Iridoid

Iridoids are a type of

The chemical structure is exemplified by iridomyrmecin, a defensive chemical produced by the ant genus Iridomyrmex, for which iridoids are named. Structurally, they are bicyclic cis-fused cyclopentane-pyrans. Cleavage of a bond in the cyclopentane ring gives rise to a subclass known as secoiridoids, such as oleuropein and amarogentin.

Occurrence

Aucubin and catalpol are two of the most common iridoids in the plant kingdom.

The iridoids produced by plants act primarily as a defense against herbivores or against infection by microorganisms.^{[citation needed]} The variable checkerspot butterfly also contains iridoids obtained through its diet which act as a defense against avian predators.^[2] To humans and other mammals, iridoids are often characterized by a deterrent bitter taste.

Aucubin and catalpol are two of the most common iridoids in the plant kingdom.^{[citation needed]} Iridoids are prevalent in the plant subclass Asteridae, such as Ericaceae, Loganiaceae, Gentianaceae, Rubiaceae, Verbenaceae, Lamiaceae, Oleaceae, Plantaginaceae, Scrophulariaceae, Valerianaceae, and Menyanthaceae.^[3]

Iridoids have been the subject of research into their potential biological activities.^[3][4]

Biosynthesis

The iridoid ring scaffold is synthesized, in plants, by the enzyme

• medicinal plants, such as Morinda citrifolia