Morphinane is the parent substance of the broad class of chiral molecules known as the morphine alkaloids. Interestingly, the (+) and (-) enantiomers of the compounds in this family have rather different physiological properties. The (-) compounds, such as morphine, are "narcotic analgesics" (painkillers), whereas the (+) compounds are "antitussives" (ingredients in cough syrup). Dextro-methorphan is one of the simplest and most common of the latter.

(a) Locate and identify all the stereocenters in dextromethorphan.
(b) Draw the enantiomer of dextromethorphan.
(c) As best you can (it is not easy), assign R and S configurations to all the stereocenters in dextromethorphan.

Transcribed Image Text:

CH3O NH NCH3 Morphinane Dextromethorphan