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Synlett 2012; 23(18): 2643-2646
DOI: 10.1055/s-0032-1317445
DOI: 10.1055/s-0032-1317445
letter
Azide- and Alkyne-Functionalised α- and β3-Amino Acids
Further Information
Publication History
Received: 14 August 2012
Accepted after revision: 20 September 2012
Publication Date:
12 October 2012 (online)
![](https://www.thieme-connect.de/media/synlett/201218/lookinside/thumbnails/10.1055-s-0032-1317445-1.jpg)
Abstract
The synthesis and full characterisation of bifunctional β3-amino acids that have side chains functionalised with terminal azides (S)-4 and (R)-4 or acetylenes 5 and 6 is reported for the first time. The building blocks incorporate a turn-inducing β3-segment and a side chain that can be functionalised further, for example, through copper-catalysed Huisgen cycloaddition. Moreover, the corresponding α-amino acids 1 and 3 have been synthesised and characterised. All amino acid building blocks were of high optical purity as demonstrated by derivatisation and subsequent NMR analysis.
Key words
alkynes - azides - amino acids - diazotransfer - Arndt–Eistert homologation - peptidomimeticsSupporting Information
- for this article is available online at http://www.thieme-connect.com/ejournals/toc/synlett. Included are detailed experimental procedures, 1H and 13C NMR spectra.
- Supporting Information
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References and Notes
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Both enantiomers of amino acid 5 are commercially available from a number of vendors and according to Chemical Abstract (CAS) have been reported in two Chinese papers: