Modern Synthesis Research Articles

Post-postmodern Theories, Modernism Redux and the Post-Postmodern Framework

Since the 1990s, postmodernism has undergone the distinctively visible changes in the face of globalization and digital technology, as some theorists and critics claim that postmodernism is dead. Consequently, they have proposed many post-postmodern theories on this issue: remodernism, neomodernism, trans-postmodernism, performatism, altermodernism, digimodernism, metamodernism, transmodernism, and post-postmodernism not as a comprehensive term but as a cultural theory. As revealed from the rise and development of post-postmodern theories, they emerge as a result of the return to modernism. Therefore, modernism redux is examined to discover how it interacts with postmodernism in each theory: the return to modernism; and the integration or synthesis of modernism and postmodernism. In this context, metanarratives, one of the modern attributes, work as a common factor in the post-postmodern theories. From this study in terms of metanarratives, the post-postmodern framework, while echoing Charles Jencks’s critical modernism and Philip Galanter’s complexism, is expected to reach the goal of unveiling how the modern and postmodern attributes are integrated and synthesized into a new cultural entity on a new dimensional stage through interaction at the time of a paradigm shift. In consequence, the post-postmodern framework is revealed as an evolutionary system where the modern and postmodern attributes operate to create post-postmodernism, a new cultural environment. In addition, this mechanism of evolutionary process within the post-postmodern framework will continue to shape the cultural sensibilities years to come.

Evo-Devo Path as a Bridge between Evolution, Morphological Disparity, and Medicine with Comments on “Hopeful Monsters” in the Age of Genomics

Since its inception in the late 1970s/early 1980s, Evolutionary Developmental Biology (Evo-Devo) has produced much insight into the evolution of organismal design. Despite the obvious roots connecting Evo-Devo studies to pathology, malformations have been ignored as possible adaptive phenotypes within a different ecological or phylogenetic context and may provide insight into studies of macroevolution. While early opponents of the Modern Synthesis such as Richard Goldschmidt rooted for “hopeful monsters,” this idea was poorly supported and until recently has gone without many examples. Evo-Devo Path [1, 2] builds upon the theoretical framework of early biologists like Pere Alberch while also bridging our current understanding of genomics and development with the hierarchical organization of pathologies established by Isidore Gregory Saint-Hilaire and morphological disparity, thus further challenging the Modern Synthesis and interrupting the boundary between disease and novelty and serving as a bridge between the fields of biomedical research and natural history. Mutations in the regulation and expression of genes within our genome recur as categorizable malformations through the perturbation of key signaling pathways. With the advent of Evo-Devo and genomic advancements over the last few decades, we are able to revisit the micro-evolutionary-centered Modern Synthesis and the idea of “hopeful monsters” to find that unlike the contentious aura which surrounded Goldschmidt’s work, we may now be in a position to re-examine his theoretical framework along with the tenets of the modern synthesis.

On the problem of biological form.

Embryonic development, which inspired the first theories of biological form, was eventually excluded from the conceptual framework of the Modern Synthesis as irrelevant. A major question during the last decades has centred on understanding whether new advances in developmental biology are compatible with the standard view or whether they compel a new theory. Here, I argue that the answer to this question depends on which concept of morphogenesis is held. Morphogenesis can be conceived as (1) a chemically driven or (2) a mechanically driven process. According to the first option, genetic regulatory networks drive morphogenesis. According to the second, morphogenesis results from an invariant tendency of embryonic tissues to restore changes in mechanical stress. While chemically driven morphogenesis allows an extension of the standard view, mechanically driven morphogenesis would deeply transform it. Which of these hypotheses has wider explanatory power is unknown. At present, the problem of biological form remains unsolved.

