IRIDOID GLYCOSIDES FROM LINARIA SPECIES

The iridoid composition of four Linaria species has been investigated. Two new iridoids along with known compounds were isolated and identif ied. The new iridoid glucoside, 7,8-epi-antirrinoside, found in L. dal matica, is the first iridoid glucoside with an alpha-orientation of th e 7,8-epoxide ring, while 6beta-hydroxyantirride, found in L. genistif olia and L. peloponnesiaca, appears as a second representative of the rare antirride iridoid type. Antirride was found for the first time in L. simplex. Structure elucidations were carried out mainly by spectra l methods and molecular mechanics calculations. Chemosystematic relati onships arc also discussed.