Synlett 2009(5): 720-723  
DOI: 10.1055/s-0028-1087816
LETTER
© Georg Thieme Verlag Stuttgart ˙ New York

Thieme Chemistry Journal Awardees - Where are They Now? Scope of Tyrosine O-Arylations with Boronic Acids: Optimized Synthesis of an Orthogonally Protected Isodityrosine

Bahar Kilitoglua,b, Hans-Dieter Arndt*a,b
a Fakultät Chemie, Technische Universität Dortmund, Otto-Hahn-Str. 6, 44221 Dortmund, Germany
b Abteilung Chemische Biologie, Max-Planck-Institut für Molekulare Physiologie, Otto-Hahn-Str. 11, 44227 Dortmund, Germany
Fax: +49(231)1332424; e-Mail: hans-dieter.arndt@mpi-dortmund.mpg.de;
Further Information

Publication History

Received 10 November 2008
Publication Date:
16 February 2009 (online)

Abstract

The Evans-Chan-Lam variant of the Ullman condensation has been explored to deliver O-arylated tyrosines and tyrosinyl peptides. Key modifications for success were the slow addition of boronic acids to the phenol-catalyst mixture. Selectivity and scope are investigated.

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All peptides were accessed by standard solid-phase peptide synthesis protocols on 2-Cl-trityl or Rink-amide resins, when appropriate, using Fmoc-protected amino acids and HOBt, HBTU, and EtN(i-Pr)2 as coupling reagents.