Exceptionally High Felkin-Anh Control for the Addition of Nucleophiles to a β-Amino-cyclo-propylcarbaldehyde

Exceptionally high diastereocontrol in agreement with the Felkin-Anh model was observed for the addition of nucleophiles to the β-aminocyclopropylcarbaldehyde 5 in nitroaldol, cyanohydrin, Mukaiyama aldol, and Sakurai reactions, contrasting the low diastereoselectivities generally observed in additions to cyclopropylcarbaldehydes

Novel Strategies for the Synthesis of Peptides containing Cis- or Trans-β-Aminocyclopropyl Carboxylic Acids

The scope and limitation of a new in situ coupling strategy is described, which allows the incorporation of cis- or trans-β-aminocyclopropanecarboxylic acids into peptides

Ozonolysis of Dihydropyrroles and Tetrahydropyridines: A New Strategy to b- and g-Amino Esters and Amino Aldehydes

Upon ozonolysis of 2,3-dihydropyrroles 1a-e and 1,2,3,4-tetrahydropyridines 1f-j, either β- and γ-amino esters or amino aldehydes may be obtained in high yields; the scope and limitations of this approach are discussed. Through utilization of this methodology, an effective synthesis of various 2-aminocyclopropanecarboxylic acid derivatives (β- and γ-analogs of ACC) has been achieved

Evaluation of the Duopath Legionella Lateral Flow Assay for Identification of Legionella pneumophila and Legionella Species Culture Isolates

Duopath Legionella (Merck KGaA, Darmstadt, Germany) is a new immunochromatographic assay for the simultaneous identification of cultured L. pneumophila and Legionella species other than L. pneumophila. In tests of 89 L. pneumophila strains and 87 Legionella strains other than L. pneumophila representing 41 different species, Duopath and a widely used latex agglutination assay detected L. pneumophila with 100% and 98% accuracy, respectively, whereas the percentages differed significantly for other Legionella spp. (93% versus 37% [P < 0.001]). Since many countries’ regulations require the identification of Legionella spp. in water and environmental samples, the use of Duopath Legionella to comply with those regulations could contribute to significantly fewer false-negative results

The Synthesis of Diastereo- and Enantiomerically Pure β-Aminocyclopropane Carboxylic Acids.

The synthesis of diastereo- and enantiomerically pure -aminocyclopropanecarboxylic acids (-ACCs) is described. Starting from pyrrole, (rac)-4 is readily obtained, which was kinetically resolved by enzymatic hydrolysis. Subsequent oxidation of (-)-4 and deformylation gives rise to the cis--ACC derivative (ent)-9, while (+)-10 was converted to the trans--ACC derivative 8. Both 8 and (ent)-9 and their benzyl esters 13 and 16, being conformationally restricted -alanine or -aminobutyric acid (GABA) derivatives, represent useful building blocks for peptides containing unnatural amino acids

A New Strategy for the Stereoselective Synthesis of 1,2,3-trisubstituted Cyclopropanes

The stereoselective synthesis of highly functionalized 1,2,3-trisubstituted cyclopropanes 1 and 2, starting from readily available furans 3 or N-protected pyrrole 4, is described. Furthermore, exceptionally high diastereocontrol in agreement with the Felkin-Anh model was observed for the addition of nucleophiles to the title compounds

Analogues of Neuropeptide Y Containing β-Aminocyclopropane-carboxylic Acids are the Shortest Linear Peptides Selective for the Y₁-Receptor

Koglin N, Zorn C, Beumer R, et al. Analogues of neuropeptide Y containing beta-aminocyclopropane carboxylic acids are the shortest linear peptides that are selective for the Y-1 receptor. Angewandte Chemie International Edition. 2003;42(2):202-205

Epistemische Rivalitäten: zum Umgang mit Sonderwissen an den Höfen des 14. Jahrhunderts

An den Höfen der Könige, Päpste, Fürsten und Fürstinnen entwickelte sich im 14. Jahrhundert eine zunehmende Konkurrenz zwischen Vertreterinnen und Vertretern verschiedener Bestände von Sonderwissen. Die Entscheidung, welches Wissen in welcher Form nutzbar war, verlagerte sich von den gelehrten Milieus auf Laien, an den Höfen auf Herrscher und Herrscherinnen und ihr Umfeld. Der offen ausgetragene Wettbewerb machte es erforderlich, die mit dem jeweiligen Wissensbestand verbundenen Geltungsansprüche, seine Gehalte und seinen möglichen Nutzen sowie die Positionen seiner Trägerinnen und Träger zu überprüfen. Die wachsenden epistemischen Rivalitäten liessen daher Wissen reflexiv werden. Diese Prozesse veranschaulicht der Beitrag anhand von Fallstudien zu ausgewählten lateineuropäischen Höfen