Aminoindanes

The amphetamine side chain welded into an indane ring, so the amine and the α-methyl are locked in one conformation instead of rotating freely. That rigidity changes what the transporters do with them: MDAI and MMAI release serotonin with comparatively little dopamine release, 2-aminoindane is closer to a plain stimulant, and 5-IAI sits between. One family, several quite different drugs.

They are filed under Stimulants by scaffold and by their catecholamine members, even though the serotonin-releasing ones are marketed as substitutes for entactogens — being sold as a replacement for something is not evidence of behaving like it. Serotonin release is also what makes combination with MAOIs and serotonergic antidepressants a serotonin syndrome risk. Human data is thin for every member of this family, and thinnest exactly where the marketing is most confident.