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DOI: 10.1055/s-0033-1341236
A Short Synthesis of Partially Protected l- and d-β-Hydroxyenduracididines and a Structurally Simplified Dipeptide Analogue
Publication History
Received: 03 March 2014
Accepted after revision: 26 March 2014
Publication Date:
16 May 2014 (online)
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Abstract
A short synthesis of the C2-epimeric amino acids l- and d-β-hydroxyenduracididine (βhEnd) was developed. Both amino acids are part of the cyclopeptide portion of the mannopeptimycin antibiotics. The synthetic route comprises eight steps starting from Garner’s aldehyde and provides partially protected derivatives in good overall yields. Key steps are a stereodivergent olefination–bishydroxylation sequence and a regioselective guanidine cyclization reaction. In addition, precursor amino acids that contain a protected amino alcohol instead of the cyclic guanidine could be efficiently coupled to provide a structurally simplified analogue of the l-βhEnd-d-βhEnd dipeptide portion of the mannopeptimycin aglycone.
Key words
amino acids - cyclic guanidine - natural products - peptide coupling - stereoselective synthesisSupporting Information
- for this article is available online at http://www.thieme-connect.com/products/ejournals/journal/ 10.1055/s-00000084.
- Supporting Information
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