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Metastasis occurs when cancer cells detach from a tumor, travel to distant sites in the body and develop into tumors in these new locations. Most cancer patients die from metastases. Among the various forms of cancer metastasis, lymphatic metastasis is an important determinant in cancer treatment and staging. In this study, we investigated lymphangiogenesis inhibitors from crude drugs used in Japan and Korea. The three crude drugs Saussureae Radix, Psoraleae Semen and Aurantti Fructus Immaturus significantly inhibited the proliferation of temperature-sensitive rat lymphatic endothelial (TR-LE) cells in vitro. By a chromatographic method using bioassay-guided fractionation methods, costunolide (1) and dehydrocostus lactone (2) from S. Radix, p-hydroxybenzaldehyde (3), psoralen (4), angelicin (5), psoracorylifol D (6), isobavachalone (7), bavachinin (8) Δ(3),2-hydroxybakuchiol (9) and bakuchiol (10) from P. Semen and cis-octadecyl ferulate (11), (2R)-3β,7,4'-trihydroxy-5-methoxy-8-(γ,γ-dimethylallyl)-flavanone (12), (2S)-7,4'-dihydroxy-5-methoxy-8-(γ,γ-dimethylallyl)-flavanone (13) and umbelliferone (14) from A. F. Immaturus were obtained. Three compounds (compounds 11-13) from A. F. Immaturus were isolated for the first time from this medicinal plant. Among isolated compounds, ten compounds (compounds 1, 2, 6-12, 13) showed an inhibitory effect on the proliferation and the capillary-like tube formation of TR-LE cells. In addition, all compounds except compound 12 showed selective inhibition of the proliferation of TR-LE cells compared to Hela and Lewis lung carcinoma (LLC) cells. These compounds might offer clinical benefits as lymphangiogenesis inhibitors and may be good candidates for novel anti-cancer and anti-metastatic agents.

Three new ganglioside molecular species, termed PNG-1, PNG-2A, and PNG-2B were isolated from pyloric caeca of the starfish Protoreaster nodosus. Their structures were elucidated using a combination of spectroscopic and chemical methods, and characterized as 1-O-[8-O-methyl-N-acetyl-α-neuraminosyl-(2→3)-β-galactopyranosyl]-ceramide for PNG-1, 1-O-[β-galactofuranosyl-(1→3)-α-galactopyranosyl-(1→4)-8-O-methyl-N-acetyl-α-neuraminosyl-(2→3)-β-galactopyranosyl]-ceramide for PNG-2A, and 1-O-[β-galacto furanosyl-(1→3)-α-galactopyranosyl-(1→9)-N-acetyl-α-neuraminosyl-(2→3)-β-galactopyr anosyl]-ceramide for PNG-2B. PNG-2A and PNG-2B represent the first GM4 elongation products in nature.

Two manzamine-class alkaloids, manzamine A (1) and 8-hydroxymanzamine (2) were isolated from a Japanese marine sponge Acanthostrongylophora aff. ingens, together with three known alkaloids manzamine E (3), manzamine F (4), and manzamine X (5). The spectral features of 1 and 2 were different from the reported data. Detailed structure analysis using 2D NMR revealed the structure of 1 and 2 as a free base form of hydrochloric salt. These manzamine-class alkaloids showed neuritogenic activity against Neuro 2a cells.

This review will summarize the authors’ studies on the structure and the biological activities of the gangliosides from echinoderms. Over 40 gangliosides have been obtained and characterized from 13 kinds of echinoderms, namely, Acanthaster planci, Asterina pectinifera, Asterias amurensis versicolor, Astropecten latespinosus, Luidia maculata, Linckia laevigata (starfish), Cucumaria echinata, Holothuria pervicax, H. leucospilota, Stichopus japonicus, S. chloronotus (sea cucumber), Comanthus japonica (feather star) and Ophiocoma scolopendrina (brittle star). The structural feature of the echinoderms gangliosides was their unique carbohydrate moieties. The biological property of the gangliosides from echinoderms, taking up in this review, was mainly neuritogenic activity.

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.

