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Irciniasulfonic acid B (1) was obtained from a marine sponge, Ircinia sp., together with a known multi-drug resistance modulator irciniasulfonic acid (2). Spectroscopic and chemical analyses revealed structure consisting of common unsaturated fatty acids, a novel unsaturated branched fatty acid, and a taurine. Final separation of irciniasulfonic acid B (1) was achieved with its methylated derivatives. Irciniasulfonic acid B (1) reversed the multi-drug resistance in the same way as irciniasulfonic acid.

The surface pressure (pi)-area (A), the surface potential (DeltaV)-A and the dipole moment (mu( perpendicular))-A isotherms were obtained for six cerebrosides of LLC-2, LLC-2-1, LLC-2-8, LLC-2-10, LLC-2-12, and LLC-2-15, which were isolated from Linckia laevigata, and two-component monolayers of two different cerebrosides (LLC-2 and LLC-2-8) with phospholipid of dipalmitoylphosphatidylcholine (DPPC) on a subphase of 0.15 M sodium chloride solution as a function of cerebroside compositions in the two-component systems by employing the Wilhelmy method, the ionizing electrode method, and the fluorescence microscopy. The new finding was that LLC-2 showed a stable and liquid expanded type film. Four of them (LLC-2-8, -10, -12, and -15) had the phase transition from the liquid-expanded (LE) to the liquid-condensed (LC) states at 298.2 K. The apparent molar quantity changes (Deltas(gamma), Deltah(gamma), and Deltau(gamma)) on their phase transition on 0.15M at 298.2 K were calculated. The miscibility of cerebroside and phospholipid in the two-component monolayers was examined by plotting the variation of the molecular area and the surface potential as a function of the cerebroside molar fraction (X(cerebroside)), using the additivity rule. From the A-X(cerebroside) and DeltaV(m)-X(phospholipid) plots, a partial molecular surface area (PMA) and an apparent partial molecular surface potential (APSP) were determined at the discrete surface pressure. The PMA and APSP with the mole fraction were extensively discussed for the miscible systems. Judging from the two-dimensional phase diagrams, these were found to be one type, a positive azeotropic type; all the cerebrosides were miscible with DPPC. Furthermore, assuming a regular surface mixture, the Joos equation for the analysis of the collapse pressure of two-component monolayers allowed calculation of the interaction parameter (xi) and the interaction energy (-Deltavarepsilon) between the cerebrosides and DPPC. The miscibility of cerebroside and phospholipid components in the monolayer state was also supported by fluorescence microscopy.

The surface pressure (pi)-area (A), the surface potential (DeltaV)-A and the dipole moment (mu( perpendicular))-A isotherms were obtained for two-component monolayers of two different cerebrosides (LMC-1 and LMC-2) with phospholipids of dipalmitoylphosphatidylcholine (DPPC) and with dipalmitoylphosphatidylethanolamine (DPPE) on a subphase of 0.5 M sodium chloride solution as a function of phospholipid compositions by employing the Langmuir method, the ionizing electrode method, and the fluorescence microscopy. Surface potentials (DeltaV) of pure components were analyzed using the three-layer model proposed by Demchak and Fort. The contributions of the hydrophilic saccharide group and the head group to the vertical component of the dipole moment (mu( perpendicular)) were estimated. The miscibility of cerebroside and phospholipid in the two-component monolayers was examined by plotting the variation of the molecular area and the surface potential as a function of the phospholipid molar fraction (X(phospholipid)), using the additivity rule. From the A-X(phospholipid) and DeltaV(m)-X(phospholipid) plots, partial molecular surface area (PMA) and apparent partial molecular surface potential (APSP) were determined at the discrete surface pressure. The PMA and APSP with the mole fraction were extensively discussed for the miscible system. Judging from the two-dimensional phase diagrams, these can be classified into two types. The first is a positive azeotropic type; the combinations of cerebrosides with DPPC are miscible with each other. The second is a completely immiscible type: the combination of cerebrosides with DPPE. Furthermore, a regular surface mixture, for which the Joos equation was used for the analysis of the collapse pressure of two-component monolayers, allowed calculation of the interaction parameter (xi) and the interaction energy (-Delta epsilon) between the cerebrosides and DPPC component. The miscibility of cerebroside and phospholipid components in the monolayer state was also supported by fluorescence microscopy.

