The synthesis of the four stereoisomers of carbon-11 labeled meta-hydroxyephedrine (HED) and meta-hydroxypseudoephedrine (HPED) was undertaken for evaluation of their in vivo kinetic behavior. The stereoisomers of HED and HPED were synthesized by conversion of their respective enantiomerically-pure, normethyl precursors (meta-hydroxyphenylpropanolamine stereoisomers) to the carbamate derivatives and