This article is from the Chemistry FAQ, by Bruce Hamilton B.Hamilton@irl.cri.nz with numerous contributions by others.
Many low molecular weight sulfur-containing compounds tend to induce adverse
reactions in people, even if they have not encountered them before, eg the
glandular emissions of skunk (n-butyl mercaptan, dicrotyl sulfide).
Butyric acid reminds people of vomit, and cadaverine ( 1,5 Pentadiamine )
reminds people of rotten tissue, but without an earlier association, they
may not regard them as unusually obnoxious.
 
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