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Tandem intramolecular Sakurai-aldol reactions provide a concise and highly diastereoselective route to substituted cyclohexenone derivates. A fully intramolecular variant of the Sakurai-aldol reactions that creates four stereocenters, two new C-C bonds, and establishes two new carbocyclic rings is described.

Research has been conducted on the catalytic asymmetric acyl halide-aldehyde cyclocondensation reaction. The implementation of the reaction design is described and the results indicate that the reaction strategy allows to employ differentially substituted organocuprates in the 4-substituted 2-oxetanone ring opening.

Research has been conducted on the beta-lactones. The preparation of the optically active beta-lactones via enzymatic resolution of the racemic 4-substituted-2-oxetanones derived from the acyl halide-aldehyde reactions has been investigated.

In response to the advance of right-wing populism in many Western democracies, political economists have sought explanations for political disaffection in the socioeconomic dislocations wrought by globalization, deindustrialization, and automation. Distrust of institutions and elites has been identified as a consequence of open markets and neoliberal governance. While affirming the public trust as a cornerstone of liberal democracy, this article directs analysis of the contemporary condition to a broader set of uniquely psychosocial and cultural dynamics. We identify sentiments ranging from disillusion to defiance that are now fueling a runaway politics narrowly defined around race, ethnicity, and national identity. We examine the stakes of eroding public trust in historical and theoretical perspective through an analysis of key works of Karl Polanyi, John Maynard Keynes, and E. H. Carr. Drawing parallels to their assessments of the interwar period, we argue that today's resentment politics is not singularly the product of economic hardship or even institutional failure, but emerges also from a breakdown of the social and cultural ties that underpin liberalism—a "delicate order" built in part on sublimated psychosocial understandings of agency and community. Democracy again hangs in the balance. [ABSTRACT FROM AUTHOR]

Several studies are conducted to explain the various different catalytic asymmetric Claisen rearrangements of the unactivated allyl vinyl ethers.

Two camphor lactams capable of generating chiral dienophiles that could promote quaternary carbon formation through Diels-Alder cycloaddition reaction were synthesized. These camphor lactams converted to the corresponding alpha,beta-unsaturated carboximides via Na salt acylation. Additional reactivity studies were conducted to further characterize the properties of chiral auxiliaries.

N-Alkenyl iminium ions is described as enabling tools for three-component [4+2] cycloaddition-iminium ion addition reactions that afford an efficient and versatile synthesis of highly substituted piperidines. This method is used in both target-directed and diversity-oriented synthesis activities.

The utility of cinchona alkaloid-catalyzed cyclocondensations of acid chlorides and [alpha]-amido sulfones as alternatives for catalytic asymmetric Mannich addition reactions is described. The ketene-imine cycloadditions are mechanistically distinct, thus making them useful alternatives for executing Mannich-type C-C bond constructions.

The isomerization-Claisen rearrangement (ICR) reactions of boron-substituted di(allyl) ethers, the properties of the derived beta-boryl aldehydes, and the utility of these species as conduits to Claisen adducts previously inaccessible from the ICR methodology are described. The merging of ICR methodology with ensuing Suzuki cross-coupling reactions will expand the utility of the ICR technology in various synthesis activities.

Asymmetric cinchona alkaloid (cyclohexenone or cyclopentenone)-catalyzed acid chloride-aldehyde cyclocondensation (AAC) reactions applicable to a range of structurally diverse aldehydes are reported. The alkaloid-catalyzed ketene-aldehyde additions, Lewis acid activation of the aldehyde electrophile emerged as an alternative for eliciting the requisite nucleophilicity from the ammonium enolates.

The reactions of acyl halide-aldehyde cyclocondensation (AAC) and bita-lactones are discussed. These reactions features coupled with the array of transformations available to the AAC and beta-lactones portend considerable utility for this reaction technology.

For too long the discipline of political science has ceded research on the dynamics of the national political economy to the field of economics. In this article, we explore the cost of this cession in the context of the public purpose. Following John Kenneth Galbraith, we define the public purpose in terms of its independence from the market economy and the planning system. Political scientists, and especially political theorists, are uniquely qualified to theorize power relations relative to a host of challenges that have emerged in today's rapidly transforming national economies. Galbraith's critique of mainstream economics, coupled with his understanding of power as an inescapable and perpetual dialectical process, provide guidance for theorizations that should attend to rather than deny the contested domain of the public interest and collective good. [ABSTRACT FROM AUTHOR]

The enantioselective total synthesis of (-)-rhazinilam is reported which demonstrates the success of this reaction design using Au(I)-catalyzed pyrrole-allene additions. Asymmetric Au(I)-catalyzed pyrrole additions to enantioenriched allenes afford a unique entry to optical active heterocycles.

The utility of alkaloid-catalyzed acyl halide-aldehyde cyclocondensation (AAC) reactions for the catalytic asymmetric synthesis of extended propionate networks is described. The AAC-based catalytic asymmetric total synthesis of (-)-pironetin provides evidence for its utility in synthesis efforts directed toward polyketide-derived materials.

The integration of a catalytic asymmetric synthesis of di(allyl) ether substrates into an expedient, two-step protocol was reported for realizing asymmetric aliphatic Claisen rearrangements from readily available starting material. The resulting enantioenriched di(allyl) ethers constitute direct progenitors of asymmetric Claisen rearrangements by virtue of isomerization-Claisen rearrangement (ICR) technology, thereby providing a simple two-step sequence to enantioenriched Claisen adducts from easily obtained precursors.

