Cycloartane triterpenoids from Astragalus bicuspis

Three new cycloartane glycosides have been isolated from Astragalus bicuspis. They were identified as 6 alpha-hydroxy3-O-beta-xylopyranosyloxy-24,25,26,27-tetranor-9,19-cyclolanosta-16,23-lactone (1), 6 alpha-hydroxy-23-methoxy-16 beta,23(R)epoxy-24,25,26,27-tetranor-9,19-cyclolanosta-3-O-beta-xyloside (2), and 23(R),24(S),25(R),26(S)-16 beta/23,23/26,24/25-triepoxy-6 alpha,26-dihydroxy-9,19-cyciolanosta-3-O-beta-xyloside (3), on the basis of their spectroscopic data. Two known cycloartane derivatives, 4 and 5, were also obtained from this plant. Compounds 2-5 were tested for leishmanicidal activity against Leishmania major promastigotes and for cytotoxicity against 3T3 cancer cells.