Germacranolides, guaianolides and eudesmanolides from Greenmaniella resinosa

The aerial parts of Greenmaniella resinosa afforded, in addition to known compounds, 22 new ones: nine germacranolides, seven eudesmanolides, five guaianolides and a bisabolene derivative. The structures were elucidated by spectroscopic methods and by some chemical transformations including partial synthesis. The chemotaxonomic situation of Greemnaniella and the biogenetic relationships of the compounds are discussed briefly.