Oxane

Say itOK-sayn

Tropical passion fruit and grapefruit, green and sulfurous-catty.

What it is: A molecule made in a lab.
Where it comes from: nature-identical, found in yellow passion fruit
When you smell it: Top notes: when you spray it.
What perfumers do with it: At traces, gives exotic juiciness to passion fruit, mango, grapefruit and cassis accords.
Worth knowing: Yellow passion fruit contains it naturally, and noses detect it at around three parts per billion.
Also called: 2-Methyl-4-propyl-1,3-oxathiane; Tropathiane (Givaudan)

Not on the label of any of the 1080 perfumes read so far.

Sources