Identification of psoralen, 8-methoxypsoralen, isopimpinellin, and 5,7-dimethoxycoumarin in Pelea anisata H. Mann.

5,7-dimethoxycoumarin and isopimpinellin, together with the well-known phototoxic, photo-irritant furanocoumarins psoralen and 8-methoxypsoralen, were isolated and identified from leaves and fruits of Pelea anisata H. Mann, a plant whose fruit are used in the construction of mohikana leis used in parts of the Hawaiian Islands. The presence of phototoxic furanocoumarins would explain the occurrence of photodermatitis in the wearers of the leis.