Recent advances and new concepts for the synthesis of axially stereoenriched biaryls

2015 ◽  
Vol 44 (11) ◽  
pp. 3418-3430 ◽  
Author(s):  
J. Wencel-Delord ◽  
A. Panossian ◽  
F. R. Leroux ◽  
F. Colobert

Over the past decade the field of the synthesis of axially chiral compounds has been rapidly expanding. Not only key advances have been achieved concerning the already established strategies but also new synthetic routes have been devised. This review showcases the recent developments in this domain.

Molecules ◽  
2020 ◽  
Vol 25 (21) ◽  
pp. 4906
Author(s):  
Jurriën W. Collet ◽  
Thomas R. Roose ◽  
Bram Weijers ◽  
Bert U. W. Maes ◽  
Eelco Ruijter ◽  
...  

Isocyanides have long been known as versatile chemical reagents in organic synthesis. Their ambivalent nature also allows them to function as a CO-substitute in palladium-catalyzed cross couplings. Over the past decades, isocyanides have emerged as practical and versatile C1 building blocks, whose inherent N-substitution allows for the rapid incorporation of nitrogeneous fragments in a wide variety of products. Recent developments in palladium catalyzed isocyanide insertion reactions have significantly expanded the scope and applicability of these imidoylative cross-couplings. This review highlights the advances made in this field over the past eight years.


2010 ◽  
Vol 425 ◽  
pp. 107-166 ◽  
Author(s):  
George Gejo ◽  
Joseph Kuruvilla ◽  
Abderrahim Boudenne ◽  
Thomas Sabu

This review aims at reporting on very recent developments in the, properties and applications of Green Composites. One very important aspect of green composites is that they can be designed and tailored to meet different requirements. Recent advances in natural fiber development offer significant oppurtunities for improved materials from renewable resources. Biocomposites offer a significant non-food market for crop-derived fibres and resins. Considerable growth has been seen in the use of biocomposites in the automotive and decking markets over the past decade or so, but application in other sectors has hitherto been limited. Recent developments of different biodegradable polymers and biocomposites are discussed in this review article.


2020 ◽  
Vol 74 (11) ◽  
pp. 883-889
Author(s):  
Johanna Frey ◽  
Sabine Choppin ◽  
Françoise Colobert ◽  
Joanna Wencel-Delord

N–C axial chirality, although disregarded for decades, is an interesting type of chirality with appealing applications in medicinal chemistry and agrochemistry. However, atroposelective synthesis of optically pure compounds is extremely challenging and only a limited number of synthetic routes have been designed. In particular, asymmetric N-arylation reactions allowing atroposelective N–C bond forming events remain scarce, although great advances have been achieved recently. In this minireview we summarize the synthetic approaches towards synthesis of N–C axially chiral compounds via stereocontrolled N–C bond forming events. Both organo-catalyzed and metal-catalyzed transformations are described, thus illustrating the diversity and specificity of both strategies.


2020 ◽  
Vol 92 (5) ◽  
pp. 751-765 ◽  
Author(s):  
Alexander Fawcett

AbstractBicyclo[1.1.0]- and 1-azabicyclo[1.1.0]butanes are structurally unique compounds that exhibit diverse chemistry. Bicyclo[1.1.0]butane is a four-membered carbocycle with a bridging C(1)-C(3) bond and 1-azabicyclo[1.1.0]butane is an analog of bicyclo[1.1.0]butane featuring a nitrogen atom at one bridgehead. These structures are highly strained, allowing them to participate in a range of strain-releasing reactions which typically cleave the central, strained bond to deliver cyclobutanes or azetidines. However, despite these molecules being discovered in the 1950s and 1960s, and possessing a myriad of alluring chemical features, the chemistry and applications of bicyclo[1.1.0]- and 1-azabicyclo[1.1.0]butanes remain underexplored. In the past 5 years, there has been a resurgent interest in their chemistry driven by the pharmaceutical industry’s increasing desire for new methods to access cyclobutanes and azetidines. This short review intends to provide a timely summary of the most recent developments in the chemistry of bicyclo[1.1.0]- and 1-azabicyclo[1.1.0]butane to highlight the diverse chemistry they can access, their value as synthetic precursors to cyclobutanes and azetidines, and to identify areas for future research.


1988 ◽  
Vol 27 (1) ◽  
pp. 81-83
Author(s):  
Nadeem A. Burney

Its been long recognized that various economies of the world are interlinked through international trade. The experience of the past several years, however, has demonstrated that this economic interdependence is far greater than was previously realized. In this context, the importance of international economic theory as an area distinct from general economics hardly needs any mentioning. What gives international economic theory this distinction is international markets for some goods and effects of national sovereignty on the character of economic activity. Wilfred Ethier's book, which incorporates recent developments in the field, is an excellent addition to textbooks on international economics for one- or twosemester undergraduate courses. The book mostly covers standard topics. A distinguishing feature of this book is its detailed analysis of the flexible exchange rates and a discussion of the various approaches used for their determination. Within each chapter, the author has extensively used facts, figures and major events to clarify the concepts in the light of the theoretical framework. The book also discusses, in a fair amount of detail, the existing international monetary system and the role of various international organizations.


