Isodaucanes and Daucanes

Bonds from C-1 to C-7 and from C-1 to C-10 in famesane formally build up the sesquiterpene skeleton of isodaucanes which are converted to daucanes by migration of one methyl group (C-14) from C-7 to C-8. 

Isodaucanes such as (+)-6,10-epoxy-7(14)-isodaucene and 7(14)-isodaucen-10-one are constituents of the oil of sage from Salvia sclarea (Labiatae). The name dau-cane stems from the carrot Daucus carota (Umbelliferae), from which (+)-4,8-daucadiene, (+)-8-daucen-5-ol and (-)-5,8-epoxy-9-daucanol have been isolated. 

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