Constituents of Umbelliferous Plants. V. On the Configuration of Archangelicin and Related Coumarins.

Abstract
The configuration of the coumarin (+)-dihydro-oroselol is related to that of ([long dash])-tubaic acid, and is shown to be 8 (S). Accordingly, the coumarins archangelicin, athamantin columbianadin, and columbia-nin also possess the configuration 8(S). The configuration of the coumarins marmesin, nodakenetin, and the chromone visamminol are determined tentatively by optical comparison. Furthermore the configuration of archangelicin and athamantin (IV) at C-9 is discussed and the 9(S) configuration is tentatively assigned to 3 coumarins.