Evolutionary Teratology and the Path to Break Through the Mould of the Synthesis Paradigm

The recent introduction of evolutionary teratology has led to the diagnosis of certain anatomical features as developmental anomalies integrated into phylogenies. This approach is part of a broader theoretical restructuring. The application of evolutionary teratology to the forelimbs of non-avian theropod dinosaurs has focused on the drastic forelimbs shortening and manual anomalies of some representatives, both in Ceratosauria and Tetanurae. Evolutionary teratological diagnosis can also be made during post-natal growth, differentiating juvenile and adult stages. The methods of evolutionary teratology and its scales of discussion highlight the need to redefine certain Darwinian notions, leading to consider evo-devo as a connection between disciplines. This aspect is unconsciously reflected by calls for various inclusions within a modern synthesis evolving towards an evolutionary extended synthesis. However, this step cannot be an end in itself, as the paradigm of synthesis is carrying Darwinian functional defects. Pluralism is an alternative way to overcome these imbalances, implying cultural restructurings.

Claisen-Schmidt, aza-Michael, cyclization via cascade strategy toward microwave promoted synthesis of imidazo[2,1-b]quinazolines

Imidazole blended quinazolines are having a wide run of potential applications in synthetic field. In this current investigation, we reported a modern synthesis with the help of non-conventional energy. Optimization parameters have been stabilized utilizing RSM (Response Surface Method) as well as Taguchi models. The yield obtained from the proposed protocol is significantly higher compared to other routine strategies. The products were explored by implies of 1H, 13C-NMR and HR-MS investigation. Interestingly, cyclization & aromatization has been influenced by KOH in a greater extent. It is critical that the imidazo[1,2-b]quinazolines show intense fluorescence emission, significant stokes shift, and high quantum yield.

A dual light-driven palladium catalyst: Breaking the barriers in carbonylation reactions.

Transition metal-catalyzed coupling reactions have become one of the most important tools in modern synthesis. However, an inherent limitation to these reactions is the need to balance operations, because the factors that favor bond cleavage via oxidative addition ultimately inhibit bond formation via reductive elimination. Here, we describe an alternative strategy that exploits simple visible-light excitation of palladium to drive both oxidative addition and reductive elimination with low barriers. Palladium-catalyzed carbonylations can thereby proceed under ambient conditions, with challenging aryl or alkyl halides and difficult nucleophiles, and generate valuable carbonyl derivatives such as acid chlorides, esters, amides, or ketones in a now-versatile fashion. Mechanistic studies suggest that concurrent excitation of palladium(0) and palladium(II) intermediates is responsible for this activity.

An updated biomization scheme and vegetation reconstruction based on a synthesis of modern and mid-Holocene pollen data in China

This paper presents an updated Taxa-PFTs-Biome scheme, based on 18 biomes, 30 Plant Functional Types (PFTs) and 590 pollen taxa from 1630 surface pollen sites in China. The biomization results reveal a total of 16 biome types comprising eight new biomes. By comparing the simulated biome types with modern potential vegetation, 80% of the sampling sites were correctly assigned, which is considerably more accurate than studies which have used previous Chinese biomization schemes. The biome reconstruction for the mid-Holocene (6 ± 0.5 14 C kyr B.P.) shows that: (1) In eastern China, tropical, subtropical, warm-temperate and cool-temperate forests did not significantly expand northward, whilst cold-temperate forests were absent from northeastern China; and (2) in central China, the western boundary of steppe vegetation was shifted westwards due to a ~150–300 km extension of the forest and forest-steppe biomes, which is close to the present-day 200–300 mm isohyet. The northwestward shift of the forest and forest-steppe in central China during the mid-Holocene indicates that moisture levels were enhanced compared to the present day. The climatic mechanism responsible was likely a strengthened East Asian summer monsoon, which resulted in increased moisture transport from the ocean to the semiarid regions in northern China, promoting the development of forest and forest-steppe vegetation. • An updated taxa-PFTs-Biome scheme, based on 1630 surface pollen sites in China, was established. • The average accuracy of the updated scheme is more than 80%, which higher than previous Chinese schemes. • The boundary of the forest-steppe zone during mid-Holocene generally advanced northwestwards by about 200-300 km.

Sustainable and Efficient Route for the Regeneration of Carbonyl Compounds from Oximes Using Aqueous Extract of Sapindus laurifolia under Microwave Radiation.

