A [1] and B [2], have been isolated from the aerial parts of Ziziphus lotus, together with the known alkaloids sanjoinenine [3], sanjoinine F [4], and frangufoline [51• Ziziphus lotus Lam. (Rhamnaceae) is a small tree that is widely distributed in the Jordan Valley. The genus Ziziphus comprises several species that are used in indigenous medicine for the treatment of various diseases (1-5). We report here the first chemical investigations of Z. lotus, yielding two new 14-membered frangulanine-type (6) cyclopeptide alkaloids from an extract of the aerial pans of Z. lotus. The new compounds, lotusanine A [1} and lotusanine B [2] were isolated along with the known alkaloids, sanjoinenine {31 (7), sanjoinine F [4] (7), and frangufoline [51 (8) (Table 1). Characterization of these compounds was achieved with the help of spectroscopic studies, especially mass spectrometry, which permitted conclusions to be drawn about the structural units (amino acids and styryl moiety) present in the compound and the manner in which they are linked (6,9). RESULTS AND DISCUSSIONCc of an alkaloidal fraction of the C6H6 extract of Z. lotus (see Experimental) gave an amorphous solid, lotusanine A [1]. The uv spectrum of 1 showed only terminal absorption. The ir spectrum exhibited bands for NH-(3260 cm '), amide carbonyls

Three new seco-ursadiene triterpenoids 1-3 together with 11 known compounds were isolated from Salvia syriaca of Jordanian origin. The compounds were identified by using NMR spectroscopy including extensive 2D NMR experiments and mass spectrometry. The structure of compound 3 was confirmed by X-ray crystallography, and the information thus obtained was used to confirm the stereochemistry of compounds 1 and 2. This is the second report of 17,22-seco-17(28),12-ursadien-22-oic acids.

Inula graveolens is a poisonous annual plant of Mediterranean origin. The invasive nature of the plant suggests that it may possess phytotoxic activity. The aim of this study was to assess the ability of I. graveolens to inhibit the growth of different plants in Petri dish and to identify the main bioactive compounds. Bio-guided fractionation of the plant extracts led to the isolation of 2,3,11β,13-tetrahydroaromaticin (THA) and ilicic acid. Both compounds showed selective and significant phytotoxic activity at 25 ppm. Root length of barley, oat, millet, tuberous canary grass and lentils were significantly reduced by 25 ppm of THA, while the root of cauliflower, cress and radish were similarly reduced by ilicic acid at 25 ppm. The structure of each compound was elucidated by using NMR and HR-MS. X-ray crystallography of THA is reported for the first time to confirm the relative stereochemistry of the compound.

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