[civilitty]

Knee-jerk reactions like that aren't helpful with biological compounds. In this case they're both benzophenanchridine/isoquinoline alkaloids with the same functional groups: a methylenedioxy bridge and at least one methoxy group.

L- and D-methamphetamine are a rather unique case because their enantiomeric forms have different effects on the central and peripheral nervous systems. They're much more different from each other structurally than berberine is from sanguinarine.