Heliotropin

Say ithee-lee-uh-TROH-pin

Sweet, powdery almond and cherry blossom with soft vanilla-anise warmth.

What it is: A molecule made in a lab.
When you smell it: Dry-down: hours later.
What perfumers do with it: Defines heliotrope and powdery-almond effects; softens vanillic, mimosa, carnation and ambery-fougère accords.
Worth knowing: US drug law lists it as a precursor chemical because it can be turned into MDMA.
Also called: Piperonal; 3,4-methylenedioxybenzaldehyde

Named by the house, not on the label, in 1

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