<unk>  has two chiral centers. Thus, four stereoisomers may exist, the (R,R)-, (S,S)-, (R,S)-, and (S,R)-isomers. The active ingredient of<unk>  is a racemic mixture of two enantiomers, the (R,R)-(–)- and (S,S)-(+)-isomer.
Reboxetine
Fluoxetine
Dapoxetine
Duloxetine
Paroxetine
Atomoxetine
Nabilone
Vinpocetine