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Imidazoline
Imidazole
t-butyl group
Tyrosine
Tetrahydroisoquinoline
Serine
Phosphate ester
Phenylethylamine
Norepinephrine
Epinephrine
Dopamine
L-Dopa
Catechol
Choline
Ethanolamine
Carbamate
Acetylcholine
Vanillylmandelic acid (VMA)
Homovanillic acid (HVA)
Tyramine
GABA
L-Glutamic acid
Benzodiazepine
Histamine
Serotonin
Phenothiazine
Piperidine
Piperazine
Urea
4,5-epoxymorphinan
Aniline