Costunolide (CT), a sesquiterpene lactone constituent isolated from Saussurea lappa (Compositae), exerted an antiangiogenic effect. CT selectively inhibited the endothelial cell proliferation induced by vascular endothelial growth factor (VEGF). Further, CT was also found to inhibit the VEGF-induced chemotaxis of human umbilical vein endothelial cells (HUVECs) in a dose-dependent manner. From these results, we hypothesized that CT might inhibit angiogenesis by blocking the angiogenic factor signaling pathway. VEGF interacts with its cognate receptors, KDR/Flk-1 and Flt-1, and exerts its angiogenic effect. CT inhibited the autophosphorylation of KDR/Flk-1 without affecting that of Flt-1. Moreover, administration of CT reduced VEGF-induced neovascularization in a mouse corneal micropocket assay. These results suggest that CT may prove useful for the development of a novel angiogenesis inhibitor.

The detailed structure elucidation of the three new cytotoxic sesterterpenoids, inorolides A(1), B(2), and C(3), which have been isolated from a Japanese nudibranch Chromodoris inornata was described. In addition, five new scalarane-type sesterterpenoids, 4 – 8 isolated in this time, were characterized by the spectroscopic analyses.

Four new amphilectane-type diterpenoids, sinulobatins A (1), B (2), C (3) and D (4) were isolated from the Japanese soft coral Sinularia nanolobata. Their structures were determined based on spectroscopic evidence and single crystal X-ray analysis. The absolute stereochemistry of 1 was elucidated on the basis of its CD spectrum. These compounds exhibited cytotoxicity against L1210 cells and KB cells in vitro with IC50 values of 3.0 – 7.7 μg/mL.

Seven new cytotoxic spongian diterpenoids, dorisenones A ( 1 ), B ( 2 ), C ( 3 ), D ( 4 ), 7α-hydroxyspongian-16-one ( 5 ), 15α, 16α-diacetoxy-11, 12β-epoxyspongian ( 6 ) and 7α-acetoxydendrillol-3 ( 7 ) were isolated from a Japanese marine mollusk Chromodoris obsoleta (Chromodorididae), together with four known spongian diterpenoids. Their structures have been elucidated by spectroscopic evidence and single crystal X-ray analysis.

A sterol derivative, orostanal, was obtained from a marine sponge of Stelletta hiwasaensis. Spectroscopic analysis and synthetic study revealed its structure as a novel 5(6→7)abeo-sterol. Orostanal and its synthetic analog induce apoptosis in human acute promyelotic leukemia cell.

Three cytotoxic sesterterpenoids, inorolide A(1), B(2), and C(3), were isolated from a Japanese nudibranch Chromodoris inornata (Chromodorididae). Their structures have been elucidated by single crystal X-ray and spectroscopic analyses.

The flowers of Albizzia julibrissin are used as a sedative in oriental traditional medicine. The phytochemical study of this plant allowed the isolation of two flavonol glycosides, quercitrin (1) and isoquercitrin (2). The sedative activity of these compounds was evaluated, and both compounds 1 and 2 increased pentobarbital-induced sleeping time in dose-dependent manner in mice. These results support the use of the flowers of this plant as a sedative agent.

The acyl moiety of the quillajasaponins, one of the most important immunological adjuvants, was determined to be 3-(S), 5-(S)-dihydroxy-6-(S)-methyl-octanoic acid by enantioselective synthesis.

A novel bioactive acetogenin, aplyparvunin (1) was isolated from the Japanese marine mollusk Aplysia parvula (Aplysiidae). Its structure has been elucidated by spectroscopic evidence and a single crystal X-ray analysis.

