Aza-beta3-cyclopeptides: a new way of controlling nitrogen chirality. - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Journal of the American Chemical Society Année : 2009

Aza-beta3-cyclopeptides: a new way of controlling nitrogen chirality.

Résumé

Sixteen and 24 membered aza-beta(3)-peptidic macrocycles containing a alpha-hydrazinoacid or a beta(3)-aminoacid were synthesized. The conformation of these pseudopeptides was determined by using NH chemical shift analysis, NH extinction, VT-NMR experiments, and X-ray diffraction. The study shows that a stable conformation is retained between 223 and 413 K. The latter is characterized by an uninterrupted internal H-bond network and a syndiotactic arrangement of the asymmetric centers. It means that the presence of the optically pure residue acts as a conformational lock to select a single enantiomer through the cyclization by controlling the absolute configuration of all the nitrogen atoms. To our knowledge, this represents the first example of a dynamic enantioselection process involving several centers prone to pyramidal inversion. These results give a new impulsion to the control of nitrogen chirality, which remained limited to small cycles for 60 years.

Domaines

Chimie organique
Fichier non déposé

Dates et versions

hal-00432327 , version 1 (16-11-2009)

Identifiants

Citer

Clémence Mocquet, Arnaud Salaün, Paul Claudon, Barbara Le Grel, Michel Potel, et al.. Aza-beta3-cyclopeptides: a new way of controlling nitrogen chirality.. Journal of the American Chemical Society, 2009, 131 (40), pp.14521-5. ⟨10.1021/ja9058074⟩. ⟨hal-00432327⟩
115 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Mastodon Facebook X LinkedIn More