Alkaloids

Pyrrolidine

e.g. Nicotine

Tropane

e.g. Atropine and cocaine

Piperidine

e.g. coniine

Pyrrolizidine

e.g. retrorsine

Quinolizidine

e.g. Lupinine

isoquinoline

e.g. codeine and morphine

Indole

e.g. Psilocybin