Four new steroid di-O-sulfates, latespinoside A (1), B (2), C (3), and D (4), were isolated from the crude glycoside fraction of the chloroform/methanol extract of the starfish Asteropecten latespinosus as minor components. Their structures were determined on the basis of spectral data as disodium salts of (20S)-20-hydroxy-6α-(4-O-sulfo-β-D-quinovopyranosyloxy)-3β-sulfooxy-5α-cholesta-9(11),24-diene (1), (20S)-20-hydroxy-6α-(4-O-sulfo-β-D-quinovopyranosyloxy)-3β-sulfooxy-5α-cholest-9(11)-ene (2), 6α-(4-O-sulfo-β-D-quinovopyranosyloxy)-3β-sulfooxy-5α-cholesta-9(11),17(20)Z,24-trien-23-one (3), and 6α-(4-O-sulfo-β-D-quinovopyranosyloxy)-3β-sulfooxy-5α-androst-9(11)-en-17-one (4). Compound 4 is, to the authors' knowledge, the first androstane derivative isolated from starfish. In addition, compounds 3 and 4 show weakly cytotoxic activity against murine lymphoma L1210 cells in vitro.

Three new disialo- and trisialo-gangliosides, CEG-6 (6), CEG-8 (8), and CEG-9 (9), were obtained, together with one known ganglioside, HLG-3 (7), from the lipid fraction of the chloroform/methanol extract of the sea cucumber Cucumaria echinata. The structures of the new gangliosides were determined on the basis of chemical and spectroscopic evidence to be 1-O-[alpha-L-fucopyranosyl-(1--11)-(N-glycolyl-alpha-D-neuraminosyl)-(2--4)-(N-acetyl-alpha-D-neuraminosyl)-(2--6)-beta-D-glucopyranosyl]-ceramide (6) and 1-O-[(N-glycolyl-D-neuraminosyl)-(2--11)-(N-glycolyl-D-neuraminosyl)-(2--4)-(N-acetyl-D-neuraminosyl)-(2--6)-D-glucopyranosyl]-ceramide (8, 9). The ceramide moieties of each compound were composed of an homogeneous sphingosine or phytosphingosine base and heterogeneous 2-hydroxy or nonhydroxylated fatty acid units. These gangliosides showed neuritogenic activity toward the rat pheochromocytoma cell line PC-12 in the presence of nerve growth factor.

Three new monosialo-gangliosides, CEG-3 (3), CEG-4 (4), and CEG-5 (5), were obtained, together with two known gangliosides, SJG-1 (1) and CG-1 (2), from the lipid fraction of the chloroform/methanol extract of the sea cucumber Cucumaria echinata. The structures of the new gangliosides were determined on the basis of chemical and spectroscopic evidence to be 1-O-[4-O-acetyl-alpha-L-fucopyranosyl-(1--11)-(N-glycolyl-alpha-D-neuraminosyl)-(2--6)-beta-D-glucopyranosyl]-ceramide (3) and 1-O-[alpha-L-fucopyranosyl-(1--11)-(N-glycolyl-alpha-D-neuraminosyl)-(2--6)-beta-D-glucopyranosyl]-ceramide (4, 5). The ceramide moieties of each compound were composed of heterogeneous sphingosine or phytosphingosine bases, and 2-hydroxy or nonhydroxylated fatty acid units. These gangliosides showed neuritogenic activity toward the rat pheochromocytoma cell line PC-12 in the presence of nerve growth factor.

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.

Six new ceramide dihexosides, amphimelibiosides A-F (1-6), were isolated from a Japanese marine sponge Amphimedon sp. The structure of amphimelibioside C (3), which is a major component of amphimelibiosides, was determined by 2D NMR techniques, chemical degradation, and a semisynthetic method to be 1-O-[beta-D-glucopyranosyl-(1--6)-alpha-D-galactopyranosyl]-(2S,3S,4R,6E)-2-[(2'R)-2-hydroxydocosanoyl]-2-amino-6-octadecene-1,3,4-triol. The structures of the other constituents were elucidated by a combination of mass spectra, (1)H NMR, and GC-MS analysis.

A ganglioside molecular species, LLG-5 (1), has been obtained from the water soluble lipid fraction of the CHCl3/MeOH extract of the starfish Linckia laevigata. On the basis of chemical and spectroscopic findings, the structure of 1 has been elucidated. Negative ion FAB-MS provided important information both on the structure of the sugar moiety and on the molecular mass of the ganglioside. 1 is a new ganglioside molecular species possessing a 2-->11 linked linear-type trisialosyl moiety. Moreover, 1 exhibited neuritogenic activity in rat pheochromocytoma PC-12 cells in the presence of nerve growth factor.

