title: Bifunctional Chiral Dehydroalanines for Peptide Coupling and Stereoselective S-Michael Addition.
abstract: A second generation of chiral bicyclic dehydroalanines easily accessible from serine has been developed. These scaffolds behaved as excellent S-Michael acceptors when tri-O-acetyl-2-acetamido-2-deoxy-1-thio-α-d-galactopyranose (abbreviated as GalNAc-α-SH) was used as a nucleophile. This addition proceeds with total chemo- and stereoselectivity, complete atom economy, quickly, and at room temperature, making it a true click reaction. The Michael adducts were easily transformed into S-(2-acetamido-2-deoxy-α-d-galactopyranosyl)-l- and -d-cysteines, which can be regarded as mimics of the Tn antigen derived from l-Ser (α-d-GalNAc-l-Ser) and d-Ser (α-d-GalNAc-d-Ser), respectively.
authors.affiliation: Departamento de Química, Universidad de La Rioja, Centro de Investigación en Síntesis Química , E-26006 Logroño, Spain.
authors.forename: Marta I
authors.initials: MI
authors.lastname: Gutiérrez-Jiménez
authors.affiliation: CECB, Department of Chemistry, University of Copenhagen , Universitetsparken 5, 2100 Copenhagen, Denmark.
authors.forename: Carlos
authors.initials: C
authors.lastname: Aydillo
authors.affiliation: Departamento de Química, Universidad de La Rioja, Centro de Investigación en Síntesis Química , E-26006 Logroño, Spain.
authors.forename: Claudio D
authors.initials: CD
authors.lastname: Navo
authors.affiliation: Departamento de Química, Universidad de La Rioja, Centro de Investigación en Síntesis Química , E-26006 Logroño, Spain.
authors.forename: Alberto
authors.initials: A
authors.lastname: Avenoza
authors.affiliation: Departamento de Química, Universidad de La Rioja, Centro de Investigación en Síntesis Química , E-26006 Logroño, Spain.
authors.forename: Francisco
authors.initials: F
authors.lastname: Corzana
authors.affiliation: Departamento de Química, Universidad de La Rioja, Centro de Investigación en Síntesis Química , E-26006 Logroño, Spain.|Institute of Biocomputation and Physics of Complex Systems (BIFI), University of Zaragoza, BIFI-IQFR (CSIC) , 50018 Zaragoza, Spain.
authors.forename: Gonzalo
authors.initials: G
authors.lastname: Jiménez-Osés
authors.affiliation: Departamento de Química, Universidad de La Rioja, Centro de Investigación en Síntesis Química , E-26006 Logroño, Spain.
authors.forename: María M
authors.initials: MM
authors.lastname: Zurbano
authors.affiliation: Departamento de Química, Universidad de La Rioja, Centro de Investigación en Síntesis Química , E-26006 Logroño, Spain.
authors.forename: Jesús H
authors.initials: JH
authors.lastname: Busto
authors.affiliation: Departamento de Química, Universidad de La Rioja, Centro de Investigación en Síntesis Química , E-26006 Logroño, Spain.
authors.forename: Jesús M
authors.initials: JM
authors.lastname: Peregrina