One of our featured protocols this month is for the partial reduction of electron-deficient pyrroles under both Birch (Li/NH₃) and ammonia-free (Li/DBB) conditions using the formation of pyrrolines 2, 3 and 5 as examples (for reaction scheme click here). Pyrroles 2 and 5 have recently been published by Donohoe et al. as key intermediates in the of the biologically active natural products 1-epiaustraline, hyacinthacine A119and omuralide (also known as lactacystin -lactone).

Besides being an excellent protocol with beautiful photographs of reactions in progress, it is the first of our Nature Protocols to have associated with it two Network Protocols. These are for the preparation of the starting materials 1 and 4, namely the N-Boc pyrrole 2,5-methyl diester and the N-Boc pyrrole 2-ethyl ester.

Our Protocols Network has two components: protocols, such as these, that are uploaded by users (or suppliers); and comments that can be made both on the open access and the peer-reviewed content. If you would also like to participate, by uploading your favourite method or suggesting modifications to those that have already been published, you could follow the links from our homepage. A Guide to Authors for the Protocols Network also contains more information about this part of our content.

Bronwen (Nature Protocols)

References:
1. Donohoe, T.J. et al. Utility of the ammonia-free Birch reduction of electron-deficient pyrroles: total synthesis of the 20S proteasome inhibitor, clasto-lactacystin -lactone. Chem. Eur. J. 11, 4227–4238 (2005).
2. Donohoe, T.J. & Sintim, H.O. A concise total synthesis of ( )-1-epiaustraline. Org. Lett. 6, 2003–2006 (2004).
3. Donohoe, T.J., Sintim, H.O. & Hollinshead, J. A noncarbohydrate based approach to polyhydroxylated pyrrolidizines: total syntheses of the natural products hyacinthacine A1 and 1-epiaustraline. J. Org. Chem. 70, 7297–7304 (2005).
4. Donohoe, T.J., Sintim, H.O., Sisangia, L. & Harling, J.D. An efficient synthesis of lactacystin -lactone. Angew. Chem. Int. Ed. 43, 2293–2296 (2004).

Posted by Bronwen Dekker at 04:47 AM | Permalink | Comments (0) | TrackBacks (0)

[JF - Bronwen Dekker, an Assistant Editor for Nature Protocols has asked me to post this.]

Nature Protocols is a new online journal for the presentation of both new and old methods in a step-by-step/recipe format. Packed full of useful information in the form of CRITICAL STEPs, CAUTIONs and TROUBLESHOOTING tables, these protocols should be a valuable resource for bench researchers. There are two submission routes: protocols that have been commissioned, peer-reviewed and edited will be published in the 'Nature Protocols' section and non peer-reviewed material can be posted as 'Network Protocols.' The content of Nature Protocols will be free until the end of July, but the Network Protocols will always be freely available.

While most of the content at present is geared toward the biological sciences, we think that this will also become a useful resource for synthetic and analytical chemists as it could be a forum where labs can post their methods thus sharing valuable information on how to perform syntheses or analyses of specific classes of compounds. In the moderated commenting facility, other researchers will be able to suggest modifications to the published steps that improve results in their hands. Other functionality includes links to key information, such as articles where the procedure has been used previously and information about relevant reagents and equipment.

Current content includes methods for analyzing proteins using mass spectrometry (for example, for quantifying changes in the abundance of specific proteins by in-gel isotope labeling - Asara et al.), radiolabeling protocols (for example, labeling proteins with indium-111 and yttrium-90 - Cooper et al.), and the synthesis of reagents (for example, the preparation and use of azido ruthenium, a new photoreactive probe for investigating calcium-binding proteins - Israelson et al.).

Bronwen

Bronwen Dekker (Assistant Editor, Nature Protocols)

Posted by Joshua Finkelstein at 02:02 PM | Permalink | Comments (0) | TrackBacks (0)