Isobutyl methoxypyrazine

Say iteye-soh-BYOO-til meth-ok-see-PYE-ruh-zeen

Raw green bell pepper, earthy pea pod and crushed leaves.

What it is: A molecule made in a lab.
Where it comes from: synthesized, natural in bell peppers and some grapes
When you smell it: Top notes: the first minutes.
What perfumers do with it: Used at parts per million to add a raw, realistic vegetable-green bite to galbanum and green accords.
Worth knowing: People smell it at about two parts per trillion in water; it's the green-pepper note in Sauvignon blanc.
Also called: 2-Isobutyl-3-methoxypyrazine; IBMP; bell pepper pyrazine

Not on the label of any of the 232 perfumes read so far.

Sources