The aerial parts of Artemisia Judaica afforded in addition to known compounds a hydroperoxide corresponding to vulgarin as well as an isomer of the latter The configurations of these lactones have been established by NOE difference spectroscopy The aerial parts of Artemisia pallida L have been investigated previously [1-3], and we have studied now material collected in Egypt In addition to taurerinolide (= vulgarin, 1) [4,5] isolated previously from this species [1,2], we obtained the isomer 3 and the hydroperoxide 2 and in addition ethyl cinnamate, α-pinene, chrysanthenone, camphor, piperitone, verbenol and the hydroperoxide 4 isolated so far only from Artemisia multica [6] The structure of 2 could be deduced from the spectral data of the product obtained by triphenyl phosphine-reduction which were identical with those of 1 The spectral data of 3 (Table 1) were close to those of 1 However, the chemical shifts of H-14 and H-15 differed characteristically NOE difference spectroscopy with both 1 and 3 clearly indicated the configuration at C-4 While 1 gave clear NOEs between H-14 and H-15 and H-6, the isomer 3 showed NOEs between H-14 and H-6 as well as between H-15 and H-5 and H-3 The configuration of 3 has been assigned previously for a lactone named barreelin [7] Comparison of the 13C NMR data, however, show that this lactone most likely is identical with vulgarin though the mp and the opti rotation differ The published 13C NMR data of 1 [8] differ only in the chemical shift of C-14 which was erroneously assigned (δ22 7 is the value of C-8 and not of C-14 which is 19 7) The 13C NMR data of 1 and 3 show some clear differences In particular, the C-15 signal is shifted downfield, most likely due to its quasi-equatorial orientation