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Synlett 2013; 24(5): 591-594
DOI: 10.1055/s-0032-1318316
DOI: 10.1055/s-0032-1318316
letter
A Facile, Inexpensive and Scalable Route to Thiol-Protected α-Methyl Cysteine
Further Information
Publication History
Received: 22 January 2013
Accepted: 06 February 2013
Publication Date:
25 February 2013 (online)
![](https://www.thieme-connect.de/media/synlett/201305/lookinside/thumbnails/10.1055-s-0032-1318316-1.jpg)
Abstract
A facile, scalable synthesis of α-methyl cysteine with three alternate thiol protecting groups (trityl, allyl and tert-butyl) is described. The thiol-protected amino acids are obtained in six steps from l-cysteine ethyl ester and are ideally suited for a range of natural product and solid-phase peptide synthesis applications.
Key words
natural products - α-methyl cysteine - solid-phase peptide synthesis - camphorsultam auxiliary - P2-EtSupporting Information
- for this article is available online at http://www.thieme-connect.com/ejournals/toc/synlett. Included are the preparation of α-methyl cysteine 10, and 1H NMR and 13C NMR spectra for all compounds.
- Supporting Information
-
References and Notes
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For selected examples of RCM peptide stapling with the α-methyl all-carbon homologue, see:
For examples of Grubbs II catalysed RCM macrocyclisation using S-allyl cysteine derivatives, see: