title: A straightforward route to enantiopure alpha-substituted derivatives of (2S,3aS,7aS)-octahydroindole-2-carboxylic acid.
abstract: High yielding and remarkably selective alkylations of a suitably protected derivative of (2S,3aS,7aS)-octahydroindole-2-carboxylic acid are described. The fused bicyclic structure of this proline analogue greatly influences the stereochemical outcome of direct alkylation reactions taking place at the alpha-carbon and provides access to alpha-substituted analogues with retention of the configuration. The overall procedure allows the preparation of enantiopure alpha-substituted derivatives of this Oic isomer, suitably protected for their incorporation into peptides, in a straightforward manner.
authors.affiliation: Departamento de Química Orgánica, Instituto de Ciencia de Materiales de Aragón, Universidad de Zaragoza-CSIC, 50009 Zaragoza, Spain.
authors.forename: Francisco J
authors.initials: FJ
authors.lastname: Sayago
authors.forename: M Isabel
authors.initials: MI
authors.lastname: Calaza
authors.forename: Ana I
authors.initials: AI
authors.lastname: Jiménez
authors.forename: Carlos
authors.initials: C
authors.lastname: Cativiela