抄録
Three kinds of new, natural xanthones, named athyriol (I), isoathyriol (II), and norathyriol (IV), were isolated from the acetone extract of fresh leaves of Athyrium mesosorum MAKINO, together with mangiferin (V) and hydroquinone (III).
Norathyrial (IV) is obtained as pale yellowish brown needle crystals of m.p. above 320° and its molecular formula corresponded to C13H8O6. It was identified with 1, 3, 6, 7-tetrahydroxyanthone from its physical properties and the result of methylation.
Athyriol (I) is obtained as pale yellowish brown needle crystals of m.p. 300° (decomp.), C14H10O6. Isoathyriol forms pale yellow needle crystals of m.p. 325° (capillary), C14H10O6. Both (I) and (II) had one methoxyl group, formed a triacetate by acetylation, and 1-hydroxy-3, 6, 7-trimethoxyxanthone by methylation. Therefore, they must be monomethyl derivatives of (IV), having a methoxyl group in 3-, 6-, or 7-position. (V) was identified with mangiferin from its physical properties and formation of norathyriol by the action of hydriodic acid.
