| Abstract
| - Three new cycloartane-type triterpene glycosides, brachyosides A (1), B (3), and C (2), from the roots ofAstragalus brachypterus and one new glycoside, cyclocephaloside II (4), from the roots of Astragalusmicrocephalus have been isolated together with five known saponins, astragalosides I, II, and IV,cyclocanthoside E, and cycloastragenol. The structures of the new compounds were established as 3-O-[β-d-xylopyranosyl(1→3)-β-d-xylopyranosyl-6-O-β-d-glucopyranosyl-3β,6α,16β,24(S),25-pentahydroxycycloartane (1), 3-O-β-d-xylopyranosyl-6-O-β-d-glucopyranosyl-24-O-β-d-glucopyranosyl-3β,6α,16β,24(S),25-pentahydroxycycloartane (2), 20(R),24(S)-epoxy-6-O-β-d-glucopyranosyl-3β,6α,16β,25-tetrahydroxycycloartane(3), and 20(R),24(S)-epoxy-3-O-(4‘-O-acetyl)-β-d-xylopyranosyl-6-O-β-d-glucopyranosyl-3β,6α,16β,25-tetrahydroxycycloartane (4). For the structure elucidations, 1D- and 2D-NMR experiments and FABMSwere used.
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