The isolation and identification of a new pregnene-glycoside from Pseudoplexaura wagenaari using two-dimensional NMR methods

Extracts from four gorgonians of the genera PseudoDlexaura, P. porosa, P. flagellosa. P. crucis, and P. wagenaari have been shown to contain several novel sterols and diterpenes. The present contribution includes the isolation and identification of a new pregnene-type steroidal-glycoside from P. wagenaari. Using several two-dimensional (2D) NMR (COSY, heteronuclear chemical shift correlation (CSCM) and heteronuclear relayed coherence transfer (RCT2D) techniques in combination with classical spectroscopic and chemical techniques, I was able to establish the structure as 3p-(D-galactose)-pregna-5,2O-dien (32).