Amphetamine

Amphetamine is a synthetic central nervous system stimulant belonging to the phenethylamine and amphetamine classes of compounds.

• IUPAC name:
  (RS)-1-phenylpropan-2-amine
  (also commonly written as α-methylphenethylamine)
• Molecular formula:
  C₉H₁₃N
• Molar mass:
  135.21 g/mol

Chemical class

• Phenethylamine
• Substituted amphetamine
• Monoamine stimulant

Key structural features

• A benzene (phenyl) ring
• A two-carbon ethyl side chain
• A primary amine group (–NH₂)
• An α-methyl group attached to the carbon adjacent to the amine

Functional groups

• Primary amine
• Aromatic phenyl ring

Stereochemistry

• Contains a single chiral center
• Exists as two enantiomers:
  • Dextroamphetamine (d-amphetamine) — the dextrorotatory isomer
  • Levoamphetamine (l-amphetamine) — the levorotatory isomer
• The two enantiomers have different pharmacological properties

Pharmacological chemical class

• Monoamine releasing agent
• Interacts primarily with:
  • Dopamine transporter (DAT)
  • Norepinephrine transporter (NET)
  • To a lesser extent, the serotonin transporter (SERT)

Structural significance

Amphetamine is the parent compound of a large family of substituted amphetamines. Small modifications to its structure produce related compounds such as:

• Methamphetamine
• MDMA (3,4-methylenedioxymethamphetamine)
• MDA (3,4-methylenedioxyamphetamine)

The addition of the α-methyl group distinguishes amphetamine from phenethylamine and increases its metabolic stability.

Physical characteristics

• Pure amphetamine is a colorless liquid in its freebase form
• More commonly encountered as crystalline salts, such as:
  • Amphetamine sulfate
  • Amphetamine hydrochloride
  • Amphetamine phosphate