The synthesis of organic compounds using aqueous medium has become an indispensable tool for modern chemical synthesis strategies because of its ability to produce pure products with higher yield at ambient temperature. The conversion of oxime group into carbonyl group serves as a key step for several organic syntheses. This article describes the regeneration of carbonyl compounds from the oxime group present in various carbon skeletons using I2 and aqueous extract of Sapindus laurifolia under microwave radiation. A correlation has been established between the critical micellar concentration of saponin extracted from Sapindous laurifolia and the yield percentage of regenerated different carbonyl compounds. An effortless, competent, and environmentally compassionate protocol for the regeneration of carbonyl compound with a high percent of yield in the range 45–95% could be achieved.

Engaging α-Fluorocarboxylic Acids Directly in Decarboxylative C–C Bond Formation

Fluorine-containing organic molecules, particularly those that bear (sp3)C–F bonds, are rapidly gaining prominence in modern chemical synthesis. Although extensive studies have been devoted to the ...

The Cascade C─H functionalization with sequential hydroxylation and oxidation through heterogeneous BINAP‐copper on hydrotalcite

AbstractBACKGROUNDAromatic thioether derivatives exist widely in natural products and have significant applications in modern synthesis and the pharmaceutical industry; for example, 2‐sulfanylphenols and arylthioquinones are important intermediates in the processing of anticancer, antibiotic, antivirus and antimalarial drugs. Direct C─H hydroxylation was considered as one of the efficient methods for the synthesis of these compounds. Homogeneous transition metal catalysts usually were used through a cross‐coupling of halogen‐substituted phenols with thiophenols. However, from the perspectives of sustainable development and easy recovery, it is necessary to develop an efficient and recoverable catalytic system to realize the synthesis of aromatic thioether derivatives with good efficiency and recyclability.RESULTSThe heterogeneous catalyst [Cu(binap)I]2@HT in the present work showed good catalytic activity for the C─H hydroxylation of benzenethiol and phenylboronic acid. The catalytic system was tolerant to various substituents including alkyl, alkoxy, ester, halogen or trifluoromethyl on the phenyl ring of the thiophenols or arylboric acids. In addition to electron‐donating groups, the products with strong electron‐withdrawing groups, such as methyl formylate and trifluoromethyl also were achieved with good yields at 90 °C for 12 h (68% and 66%, respectively). Repeated experiment results showed that the catalyst could be reused at least five times without obvious decrease in catalytic activity.CONCLUSIONA BINAP‐Cu complex supported on hydrotalcite was prepared and used as a heterogeneous catalyst for the C─H activation of thiophenol under mild reaction conditions. Through a cascade C─H hydroxylation and further oxidation process, 2‐Sulfanylphenols and arylthioquinones could be obtained with moderate‐to‐good yields for a series of 2‐(phenylthio)phenol derivatives using the heterogeneous catalyst [Cu(binap)I]2@HT. In addition, this heterogeneous catalyst showed good recylbility. © 2020 Society of Chemical Industry

Toccata and toccata style in Yurii Reshetar’s piano works

Toccata and toccata style in Yurii Reshetar’s piano works

Unified Extracted Pole Filter Synthesis: Bridging the Gap Between EM and Circuit Simulations

This article reviews the three key concepts of modern microwave-filter synthesis using coupled resonators: coupling matrix (CM), extracted pole (EP), and nonresonating node (NRN). CM synthesis is no doubt the most popular and powerful of the three. EP has been around longer as a circuit-synthesis tool, but it seems to have only limited applications. Both CM and EP were developed before the proliferation of electromagnetic (EM) simulators and fast modern computers. CM is widely used because the simple mapping relationship between the physical dimension of coupling structures and synthesized coupling values is well developed. NRN is the newest concept and has drawn a lot of attention. It is a result of circuit synthesis but can also be expressed using CM/EP.

Copper-catalysed benzylic C-H coupling with alcohols via radical relay enabled by redox buffering.

