Synthesis of Enantiopure 1,2-Diaminobicyclo[2.2.2]octane Derivatives, C 1 -Symmetric Chiral 1,2-Diamines with a Rigid Bicyclic Backbone

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C 1 -Symmetric 1,2-Diaminobicyclo[2.2.2]octane Ligands in Copper-Catalyzed Asymmetric Henry Reaction: Catalyst Development and DFT Studies

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An Organocatalytic and Stereoselective Vinylogous Domino Process Towards Thiochromans

International audienceA highly diastereoselective organocatalyzed domino Vinylogous sulfa-Michael-Aldol-Cyclocondensation (VMAC) reaction has been developed using alkylidene Meldrum’s acid as dienes highlighting two vinylogous steps, an unprecedented sulfa-1,6-conjugate addition and a diastereoselective aldol reaction triggering a formal (4+2) cycloaddition. This work opens a new route to bio-relevant and original tricyclic thiochroman derivatives

N-Pyrrolidine-based alpha/beta-peptides incorporating ABOC, a constrained bicyclic beta-amino acid, for asymmetric aldol reaction catalysis

International audienceA series of N-pyrrolidine-based alpha,beta-peptide catalysts incorporating a constrained 2-aminobicyclo[2.2.2] octane carboxylic acid (ABOC) residue were synthesized and evaluated in the asymmetric aldol reaction from acetone and some p-substituted benzaldehydes. Their catalytic properties were shown to be highly dependent on the amino acid sequences and on the absolute configuration of the ABOC residue that played a determinant role. Among the peptides tested, the heterochiral tripeptide H-Pro-(R)-ABOC-Asp-OCH3 13, that adopts a turn conformation in the solid state, proved to be the most efficient catalyst affording beta-hydroxy ketones in high yields and good enantioselectivities (up to 87%)

Synthesis, Characterisation and Cytotoxic Activity Evaluation of New Metalsalen Complexes Based on the 1,2-bicyclo[2.2.2]octane Bridge

Diaminobicyclo[2.2.2]octane was used as starting material for the preparation, in solution or in a ball-mill, of a salen ligand. Five metal salen complexes were prepared in high yield and their cytotoxic activities were evaluated against HCT116 cell lines. Original manganese salen complex displayed the highest activity with a potency 16 fold higher than the one of cisplatin, demonstrating the benefit of the bridging backbone, compared to other salen systems. An alternative preparation route for this complex by mechanochemistry was also performed.<br /

Synthesis, characterisation and cytotoxic activity evaluation of new metal-salen complexes based on the 1,2-bicyclo[2.2.2]octane bridge

International audience(R)-1,2-Diaminobicyclo[2.2.2]octane was used as a starting material for the preparation, in solution or in a ball mill, of a salen ligand. Five metal salen complexes were prepared in high yield and their cytotoxic activities were evaluated against the Human Colon cancer HCT116 cell lines. The original manganese salen complex displayed the highest activity with a potency 16 fold higher than that of cisplatin, demonstrating the benefit of the bridging backbone compared to other salen systems. An alternative preparation route for this complex by mechanochemistry was also performed

A bicyclic unit reversal to stabilize the 12/14-helix in mixed homochiral oligoureas

International audienceThe insertion of cyclic building blocks in oligoureas to stabilize or modulate the properties of the 12/14-helix was often fruitless. We herein propose a fully compatible highly constrained building block that could be incorporated into oligoureas to develop highly stable and functionnal oligoureas helices