The reinvestigation of the aerial parts of Otanthus mav~tmms afforded in addition to five known guaianohdes 33 new ones, a seco-guaianohde and three monoterpene diols The structures were elucidated by high field NMR spectroscopy and chemical transformations. The aerial parts of Pentzm albrda gave a further gualanolide closely related to one of the types from Otanthus.