Studies toward a synthesis of epothilone A: use of hydropyran templates for the management of acyclic stereochemical relationships

The power of hydropyran matrices in addressing problems associated with the management of stereochemistry in acyclic intermediates was illustrated in the identification of a compound as a synthetic intermediate. Two routes were used for the synthesis of the compound. The first proceeds with the known aldehyde and involves such processes as homologation, cyclocondensation, Luche reduction, mesylation, deprotection and cyclization. The other route involves cyclocondensation and Emmons condensation.