Phenylpropene

Phenylpropenes, propenylphenols, alkenylbenzenes or allylbenzenes are a class of phenylpropanoids in which a benzene ring has an allyl group attached to it. Phenylpropenes have been used as a precursors for a variety of effective insecticides.

Dosage determines concern: There is long standing and wide use as flavors at doses low enough to be insignificant, but high doses as in medicinal use can be a concern. Phenylpropene compounds are readily metabolized to reactive carcinogens which are also rapidly metabolized to safe compounds that are excreted. Thus the metabolism of these molecules quickly progresses from flavor to toxin to safe excretion.

Alkenylbenzenes at high dose can be activated metabolically (by P450, sulfotransferase) to reactive intermediates that bind DNA, but are also rapidly converted to less toxic dihydrodiol or glutathione conjugates.

The phenylpropenes, including eugenol, chavicol, safrole and estragole, are derived from the monolignols. These compounds are the primary constituents of various essential oils.

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