Propranolol is a drug prescribed to treat cardiac arrhythmia and angina pain and to lower...

Propranolol is a drug prescribed to treat cardiac arrhythmia and angina pain and to lower blood pressure. It is chiral, and one enantiomer is responsible for its therapeutic effects. That enantiomer can be synthesized by a process, outlined in the following scheme, in which the first step is a Sharpless epoxidation to give (.S'j-glycidol. What is the configuration of the propranolol formed by this sequence? (No rearrangements occur.) A bond of the type means unspecified stereochemistry.