A new ganglioside molecular species SJG-2 has been obtained from the n-hexane-soluble lipid fraction of the chloroform/methanol extract of the sea cucumber Stichopus japonicus. On the basis of chemical and spectroscopic evidence, the structure of SJG-2 has been determined, as NeuAcα2⇄4(NeuAcα2⇄3)Galβ1⇄8NeuAcα2⇄3GalNAcβ1⇄3Galβ1⇄4Glcβ1⇄1Cer. The new ganglioside SJG-2, possessing a unique carbohydrate moiety, is the first ganglioside containing either a branched sugar chain moiety or an N-acetylgalactosamine residue to be isolated from a sea cucumber. Partial hydrolysis with hot water and dilute acetic acid has proved useful for the structure elucidation of the complex oligosaccharide moieties. Moreover, the ganglioside SJG-2 exhibits neuritogenic activity toward the rat pheochromocytoma cell line PC12 cells in the presence of NGF. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003)

The fragmentation of the sodium adduct ions for tert-butoxycarbonyl-L-prolyl-L-proline ethyl ester (Boc-L-Pro-L-Pro-OEt) was compared with that for Boc-D-Pro-L-Pro-OEt in positive-ion electrospray ionization (ESI) mass spectrometry. In the collision-induced dissociation (CID) mass spectra of the [M + Na](+) ions, the abundance of the [M + Na - C(CH(3))(3) + H](+) ion, which is due to the loss of a tert-butyl group from the [M + Na](+) ion for Boc-D-Pro-L-Pro-OEt, was about eight times higher than that for Boc-L-Pro-L-Pro-OEt. In addition, in the CID spectra of the sodium adduct fragment ion ([M + Na - Boc + H](+)), the abundance of the [M + Na - Boc - prolylresidue + H](+) ion, which is due to the loss of prolyl residue from the [M + Na - Boc + H](+) ion for Boc-L-Pro-L-Pro-OEt, was about five times higher than that for Boc-D-Pro-L-Pro-OEt. These results indicate that Boc-L-Pro-L-Pro-OEt was distinguished from Boc-D-Pro-L-Pro-OEt by the CID mass spectra of the sodium adduct ions in ESI mass spectrometry. The optimized geometries of the [M + Na](+) and the [M + Na - Boc + H](+) ions calculated by ab initio molecular orbital calculations suggest that the chiral recognition of these diastereomers was due to the difference of the orientation of a sodium ion to the oxygen and nitrogen atoms in dipeptide derivatives, and to the difference of the total energies between them.

Three ganglioside molecular species, SCG-1, SCG-2, and SCG-3, were obtained from the lipid fraction of the chloroform-methanol extract of the sea cucumber Stichopus chloronotus. On the basis of chemical and spectroscopic evidence, the structures of these gangliosides have been determined to be 1-O-[(N-glycolyl-alpha-D-neuraminosyl)-(2-->6)-beta-D-glucopyranosyl]-ceramide (SCG-1), 1-O-[8-O-sulfo(major)-(N-acetyl-alpha-D-neuraminosyl)-(2-->6)-beta-D-glucopyranosyl]-ceramide (SCG-2), and 1-O-[alpha-L-fucopyranosyl-(1-->11)-(N-glycolyl-alpha-D-neuraminosyl)-(2-->6)-beta-D-glucopyranosyl]-ceramide (SCG-3). The ceramide moieties were composed of heterogeneous long-chain base and fatty acid units. SCG-3 is the first type of ganglioside containing a fucopyranose in the sialosyl trisaccharide moiety. Moreover, these three gangliosides exhibited neuritogenic activity toward the rat pheochromocytoma PC12 cells in the presence of nerve growth factor.

cis-Hinokiresinol (CHR) is a norlignan constituent from Anemarrhena asphodeloides BUNGE (Liliaceae), which shows hyaluronidase inhibitory activity. In the present studies, we have demonstrated that CHR selectively inhibited endothelial cell proliferation compared with cancer cells, and especially basic fibroblast growth factor (bFGF) or vascular endothelial growth factor (VEGF)-induced endothelial cell proliferation. Furthermore, endothelial cell migration and tube formation, two important steps in the angiogenic process, were also inhibited by CHR. Moreover, CHR reduced the vessel growth induced by VEGF in the mouse corneal neovascularization model. These results suggest that CHR may prove useful for the development of a novel angiogenesis inhibitor.

