APPLICATION OF NEW TECHNIQUES OF NMR IN THE STRUCTURE ELUCIDATION OF TWO NEW SAPONINS．ASPEROSAPONIN F AND Hl，AND SPECTRAL RULES INVOLVED

Two new triterpenoid saponins，i.e．asperosaponin F(6 sugars)and H₁(8 sugars)，were isolated from the ethanolic extract of the root of Dipsacus asperoedes C．Y．Cheng et T． M．Ai．Their structures were identified by chemical and spectral methods，e．g．¹HNMR，¹³CNMR，2D ¹H-¹H COSY，selective long range DEPT，NOEDS，1D multiple relay COSY．The structures were elucidated as，3-O-β-D-xylopyranosyl(1→4)-β-D-glucopyranoyl(1→4) α-L-rhamnopyranosyl(1→3)-β-D-galactopyranosyl(1→3)-α-L-rhamnopyranosyl(1→2)-α-L-arabinopyranosyl-hederagenin(asperosaponin F，I)and 28-O-β-D-glucopyranosyl(1→6)-β-D-glucopyranoside of F(asperosaponin H₁，II)．The spectral features for elucidating the structure of saponins containing more than four sugars are also described．