A study aimed at the broad exploitation of claisen-derived alpha-chiral aldehydes in synthesis activities, and developed highly stereoselective Claisen rearrangements from easily prepared di(allyl) ethers. The claisen rearrangements involved catalyzed olefin isomerization to generate the vinyl ether moiety followed by thermal sigmatropic rearrangement to afford syn-2,3-dialkyl-4-pentenal derivatives with high diastereoselectivity.

Laulimalide is a naturally occurring microtubule-stabilizing agent first isolated from the marine sponges Hyattella sp. and Spongia mycofijiensis. A de novo enantioselective total synthesis of (-)-laulimalide is achieved. The synthesis is characterized by extensive use of new reaction methodology derived from asymmetric aldehyde cyclocondensation (AAC) reactions and ensuing transformations of the derived enantioenriched beta-lactones.

Ligand-defined catalysis is described in the context of Lewis acidity expressed in neutral electron-rich aluminium(III) compounds.

A strategy for effecting catalyzed cross aldol reactions using Al(III)-catalyzed cyclocondensations of acyl halides and enolizable aldehydes was described. The reactive Lewis acid-aldehyde complex responsible for mediating the operative (2+2) ketene-aldehyde cycloaddition as the strategic construct for inducing asymmetry during C-C bond formation was identified. Optically-active Al(III)-triamine complex was found to catalyze the condensation of acetylbromide and benzyloxy-acetaldehyde.

The use of organic-soluble Ti(III) complexes as highly efficient catalysts for pinacol homocoupling reaction and the development of ligand-modified catalysts for controlling diastereoselectivity in the reduced coupling of aryl aldehydes was reported. Ligand-modified Ti(III) complexes were found to be effective in catalyzing reductive homocoupling of various carbonyl compounds.

Lanthanide and alkali metal alkoxides and magnesium-bis(sulfonamide) complexes were analyzed using aryl-substituted carboximides. This undertaking seeks to disclose a chiral metal complex that will mediate the enolization and enantioselective electrophilic amination of (El(+)=BocN=NBoc). Results reveal that lanthanide and alkali metal alkoxides are effective catalysts for completing enantioselective enolate amination in simple carboxylate ester synthons.

An enantioselective variant of the Meerwein-Ponndorf-Verley (MPV) reduction which is catalyzed by a chiral samarium(III) complex at ambient temperatures in 2-propanol, is identified. Milder variants of MPV reduction, using trivalent lanthanide catalysts, enhance the use of this reaction for the reduction of ketones. Freshly developed SmI3 and chiral bi- and tri-dentate ligands are used to produce various Sm(III) complexes.

Democracy and the state are two political notions that have come under considerable duress in late modernity. This paper considers a prominent critic of both, Sheldon Wolin. The paper examines three elements that figure in Wolin's analyses of democracy and the modern state in a central way:: community, memory, and the culture of history. A theorisation of these elements can illuminate what is at stake in the articulation of political conceptions that yield communal forms through the constitution of political space. Wolin's analyses of democracy, the state, and modern power can be of help, first, in elucidating the political valences of the three elements themselves; second, in specifying relationships of mutuality among them; and third, in theorising what is at issue in the transposition of these elements from the domestic sphere to the international. The paper speaks mainly to the first and second concerns. A path is explored for thinking what is at stake in the third, namely, locating in and then transposing from the domestic sphere a ''we'' which does not enjoy a precise ontology, but which is nonetheless capable of giving collaborative efforts in world-political spheres another political ground. [ABSTRACT FROM AUTHOR]

Presently, the zebrafish is the only vertebrate model compatible with contemporary paradigms of drug discovery. Zebrafish embryos are amenable to automation necessary for high-throughput chemical screens, and optical transparency makes them potentially suited for image-based screening. However, the lack of tools for automated analysis of complex images presents an obstacle to using the zebrafish as a high-throughput screening model. We have developed an automated system for imaging and analyzing zebrafish embryos in multi-well plates regardless of embryo orientation and without user intervention. Images of fluorescent embryos were acquired on a high-content reader and analyzed using an artificial intelligence-based image analysis method termed Cognition Network Technology (CNT). CNT reliably detected transgenic fluorescent embryos ( Tg(fli1:EGFP) y1) arrayed in 96-well plates and quantified intersegmental blood vessel development in embryos treated with small molecule inhibitors of anigiogenesis. The results demonstrate it is feasible to adapt image-based high-content screening methodology to measure complex whole organism phenotypes. Developmental Dynamics 238:656-663, 2009. © 2009 Wiley-Liss, Inc. [ABSTRACT FROM AUTHOR]

'The political' is much talked about today, but its invocation in international political theory is all but entirely dismissed. Yet, moral-ethical articulations do impact theorizing about international life, albeit in a most peculiar and often concealed fashion. In this paper I investigate the modernity of sovereignty in political and international theory and explain why invocations of the moral-ethical are so forcefully liquidated from international relations theory. I examine the constitutive effects of the sovereignty imperative and explain how modern notions of ethics, politics and community are delimited by the need to effect what can be made to count as the pre-political ground of will-formation. A peculiar modernist strategy delimits the imagination of the politically possible in international life. I argue that critique must attend and not dispense with a fundamental paradoxicality (which is transfigured as modernity's very metaphysical embodiment) that structures a distinctively modern manner of reflecting on ethics and community. The paradoxicality is sovereignty. It is accommodated by a liberal politics that works to conceal a restive anxiety of the modern 'condition'. This anxiety is in turn productive of a politics with which we must grapple as we elaborate governance in global life. [ABSTRACT FROM AUTHOR]

Examines the role of Β-lactones in the mediation of ring opening of copper-modified alkyl Grignard reagents. Variations in lactone electrophile; Occurrence of identical bond constructions; Synthesis of enantiomerically Βdisubstituted carboxylic acids.

Review: 242 refs. [ABSTRACT FROM AUTHOR]