Medicinal Flowers. XXVIII. Structures of Five New Glycosides, Everlastosides A, B, C, D, and E, from the Flowers of Helichrysum arenarium

Five new glycosides, everlastosides A (1), B (2), C (3), D (4), and E (5), were isolated from the methanolic extract of the flowers of Helichrysum arenarium.Their structures were elucidated on the basis of chemical and physicochemical evidence.During the course of our studies on medicinal flowers, [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] we found that the methanolic extract of the flowers of Helichrysum arenarium L. MOENCH (Asteraceae, Everlasting in English) was found to inhibit on tumor necrosis factor-α (TNF-α)-induced cytotoxicity in L929 cells. 1 Furthermore, from the methanolic extract, four flavanone and chalcone glycosides, arenariumosides I-IV, were isolated together with 46 known compounds. 1 As a continuing study on the constituents from H. arenarium, we additionally isolated five new glycosides called everlastosides A (1), B (2), C (3), D (4), and E (5).This paper deals with the isolation and structure elucidation of 1-5.