STRATEGY FOR THE ISOLATION AND IDENTIFICATION OF COUMARINS WITH CALCIUM ANTAGONISTIC PROPERTIES FROM THE ROOTS OF ANGELICA-ARCHANGELICA

Fifteen coumarins, 2'-angeloyl-3'-isovaleryl vaginate (4), archangelicin (3), oxypeucedanin hydrate (8), bergapten (5), byakangelicin angelate (15), imperatorin (11), isoimperatorin (6), isopimpinellin (13), 8-[2-(3-methylbutroxy)-3-hydroxy-3-methylbutoxy]psoralen (12), osthol (1), ostruthol (9), oxypeucedanin (7), phellopterin (14), psoralen (2) and xanthotoxin (10), have been isolated from a chloroform extract of the roots of Angelica archangelica L. subsp. archangelica (Apiaceae). 2, 4, 12, and 15 are reported for the first time from A. archangelica L. The isolation was carried out using medium pressure liquid chromatography (MPLC) using the normal phase mode and then subsequently using a combination of the reversed and normal phase techniques. The eluents were optimized by thin layer chromatography and high performance liquid chromatography preassays according to the "PRISMA" system, and then transferred without modification of the solvent selectivity to preparative MPLC separations. The structures of the compounds were elucidated by a combination of spectroscopic methods. The isolation was carried out from a chloroform extract which in earlier tests had exhibited calcium blocking activity on the uptake of Ca-45(2+) in clonal rat pituitary GH4C1 cells. The calcium antagonistic activity of the isolated compounds was then tested using the same method as for the extracts. All the coumarins tested exhibited calcium antagonistic activity. Archangelicin showed activity significantly higher than that of verapamil in this test system.