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Constituents of Shashen (Adenophora axilliflora)
1Shanghai Institute of Pharmaceutical Industry, 1320 Beijing Xi Lu, Shanghai, China.
Abstract:
From the ethyl acetate extract of the Chinese drug "Shashen", the root of Adenophora axilliflora Borb., three triterpenoids, cycloartenol acetate ( 1), lupenone ( 2) and beta-sitosterol ( 3), two triterpenoid derivatives, beta- D-glucopyranosyl-(1-->3)-beta-sitosterol ( 7) and its 6- O-palmitoyl ester ( 6), along with two coumarins, (+)-praeruptorin A ( 4) and 3'-angeloyl-4'-isovaleryl-(3' S, 4' S) CIS-khellactone ( 5) have been isolated. A detailed (1)H-NMR analysis of compounds 6, 7 and their acetates is reported. The structure of the partial hydrolysis product of 5 is revised on the basis of spectroscopic evidences and mechanistic considerations.
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