones can be considered as one of the most useful, readily available intermediates in heterocyclic synthesis. Herein, the synthesis of various potential heterocyclic compounds using chalcones as an intermediate is elaborated. This review shows the untapped potential of chalcones in organic synthesis. Also, it will assist the chemist in designing new heterocycles by adopting these strategies. [ABSTRACT FROM AUTHOR]

Catherine M. Jackson's book, "Molecular World: Making Modern Chemistry," explores the rise of synthetic organic chemistry in the 19th century. Jackson argues that this development has been overlooked by historians and seeks to provide a comprehensive account of its significance. She highlights the role of experimental skills and older concepts, rather than the new theory of molecular structure, in driving organic synthesis. The book also examines the material culture of the chemical laboratory, experimental instruments and methods, the relationship between science, technology, and industry, and the connection between experiment and theory. Jackson introduces the concept of "laboratory reasoning" to explore how chemists mediated the tension between experiment and theory. While the book does not provide a detailed definition of laboratory reasoning, it emphasizes the importance of systematic comparison of experimental results and the use of chemical formulae as heuristic tools. Overall, the book offers a compelling account of the rise of synthetic organic chemistry and provides valuable insights into the history of chemistry. [Extracted from the article]

Carsten Reinhardt has been awarded the Morris Award for 2024 by the Society for the History of Chemistry. He is recognized for his exceptional work in the recent history of chemistry and the chemical industry. Reinhardt's research explores various dimensions of chemistry, including its instrumental, theoretical, commercial, industrial, and regulatory aspects. His notable contributions include a book on the impact of physical instrumentation on chemistry in the second half of the twentieth century, as well as studies on the interplay between industry and academia in the field. Reinhardt's work also delves into the perception of chemistry as both a science and an industry, and its evolving role in health and environmental contexts. He is commended for his collaborative approach and his ability to bridge the gap between science and politics. Reinhardt's achievements have greatly benefited the field of historical chemistry and chemical technology. The Morris Award, which honors scholarly achievement in the history of modern chemistry or the chemical industry, will be presented to Reinhardt at an upcoming meeting. [Extracted from the article]