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Constructing Thioether/Vinyl Sulfide-tethered Helical Peptides Via Photo-induced Thiol-ene/yne Hydrothiolation
Published on: August 1, 2018
Synthesis of orthogonally protected L-threo-beta-ethoxyasparagine
Jan Spengler1, Marta Pelay, Judit Tulla-Puche
1Institute for Research in Biomedicine, Barcelona Science Park, Baldiri Reixac 10, 08028, Barcelona, Spain. jan.spengler@irbbarcelona.org
Abstract:
Orthogonally protected L-threo-beta-ethoxyasparagine (Fmoc-EtOAsn(Trt)-OH, 1) was synthesized from diethyl (2S,3S)-2-azido-3-hydroxysuccinate 2 in eight steps as a building block for solid-phase peptide synthesis. The starting material is easily available in multi-gram scale from D-diethyltartrate. The transformation steps reported here are robust and scalable. Thus, a significant amount of 1 (1.8 g) was obtained in 21% overall yield. The synthesis reported is also expected to be useful for the preparation of other O-substituted L-threo-beta-hydroxyasparagine derivatives.
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