Catalpol, a famous molecule of iridoids, possesses extensive pharmacological activities.
Our studies found that compounds with low-polarity substituents at the 6-O position of
catalpol exhibited higher NF-κB inhibitory potency than catalpol. However, catalpol derivatives
are not much focused. Here this review provides extensive coverage of naturally occurring
catalpol derivatives discovered from 1888 until 2018. It covers their distribution, chemotaxonomic
significance, chemical structures, and bioactivities from more than 200 peer-reviewed articles,
and highlights the structure-activity relationship of catalpol derivatives.