STUDIES ON THE CHEMICAL CONSTITUENTS OF LONICERA MACRANTHOIDES HAND.—MAZZ.

Three bisdesmosidic triterpenoid saponins Ⅰ～Ⅲ, have been isolated from the flowers of Lonicera macranthoides Hand. --Mazz. By spectral (IR, MS, ¹H-NMR and ¹³C-NMR) and chemical methods, Ⅰ was proved to be identical with the known dipsacoside B, Ⅱ and Ⅲ were new compounds named macranthoidin A and macranthoidin B. Their structures were identified as follows:The prosapogenin of Ⅱ, macranthoside A (Ⅱb), was elucidated as 3-O-β-D-glucopyranosyl-(1-3)-α-L-rhamnopyranosyl-(1--2)-α-L-arabinopyranosyl 3β, 23- dihydroxyl- olean- 12- en- 28- olic acid, Ⅱ was established as 3-O-β-D-glucopyranosyl- (1 -- 3 )-α-L-rhamnopyranosyl- (1--2)-α-L-arabinopyranosyl 3β, 23-dihydroxyl-olean- 12-en- 28-O-β-D-glucopyranosyl- ( 1 -- 6)-β- D-glucopyranoside. The prosapogenin of Ⅲ, macranthoside B(Ⅲb), was elucidated as 3-O-β-D-glucopyranosyl-(1- 4)-β-D-glucopyranosyl- ( 1 -- 3)-α-L-rhamnopyranosyl- ( 1 -- 2)-α-L-arabinopyranosyl 3β, 23-dihydroxylolean-12-en-28-olic acid, Ⅲ was established as 3-O-β-D- glucopyranosyl- ( 1 -- 4 )- β- D- glucopyranosyl- ( 1 -- 3)-α- L-rhamnopyranosyl- ( 1 -- 2 )-α- L- arabinopyranosyl 3β, 23- dihydroxyl- olean- 12- en- 28-O-β-D-glucopyranosyl-(1- 6)-β-D-glucopyranoside. Ⅱb and Ⅲb have not been reported in the literature.