Synthesis 2011(5): 807-815  
DOI: 10.1055/s-0030-1258425
PAPER
© Georg Thieme Verlag Stuttgart ˙ New York

Expedient Synthesis of 1,3-Substituted Benzene Peptidomimetics

Anders Bach, Kristian Strømgaard*
Department of Medicinal Chemistry, The Faculty of Pharmaceutical Sciences, University of Copenhagen, Universitetsparken 2, 2100 Copenhagen, Denmark
Fax: +4535336041; e-Mail: krst@farma.ku.dk;
Further Information

Publication History

Received 8 December 2010
Publication Date:
08 February 2011 (online)

Abstract

A synthetic route for replacing the central amino acid in the tripeptide Thr-Ala-Val (TAV) with a 1,3-substituted benzene ring was developed. l-Threonine was introduced into the benzene ring by a Grignard reaction with protected l-threoninal, where the nature of the side-chain protecting group was found to be of utmost importance. Subsequently, l-valine was introduced by a copper-mediated amination. Overall, the tripeptide analogue was obtained in six steps with an overall yield of 18%. An orthogonal protecting group strategy allowed attachment of the tripeptide analogue to a solid support and subsequent preparation of the corresponding pentapeptide analogue. Both compounds were tested in a plasma stability assay, showing improved stability compared to their peptide counterparts.