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Covering: up to the end of March 2011 [ABSTRACT FROM AUTHOR]

Covering: up to July 2010 [ABSTRACT FROM AUTHOR]

Azole-based cyclic peptides found in ascidians (‘sea squirts’) of the genus Lissoclinum have a high propensity to chelate metal ions. This Highlight summarises the current evidence for marine cyclic peptide–metal congruence, and the structural and stereochemical features in cyclic peptides which seem necessary to facilitate metal complexation. The biological relevance of the metal ions in these associations, including their possible role in the assembly of cyclic peptides in the marine milieu, is also briefly considered. Finally, the synthesis of natural, and some novel non-natural, azole-based cyclic peptides from the cyclooligomerisation and assembly of azole-based amino acids, including in the presence of metal ions, is presented. [ABSTRACT FROM AUTHOR]

The Stille cross-coupling reaction between a vinylcyclopropylstannane and iodobenzene or phenol triflate provides an expedious route to 1,2-phenylvinylcyclopropanes. However, similar coupling reactions using ORTHO-substituted aromatic substrates also lead to butylaromatic products, resulting from competitive sp ?-sp ?coupling reactions. [ABSTRACT FROM AUTHOR]

A silicon-tethered intramolecular radical cyclisation, in tandem with a radical trapping with allyltri-n-butylstannane forms the basis of a new synthetic strategy to the cyclopentane core of the antitumoral antibiotic substance viridenomycin isolated from Streptomyces viridochromogenes and S. gannmycicus. [ABSTRACT FROM AUTHOR]