Synthesis of Dehydro-Dephospho-Fostriecin and Formal Total Synthesis of Fostriecin.

A formal synthesis of fostriecin (1) and a total synthesis of its related congener dihydro-dephospho-fostriecin 2 have been achieved. The route relies upon the use of the Sharpless dihydroxylation to set the absolute stereochemistry at C-8/9 and Noyori transfer hydrogenation and Leighton allylation to set the C-11 and C-5 relative stereochemistry, respectively. Finally, the divergent functionalization of a C-12/13 alkyne was used to establish the Z,E-dienyne of dehydro-dephospho-fostriecin 2 and the Z,Z,E-triene of fostriecin (1).