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Ten new glycosides, named dracunculifosides A-J, were isolated along with sixteen known glycosides from the aerial part of Baccharis dracunculifolia DC. (Compositae). The structures of these glycosides were determined on the basis of spectral and chemical evidence. These new glycosides consisted of beta-D-glucopyranose or beta-D-apiofuranosyl-(1-->6)-beta-D-glucopyranose, and most possess an (E)-caffeoyl group.

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Highly sensitive successive determinations for PtII and SeIV ions have been developed based upon reactions with 1,4-dibromo-2,3-diaminonaphthalene (Br2DAN), which forms a near-infrared (NIR) absorbing complex (epsilon = 1.2 x 10(5) l mol-1 cm-1 at 800 nm) and an emissive complex (ex. 386 nm, em. 604 nm) for PtII and SeIV ions, respectively, in acidic aqueous micellar solutions. In the presence of a cationic surfactant, cetyltrimethylammonium chloride, the detection limits for PtII and SeIV ions are 1.2 ng ml-1 (3 sigma) and 0.98 ng ml-1 (S/N = 3), respectively. Hydrobromic acid plays a key role to enhance the color development of the NIR-absorbing PtII complex. The influences of CuII and ZnII ions at the normal human serum levels are readily tolerated, and interference from FeIII ion at 35 mumol l-1 is circumvented by the addition of 50 mumol l-1 of polyaminocarboxylates, such as EDTA.

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Thirty three compounds were obtained from the bulbs of Urginea maritima (Liliaceae). The compounds were identified by means of fast atom bombardment mass spectrometry (FAB-MS), nuclear magnetic resonance (1H-NMR), (13C-NMR), nuclear overhauser effects (NOE) and two dimensional (2D) NMR. Ten of them were new natural compounds. Nine were bufadienolides and only one was lignan in these compounds.

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Twenty-nine new oxypregnane glycosides were obtained along with two known cardenolides, frugoside and gofruside, and three known 12-O-acylated pregnane glycosides from the roots of Asclepias incarnata L. (Asclepiadaceae). By detailed studies of the 1H- and 13C-NMR spectra, the structures were determined to be tri- to penta glycosides of isolineolon, 12-O-acetyllineolon, ikemagenin, 12-O-benzoylisolineolon, and two new 12-O-acylated pregnanes.

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Thirty new steroidal glycosides were obtained from the aerial part of Asclepias incarnata L. (Asclepiadaceae). These glycosides were confirmed to have lineolon, isolineolon, 12-O-acetyllineolon, 12-O-(Z)-cinnamoyllineolon, metaplexigenin, 15 beta-hydroxylineolon, 15 beta-hydroxyisolineolon, 16 alpha-hydroxyisolineolon, 12-O-tigloyl-16 alpha-hydroxyisolineolon as the aglycone and 2,6-dideoxyhexopyranose as the sugar sequence by spectroscopic methods and chemical evidence.

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The aerial part of Asclepias incarnata afforded 34 pregnane glycosides. These were confirmed to have lineolon, isolineolon, ikemagenin, 12-O-nicotinoyllineolon, deacylmetaplexigenin, metaplexigenin, rostratamine, 12-O-acetyllineolon, 15beta-hydroxylineolon and 15beta-hydroxyisolineolon moieties as their aglycones, and 2.6-dideoxyhexopyranose, glucopyranose and allopyranose as the corresponding sugar constituents. Their structures were determined using both spectroscopic and chemical methods.

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The roots of Cynanchum caudatum M. (Asclepiadaceae) afforded eleven new pregnane glycosides which had cynanchogenin, caudatin, 12-O-benzoyllineolon and 12-O-benzoyldeacylmetaplexigenin as the aglycone moiety and 2,6-dideoxy-3-O-methylhexopyranoses as component sugars. The structures of these compounds were elucidated by spectroscopic methods and from chemical evidence.

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The aerial part of Cynanchum caudatum afforded 10 new pregnane glycosides which had sarcostin or deacylmetaplexigenin as the aglycone moiety. The structures of these compounds were elucidated by spectroscopic methods and from chemical evidence.

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Asclepias fruticosa afforded, in addition to five known pregnane glycosides and 11 known cardenolide glycosides, four new pregnane glycosides and eleven new cardenolide glycosides. Structures of these compounds were elucidated by spectroscopic methods and from chemical evidence.

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Five novel steroidal glycosides 2-6 were isolated from the whole plant of Asclepias fruticosa L. (Asclepiadaceae). The structures of these steroidal glycosides were determined on the basis of spectral and chemical evidence. All of these glycosides contain 2,6-dideoxyhexopyranoses as component sugars and their structures were elucidated as polyoxypregnane-type glycosides, which have lineolon as the aglycone moiety.

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Verbascum thapsus afforded, in addition to three known phenylethanoid glycosides and four lignan ones, five new phenylethanoid glycosides and one new lignan glycoside. Structures of the compounds were elucidated by spectroscopic methods and chemical evidence.

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