摘 要 ：Besides a series of normal C21 steroids from Marsdenia incisa incisa P. T. Li et Y．P．Li，a small amount of novel C21 steroidal glycoside(II) had been isolated. The mild acidic hydrolysis of (II) afforded genin-(I)．By spectroscopic analyses of IR,EIMS，FDMS,1H NMR，13C NMR (DEPT, PRFT),1H-1H COSY，1H－13CCOSY for(I)and(II)，(I)had been deduced as B－nor(7)-6β-formyl－pregnane-3β，5β，8β，12β，14β, 17β，20-heptatol，named neomarinogenin;(II)had been deduced as neomarinogenin 3－O- β-D－thevetopyranosyl- (1→4)- β-D- cymaropyranosyl－(1→4)-β-D－cymaropyranoside，named neomarinoside．Their physical and spectral data were as follows.
Abstract:Besides a series of normal C21 steroids from Marsdenia incisa incisa P. T. Li et Y．P．Li，a small amount of novel C21 steroidal glycoside(II) had been isolated. The mild acidic hydrolysis of (II) afforded genin-(I)．By spectroscopic analyses of IR,EIMS，FDMS,1H NMR，13C NMR (DEPT, PRFT),1H-1H COSY，1H－13CCOSY for(I)and(II)，(I)had been deduced as B－nor(7)-6β-formyl－pregnane-3β，5β，8β，12β，14β, 17β，20-heptatol，named neomarinogenin;(II)had been deduced as neomarinogenin 3－O- β-D－thevetopyranosyl- (1→4)- β-D- cymaropyranosyl－(1→4)-β-D－cymaropyranoside，named neomarinoside．Their physical and spectral data were as follows.