Cyclotryptophan Mycotoxins: Short Synthesis of the Desymmetrized meso-Chimonantine Core of Leptosin C

The desymmetrized meso-chimonantine core of leptosin C was prepared in a short stereoselective convergent sequence in 5 steps as the longest linear path from methyl l-tryptophan hydrochloride as starting material. The key step of this approach was a diastereoselective [4+2] cycloaddition between the bromooxindole and tryptophan derivatives allowing to define the adjacent quaternary benzylic centers in a high chemical yield

Synthese d'analogues carbocycliques du N-acetyl Muramyl-dipeptide (MDP) et du lipide X (LPX) : immunomodulateurs potentiels

SIGLECNRS T Bordereau / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Enantioselective organocatalysis: reactions and experimental procedures

In this reference leaders at the forefront of research provide an insight into one of the hottest topics in organic synthesis, focusing on the most important enantioselective reactions.Clearly structured, each entry begins with a concise introduction, including a mechanistic discussion of the reaction, followed by preparative guidelines for newcomers, such as carefully selected working procedures with critical notes for bench chemists, rules of thumb and tips and tricks

Do We Need Asymmetric Organocatalysis?

Asymmetric organocatalysis is a 'fast lane' of the chemical highway: the progress in the last decade is simply spectacular. This introductory article summarizes basic principles, historical background, and discusses basic catalyst classes and reaction types

Organocatalytic Radical and Electron Transfer Reactions

International audienceOpen shell (radical and radical ionic) reactions are distinguished by complementary chemoselectivity compared to ionic (closed‐shell) reactions. Conditions for synthetically useful asymmetric intra‐ and intermolecular α‐alkylation, allylation, arylation, fluoroalkylation, and heteroatom functionalization of carbonyl compounds have emerged via electron‐transfer mediated reactions, including oxidative conditions, redox photoreactions, and purely photochemical approaches

From One-Photon to Two-Photon Probes: “Caged” Compounds, Actuators, and Photoswitches

International audienceMolecular systems that can be remotely controlled by light are gaining increasing importance in cell biology, physiology, and neurosciences because of the spatial and temporal precision that is achievable with laser microscopy. Two‐photon excitation has significant advantages deep in biological tissues, but raises problems in the design of “smart” probes compatible with cell physiology. This Review discusses the chemical challenges in generating suitable two‐photon probes

Die "Innige Seele" in einer Mainzer Handschrift

Übersehen wurde bislang, dass die "Innige Seele" aus der Gruppe der Dialoggedichte "Kreuztragende Minne" in der Handschrift der Stadtbibliothek Mainz Hs I 327 überliefert ist und von FWE Roth abgedruckt wurde. Das lange vermisste Tafelgemälde aus der Klause Kamp gegenüber von Boppard befindet sich heute in der Sammlung Thyssen-Bornemisza in Madrid. Ferdinand Wilhelm Emil Roth, Mittheilungen aus Handschriften und älteren Druckwerken. In: Zeitschrift für deutsche Philologie 26 (1894), S. 58-70,..