Purpurenol, a Highly Oxygenated Coumarin From Pterocaulon-purpurascens

A new 5,6,7,8-tetraoxygenated coumarin, named purpurenol, was isolated from aerial parts of Pterocaulon purpurascens. Its structure was elucidated on the basis of the spectral data and was confirmed by X-ray analysis

5-(3-methy-2-butenyloxy)-6,7-methylenedioxy-coumarin, a 5,6,7-trioxygenated Coumarin From Pterocaulon Virgatum

The coumarin 1 [5-(3-methyl-2-butenyloxy)-6,7-methylenedioxycoumarin] and the recently reported 5-methoxy-6,7-methylenedioxycoumarin, have been isolated from a petroleum ether extract of Pterocaulon virgatum. The structure of 1 was determined on the basis of X-ray crystallographic analysis and spectroscopic data

REVISION OF THE STRUCTURE OF OBTUSIFOL.

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