Iridoid glucosides of species of Lamium and some related genera

Species of Lamium and some related genera were investigated paper chromatographically for the presence of iridoid glucosides. Most species investigated were shown to contain such compounds. Two constituents present in several species of Lamium and in Stachys hirta could be identified with lamiol and acetyllamiol (lamioside) by comparing their properties with those reported by Scarpati and Guiso (1967) for these glucosides isolated from Lamium amplexicaule. Some of the more striking results are: 1. The difference between L. galeobdolon and the other Lamium species. L. gateobdolon has not the Lamium compounds but harpagid-type iridoid glucosides (the more common type of iridoid glucosides in Labiatae). 2. The presence of iridoid glucosides of the Lamium type in Stachys hirta. The other investigated species of Stachys have harpagid-type iridoid glucosides. 3. No traceable amounts of iridoid glucosides could be found in the allotetraploids L. mollucellifolium and L. hybridum. This is a rather strange result, because the putative parent species do accumulate iridoid glucosides.