Haug, Bengt Erik Rich, Daniel H. Synthesis of a Gln-Phe Hydroxy-ethylene Dipeptide Isostere The protected Gln-Phe hydroxyethylene dipeptide isostere <b>1</b> was synthesized as a precursor for preparation of potential inhibitors of Botulinum neurotoxin B metalloprotease. The method allows for the synthesis of additional hydroxyethylene dipeptide isosteres such as <b>2</b> with functionalized P<sub>1</sub> side chains. The isosteres prepared were coupled with a dipeptide to produce protected pseudotetrapeptide derivatives. Botulinum neurotoxin B metalloprotease;functionalized P 1 side chains;hydroxyethylene dipeptide isosteres;pseudotetrapeptide derivatives 2004-12-09
    https://acs.figshare.com/articles/journal_contribution/Synthesis_of_a_Gln_Phe_Hydroxy_ethylene_Dipeptide_Isostere/3312913
10.1021/ol047879y.s001