BIOLOGICALLY-ACTIVE CLERODANE-TYPE DITERPENE GLYCOSIDES FROM THE ROOT-STALKS OF DICRANOPTERIS-PEDATA

The molecular structure of the biologically active diterpene alcohol i solated previously from the root-stalks of Dicranopteris pedata and Gl eichenia japonica was confirmed to be (6S, 13S)-cleroda-3,14-diene-6,1 3-diol by an X-ray crystallographic analysis, together with applicatio n of the octant rule to the Cotton effect observed in the CD spectrum of its 6-keto derivative. Further investigation of the root-stalks of D. pedata has resulted in the isolated two new glycosides, which were characterised as (6S,13S)-6-O-[beta-D-glucopyranosyl- (1-->4)-alpha-L- rhamnopyranosyl]-13-O-[alpha-L- anosyl-(1-->4)-beta-D-fucopyranosyl]-c leroda-3,14- diene and -O-[beta-glucopyranosyl]-13-O-[beta-fucopyranos yl- (1-->2)-alpha-rhamnopyranosyl]-cleroda-3,14-diene. Of these two gl ycosides, the former glycoside accelerated the growth of the stems of lettuce and inhibited the growth of the roots. (C) 1997 Elsevier Scien ce Ltd.