encountered so far in nature. A non-glycosidic iridoid, mentzetriol, has been characterized solely by spectroscopic means and a structure is proposed. The secoiridoid secoxyloganin has been found for the first time in a plant source, and the coumarin glucoside scopolin has been isolated from two species of Mentzelia . 13 C and 1 H NMR spectra of several iridoid compounds are presented. The biosynthesis