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Investigation of lipophilic exudates from the aerial parts of Balsamorhiza sagittata and B. macrophylla afforded three new highly oxygenated guaianolides (1-3), in addition to known guaianolides, germacranolide and eudesmane acids. Their chemical structures were elucidated by spectroscopic methods and the data for the compounds are reported in Tables 1 and 2 and in Experimental.

Two new norditerpenoid acids of the labdane-type (norgrindelic acids), 4,5-dehydro-6-oxo-18-norgrindelic acid (1) and 4beta-hydroxy-6-oxo-19-norgrindelic acid (2), as well as a new grindelic acid derivative, 18-hydroxy-6-oxogrindelic acid (3), were isolated from the aerial parts of Grindelia nana. In addition, the known compounds, 6-oxogrindelic acid, grindelic acid, methyl grindeloate, 7alpha,8alpha-epoxygrindelic acid, and 4alpha-carboxygrindelic acid were also isolated. The structures of the new compounds were characterized on the basis of spectroscopic analysis.

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