Cross-coupling reactions enable rapid, convergent synthesis of diverse molecules and provide the foundation for modern chemical synthesis. The most widely used methods employ sp2-hybridized coupling partners, such as aryl halides or related pre-functionalized substrates. Here, we demonstrate copper-catalysed oxidative cross coupling of benzylic C–H bonds with alcohols to afford benzyl ethers, enabled by a redox-buffering strategy that maintains the activity of the copper catalyst throughout the reaction. The reactions employ the C–H substrate as the limiting reagent and exhibit broad scope with respect to both coupling partners. This approach to direct site-selective functionalization of C(sp3)–H bonds provides the basis for efficient three-dimensional diversification of organic molecules and should find widespread utility in organic synthesis, particularly for medicinal chemistry applications.

Beyond the modern synthesis: A framework for a more inclusive biological synthesis

Many theorists in recent years have been calling for evolutionary biology to move beyond the Modern Synthesis – the paradigm that has long provided the theoretical backbone for the discipline. Terms like “postmodern synthesis,” “integrative synthesis,” and “extended evolutionary synthesis” have been invoked by various critics in connection with the many recent developments that pose deep challenges – even contradictions – to the traditional model and underscore the need for an update, or a makeover. However, none of these critics, to this author’s knowledge, has to date offered an explicit alternative that could provide a unifying theoretical paradigm for our vastly increased knowledge about living systems and the history of life on Earth (but see Noble 2015, 2017). This paper briefly summarizes the case against the Modern Synthesis and its many amendments over the years, and a new paradigm is proposed, called an “Inclusive Biological Synthesis,” which, it is argued, can provide a more general framework for the biological sciences. The focus of this framework is the fundamental nature of life as a contingent dynamic process – an always at-risk “survival enterprise.” The ongoing, inescapable challenge of earning a living in a given environmental context – biological survival and reproduction – presents an existential problem to which all biological phenomena can be related and comprehended. They and their “parts” can be analyzed in relation to ethologist Niko Tinbergen’s four key questions. Some basic properties and guiding assumptions related to this alternative paradigm are also identified.

Remote Nickel-Catalyzed Cross-Coupling Arylation via Proton-Coupled Electron Transfer-Enabled C-C Bond Cleavage.

Cross-coupling reactions for carbon-carbon and carbon-heteroatom bond formation are of great importance in modern chemical synthesis. In addition to classical cross-couplings involving preformed or preactivated coupling partners, more recently breakthroughs have been made in the selective, direct coupling of abundant aliphatic carbon-hydrogen bonds using hydrogen atom transfer reactions in which the bond-dissociation energy is the thermodynamic driving force. The more challenging carbon-carbon bond activation is still rather underdeveloped due to the bond inertness. Herein, we report a mild and general strategy for the activation of a diverse set of readily available cyclic alcohols for the remote and site-specific arylation of ketones via the combination of photoredox-mediated multisite concerted proton-electron transfer (MS-PCET) and nickel catalysis. The current cross-coupling proceeds with the generation of an alkoxy radical utilizing bond-dissociation free energy (BDFE) as the thermodynamic driving force. Subsequently, the resulting remote carbon-centered radicals formed by C-C cleavage merge with the nickel catalytic cycle to create the challenging C(sp3)-C(sp2) bonds.

Conflation and refutation: Book Review of Uller, T. and K. N. Laland. eds. 2019. Evolutionary Causation: Biological and Philosophical Reflections. MIT Press, Cambridge, MA. 352: pp. ISBN: 978‐0‐262‐03992‐5. $60.00/£50.00.

Evolutionary Causation, the new edited book from Tobias Uller and Kevin Laland (Uller and Laland, 2019) should be seen as a positive contribution to those seeking an Extended Evolutionary Synthesis (EES). The ambition for an EES has emerged most vociferously over the past 15 years, but its antecedents stretch back to the key work in the 1970s of Gould, Lewontin and their colleagues. At root arguments for an EES are arguments about how the Modern Synthesis (MS) in evolutionary biology has been found wanting. Much of this discontent has been to do with theoreticians rethinking concepts of adaptation, inheritance and development (Jablonka and Lamb, 2006; Huneman and Walsh, 2017) as well as variation and macroevolution (Pigliucci and Muller, 2010). This book continues this work, but focuses on analysis of the central concept of causation within evolution.

