Problems and exercisesEpothilone
Exercise 1
In the retrosynthesis of epothilone A, why is the epoxide introduced at the end, by epoxidation of epothilone C, rather than carried from the start in a fragment?
Exercise 2
Count the stereocentres of epothilone A. If each were formed without control (1:1 mixture), what fraction of the product would be the natural stereoisomer? What does that teach about planning?