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The isolation from the leaves of Gomphocarpusfruticosus (L.) R.Br. of six substances of cardenolide nature, of which uzarigenin and deglucouzarin were identified, has been reported previously [1]. In the present paper we give the results of a determination of the structures of two new glycosides, which have been called gomphotin (1, substance 3) and gomphotoxin (13, substance 5) and also of the identification of gomphoside (9), which has been isolated previously from the same plant species by Australian researchers [2].The substances isolated (1, 9, 13) gave a positive reaction for 6-deoxyhexosones with dinitrophenylhydrazine [3, 4]. On high-vacuum thermal decomposition they formed methylreductic acid (4). Their UV spectra showed a single absorption maximum in the 220 nm region (log e 4.35-4.40), which is typical for the butenolide lactone rings of cardenolides, the presence of which was confirmed by IR spectra (absorption bands at 1633 and 1750 cm-1).The positive course of the curves in the optical rotatory dispersion (ORD) spectra (Fig. 1) and absorption bands in the 1230-1240 cm -1 region showed the trans linkage of the A/B rings in the steroid nuclei and the absence of double bonds at C-5 and C-14 [6]. The acid hydrolysis of (1, 9, and 13) formed the 14-anhydroaglycons (5) and (11), the positions of the double bonds in which were conf'Lrmed by treating their acetates (7 and 12) with thionyl chloride in pyridine [5]. The ORD spectra (Fig.

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