| 21. | The ( + )-enantiomer is the active stereoisomer.
 
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 | 22. | Typically, only a single enantiomer is pharmacologically active.
 
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 | 23. | The term may refer to either of two enantiomers.
 
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 | 24. | Adderall is an unequal mixture of both amphetamine enantiomers.
 
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 | 25. | The S-enantiomer is believed to be the more pharmacologically active enantiomer.
 
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 | 26. | The S-enantiomer is believed to be the more pharmacologically active enantiomer.
 
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 | 27. | The R-enantiomer is converted through a series of three main enzymes.
 
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 | 28. | Again, only the D enantiomer is naturally occurring.
 
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 | 29. | Deprenyl is a racemic compound, a mixture of two isomers called enantiomers.
 
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 | 30. | HU-210 is the enantiomer of HU-211 ( Dexanabinol ).
 
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