Recent developments in the isolation and structure elucidation of naturally occurring iridoid compounds

Naturally occurring iridoid compounds are widely distributed in sympetalous plants and they serve as important taxonomic markers. In this survey their classification is given from the biosynthetic point of view. The recent literature concerning isolation and structure elucidation is reviewed, data on chromatography and spectroscopy, new types of iridoids and secoiridoids as well as new sugar moieties as constituents of iridoid glycosides are presented.