From fresh Pinus contorta Doug (Coastal) needles four flavonol acylated glucosides and 6-methyl-kaempferol 3-β- D -glucoside were isolated. The three monoacylated glucosides were kaempferol-3-β- D (6- O - p - coumaryl)glucoside, isorhamnetin-3-β- D -(6- O -acetyl)glucoside, quercetin-3-β- D -( p -coumaryl)glucoside and the diacyl compound was kaempferol-3-β- D -(di- p -coumaryl)glucoside.

Three new triterpenoid saponins were isolated from the barks of Zizyphus joazeiro and characterized as jujubogenin 3- O -α- l -arabinofuranosyl-(1 → 2)-[β- d -glucopyranosyl(1 → 3)]-α- l -arabinopyranoside, its 4‴- O -sulphate and 3″,4‴-di- O -sulphate, respectively. FAB-MS was useful in providing information on the molecular weight of the complex oligoglycoside sulphates.

From the stem bark of Symplocos spicata a mixture of triterpenoid saponins was obtained. It behaved as a pure compound in TLC and HPLC, but heterogeneity was suspected on the basis of chemical and NMR spectral data. It was separated to give two analogous glycosides, which were identified as 3,28- O -bis-β- d -glucopyranosides of 19α-hydroxyarjunolic and 19α-hydroxyasiatic acids.

A hexamethylphosphoric triamide proved to be a useful solvent for negative ion fast atom bombardment mass spectrometry (FABMS) of underivatized gangliosides, using a conventional glycerol matrix. Analysis of the gangliosides using a hexamethylphosphoric triamide was more convenient and more efficient not only for molecular weight determination but also for elucidating the structure of the carbohydrate sequence. We also noted the significance of the high polarity of the solvent as well as the electron pair donicity of the matrix system for negative ion FABMS of underivatized gangliosides.

The β- d -glucopyranosides of zingerone, rheosmin acetoxydihydro- p -coumaryl alcohol, chavicol, benzoic acid and 2(or 4)-hydroxy-4(or 2)- methoxyprop-1-ene were isolated from the water soluble fraction of Pinus contorta needles, in addition to a dilignol- l -rhannopyranoside.

Three compounds, an acid and two glycosidic acids, derived from the acyl moieties of quillajasaponin were obtained from the alkaline hydrolysate of the saponin mixture. On the basis of chemical and spectral evidence, they were identified as 3,5-dihydroxy-6-methyl-octanoic acid, 3,5-dihydroxy-6-methyl-octanoic acid 5- O -α- L -arabinofuranoside and 5- O -α- L -rhamnopyranosyl-(1 → 2)-α- L -arabinofuranoside. The first compound was, in fact, isolated and characterized as its lactone form. FDMS was useful in providing information on the M , of the unique acid and glycosidic acids.

Four monolignol glucosides have been isolated and identified from the needles of Pinus contorta. Chavicol 4-O-α- L -arabinofuranosyl-(1 →

Field desorption mass spectra of underivatized saponios, naturel oligoglycosides of physiological activity, showed intense ions formed by attachment of alkali cations to the neutral molecule and to structurally highly significant subunits. This cationization was generated by small amounts of alkali salts which were present in samples after isolation from biological material. When the mass spectre were produced by laser-supported desorption and were recorded at high resolution on vapor-deposited AgBr plates unambiguous determination of the molecular weghts (in the mass range from 700 to 1400) was performed. Moreover, ions formed by direct bond cleavages in the oligosaccharide moiety of the natural saponins clearly gave information about the sequence of the sugar units in the molecule and their individual chemical structures. The formation of these fragments in FD-MS is discussed in relation to the well established mechanism of glycosidic bond cleavage by acidic solvolysis. In principle this comparison showed the usefulness of this approach for the interpretation of FD mass spectra of substances containing heteroatom linkages e.g., glycosides, esters, amides, imines, mercaptans, etc.

Two new isoprenoids, aplykurodins A and B, were isolated from the marine mollusk, Aplysia kurodai (Aplysiidae), and their structures were determined by chemical, spectral and X-ray crystallographic analyses.

Three triterpenoid sapogenins were obtained on enzymatic hydrolysis of a saponin fraction from the leaves of Pittosporum undulatum . On the basis of