Diastereoselective radical mediated alkylation of a chiral glycolic acid derivative.

Radical alkylation of 2-(tert-butyl)-2-methyldioxolan-4-one, a chiral equivalent of glycolic acid, occurs with good to high diastereoselectivity that compares favorably with the corresponding enolate alkylation. The importance of the position of the transition state position, early or late, is highlighted.

Total syntheses of the actin-binding macrolides latrunculin A, B, C, M, S and 16-epi-latrunculin B.

The latrunculins are highly selective actin-binding marine natural products and as such play an important role as probe molecules for chemical biology. A short, concise and largely catalysis-based approach to this family of bioactive macrolides is presented. Specifically, the macrocyclic skeletons of the targets were forged by ring-closing alkyne metathesis (RCAM) or enyne-yne metathesis of suitable diyne or enyne-yne precursors, respectively.