[Studies on the structures of two new alkaloidal glucosides of Nauclea officinalis Pierre ex pitard]

Three indolic alkaloidal glucosides were isolated from the polar fraction of the stems of Nauclea officinalis. Two are new, named naucleoside (Ia) and nauclecosidine (IIa) and the other is a well known alkaloid, vincoside lactam. The structures of Ia and IIa were elucidated on the basis of spectroscopic data (IR, MS, HNMR and CNMR) and chemical evidence.