2019 ◽  
pp. 451-458
Author(s):  
Peter W. Rein

Developments in the technology of production of sugar from sugarcane tend to be incremental improvements in an effort to reduce costs and boost revenue. Nonetheless the developments are significant and contribute to sustainable sugarcane enterprises. Some technologies have adapted to changing environmental conditions, and more attention is being given to boosting revenue through associated activities, particularly in enhancing the potential for sugarcane operations to exploit the energy value of sugarcane. This paper outlines recent developments of interest in processing sugarcane.


2017 ◽  
Vol 40 (3) ◽  
pp. 295-310
Author(s):  
Sabine Wilke

Every late spring since 1951, the Wiener Festwochen bring performers from around the world to Vienna for an opportunity to share recent developments in performance styles and present them to a Viennese public that seems to be increasingly open to experimentation. These festival weeks solidify a specific form of Viennese self-understanding and self-representation as a culture that is rooted in performance. This essay seeks to link two recent Austrian performances—one of them was part of the Wiener Festwochen in 2016, the other was staged in downtown Linz during the past few years—to this Austrian and specifically Viennese culture of performance by reading them as contemporary articulations of a tradition of radical performance art that can be traced back to the Viennese Actionism of the sixties and later feminist articulations in the seventies and eighties. They play on the dramatic effect of these actions, specifically their joy in cruelty, chaos, and orgiastic intoxication, by staging regressions and thus making visible what has been dammed up and repressed in contemporary society.1 Just as their historical models, these two performances merge the performing and the fine arts and they highlight provocative, controversial, and, at times, violent content. But they do it in an interspecies context that adds an entire layer of complexity to the project of societal and cultural critique.


2019 ◽  
Vol 26 (13) ◽  
pp. 2330-2355 ◽  
Author(s):  
Anutthaman Parthasarathy ◽  
Sasikala K. Anandamma ◽  
Karunakaran A. Kalesh

Peptide therapeutics has made tremendous progress in the past decade. Many of the inherent weaknesses of peptides which hampered their development as therapeutics are now more or less effectively tackled with recent scientific and technological advancements in integrated drug discovery settings. These include recent developments in synthetic organic chemistry, high-throughput recombinant production strategies, highresolution analytical methods, high-throughput screening options, ingenious drug delivery strategies and novel formulation preparations. Here, we will briefly describe the key methodologies and strategies used in the therapeutic peptide development processes with selected examples of the most recent developments in the field. The aim of this review is to highlight the viable options a medicinal chemist may consider in order to improve a specific pharmacological property of interest in a peptide lead entity and thereby rationally assess the therapeutic potential this class of molecules possesses while they are traditionally (and incorrectly) considered ‘undruggable’.


2020 ◽  
Vol 16 (4) ◽  
pp. 454-486 ◽  
Author(s):  
Smita Verma ◽  
Vishnuvardh Ravichandiran ◽  
Nihar Ranjan ◽  
Swaran J.S. Flora

Nitrogen-containing heterocycles are one of the most common structural motifs in approximately 80% of the marketed drugs. Of these, benzimidazoles analogues are known to elicit a wide spectrum of pharmaceutical activities such as anticancer, antibacterial, antiparasitic, antiviral, antifungal as well as chemosensor effect. Based on the benzimidazole core fused heterocyclic compounds, crescent-shaped bisbenzimidazoles were developed which provided an early breakthrough in the sequence-specific DNA recognition. Over the years, a number of functional variations in the bisbenzimidazole core have led to the emergence of their unique properties and established them as versatile ligands against several classes of pathogens. The present review provides an overview of diverse pharmacological activities of the bisbenzimidazole analogues in the past decade with a brief account of its development through the years.


The essays collected in this book represent recent advances in our understanding of speech acts-actions like asserting, asking, and commanding that speakers perform when producing an utterance. The study of speech acts spans disciplines, and embraces both the theoretical and scientific concerns proper to linguistics and philosophy as well as the normative questions that speech acts raise for our politics, our societies, and our ethical lives generally. It is the goal of this book to reflect the diversity of current thinking on speech acts as well as to bring these conversations together, so that they may better inform one another. Topics explored in this book include the relationship between sentence grammar and speech act potential; the fate of traditional frameworks in speech act theory, such as the content-force distinction and the taxonomy of speech acts; and the ways in which speech act theory can illuminate the dynamics of hostile and harmful speech. The book takes stock of well over a half century of thinking about speech acts, bringing this classicwork in linewith recent developments in semantics and pragmatics, and pointing the way forward to further debate and research.


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