Synthesis of biaryl ketones by arylation of Weinreb amides with functionalized Grignard reagents under thermodynamic control vs. kinetic control of N,N-Boc2-amides.

A highly efficient method for chemoselective synthesis of biaryl ketones by arylation of Weinreb amides (N-methoxy-N-methylamides) with functionalized Grignard reagents is reported. This protocol offers rapid entry to functionalized biaryl ketones after Mg/halide exchange with i-PrMgCl·LiCl under operationally-simple and practical reaction conditions. The scope of the method is highlighted in >40 examples, including bioactive compounds and pharmaceutical derivatives. Collectively, this transition-metal-free approach offers a major advantage over the recently established cross-coupling of amides by oxidative addition of N-C(O) bonds. Considering the utility of amide acylation reactions in modern synthesis, we expect that this method will be of broad interest.

Survival of the cheapest: how proteome cost minimization drives evolution.

Darwin's theory of evolution emphasized that positive selection of functional proficiency provides the fitness that ultimately determines the structure of life, a view that has dominated biochemical thinking of enzymes as perfectly optimized for their specific functions. The 20th-century modern synthesis, structural biology, and the central dogma explained the machinery of evolution, and nearly neutral theory explained how selection competes with random fixation dynamics that produce molecular clocks essential e.g. for dating evolutionary histories. However, quantitative proteomics revealed that selection pressures not relating to optimal function play much larger roles than previously thought, acting perhaps most importantly via protein expression levels. This paper first summarizes recent progress in the 21st century toward recovering this universal selection pressure. Then, the paper argues that proteome cost minimization is the dominant, underlying 'non-function' selection pressure controlling most of the evolution of already functionally adapted living systems. A theory of proteome cost minimization is described and argued to have consequences for understanding evolutionary trade-offs, aging, cancer, and neurodegenerative protein-misfolding diseases.

Extending Boolean Methods for Scalable Logic Synthesis

In recent years, Boolean methods in logic synthesis have been drawing the attention of EDA researchers due to the continuous push to advance quality of results. Boolean methods require high computational cost, as they rely on complete functional properties of a logic circuit (e.g., don’t cares), but usually result in better optimization. In particular, Boolean resubstitution is considered one of the most powerful Boolean methods in logic synthesis. In this paper, we present three novel Boolean resubstitution algorithms designed to be scalable and runtime-effective in a modern synthesis flow. They make use of circuit partitioning techniques and Boolean filtering to be fast and computationally tractable. We also discuss different data structures and reasoning engines, namely truth tables, binary decision diagrams, and satisfiability, that are required to gather don’t cares and functional information. As the choice of the engine determines the scalability of Boolean resubstitution we present different scenarios in which the Boolean methods are best driven by one or the other of these. We have implemented the presented resubstitution techniques together with state-of-the-art methods in an industrial logic optimization engine to create a novel resynthesis flow. Our global resynthesis flow achieves significant synthesis results: Within the EPFL synthesis competition, we improve the best-known area results when mapped into LUT-6; when embedded in a commercial EDA flow, the new Boolean resynthesis flow results in 3.12% combinational area savings and 1.34% WNS reduction after physical implementation, at contained (w.r.t. the time of the entire flow) runtime cost.

El ideal de unificación en biología: el caso de la síntesis evolutiva extendida

In this article I will analyze whether the so-called Extended Evolutionary Synthesis (EES) represents a synthesis and an extension with respect to its predecessor, Modern Synthesis (MS). It will be argued that the MS proposes an externalist approach to evolution while the EES considers it necessary to overcome the internalism/externalism dichotomy by proposing more integrative approaches. It will be concluded that the EES cannot be considered an extension of MS and that the appeal to that extension is related to sociological aspects and the epistemic value of theoretical unification that was always present in biological evolutionary thinking.