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.

Two monomethylated GM(3)-Type ganglioside molecular species, 1 and 2, have been obtained from the polar lipid fraction of the chloroform/methanol extract of the starfish Luidia maculata. The structures of these gangliosides have been determined on the basis of chemical and spectroscopic evidence as 1-O-[8-O-methyl-(N-acetyl-alpha-D-neuraminosyl)-(2-->3)-beta-D-galactopyranosyl-(1-->4)-beta-D-glucopyranosyl]-ceramide (1) and 1-O-[8-O-methyl-(N-glycolyl-alpha-D-neuraminosyl)-(2-->3)-beta-D-galactopyranosyl-(1-->4)-beta-D-glucopyranosyl]-ceramide (2). The ceramide moieties were composed of heterogeneous unsubstituted fatty acid, 2-hydroxy fatty acid, sphingosine and phytosphingosine units. Compound 1, designated as LMG-3, represents new ganglioside molecular species. Compound 2 was a known ganglioside molecular species.

Three ganglioside molecular species, HLG-1 (1), HLG-2 (2), and HLG-3 (3) have been obtained from the lipid fraction of the chloroform/methanol extract of the sea cucumber Holothuria leucospilota. The structures of these gangliosides have been determined, on the basis of chemical and spectroscopic evidence, as 1-O-[(N-glycolyl-alpha-D-neuraminosyl)-(2--6)-beta-D-glucopyranosyl]-ceramide (1), 1-O-[(N-glycolyl-alpha-D-neuraminosyl)-(2--4)-(N-acetyl-alpha-D-neuraminosyl)-(2--6)-beta-D-glucopyranosyl]-ceramide (2) and 1-O-[alpha-L-fucopyranosyl-(1--11)-(N-glycolyl-alpha-D-neuraminosyl)-neuraminosyl)-(2--4)-(N-aetyl-alpha-D-neuraminosyl)-(2--6)-beta-D-glucopyranosyl]-ceramide (3). The ceramide moieties were composed of heterogeneous phytosphingosine, sphingosine and 2-hydroxy fatty acid units. Compounds 2 and 3 represent new ganglioside molecular species. These three ganglioside molecular species showed neuritogenic activity toward the rat pheochromocytoma cell line, PC-12 cell, in the presence of NGF (nerve growth factor).

Three ganglioside molecular species, OSG-0 (1), OSG-1 (2), and OSG-2 (3) have been obtained from the polar lipid fraction of the chloroform/methanol extract of the brittle star Ophiocoma scolopendrina. The structures of these gangliosides have been determined on the basis of chemical and spectroscopic evidence as 1-O-[(N-glycolyl-alpha-D-neuraminosyl)-(2--6)-beta-D-glucopyranosyl]-ceramide (1), 1-O-[8-O-sulfo-(N-acetyl-alpha-D-neuraminosyl)-(2--6)-beta-D-glucopyranosyll-ceramide (2) and 1-O-[(N-glycolyl-alpha-D-neuraminosyl)-(2--8)-(N-acetyl- and N-glycolyl-alpha-D-neuraminosyl)-(2--6)-beta-D-glucopyranosyl]-ceramide (3). The ceramide moieties were composed of heterogeneous unsubstituted fatty acid, 2-hydroxy fatty acid and phytosphingosine units. Compounds 2 and 3 represent new ganglioside molecular species.

Two novel type gangliosides CJP2 and CJP3 have been obtained from the feather star Comanthus japonica. On the basis of methylation linkage analysis combined with ammonolysis and other chemical and spectroscopic evidence, the chemical structures of CJP2 and CJP3 were determined to be alpha-9-O-Me-NeuGc-(2--3)-inositolphosphoceramide and alpha-9-O-Me-NeuGc-(2--11)-alpha-9-O-Me-NeuGc-(2--3)-inositolphosphoceramide, respectively. These gangliosides are unique in that they are inositolphosphoceramide derivatives possessing sialic acid; such gangliosides have not previously been identified. The presence of 9-O-methyl-N-glycolyl-neuraminosyl residues is also unique in naturally occurring gangliosides.

A new ganglioside molecular species named AG-1 has obtained from the whole body of starfish Acanthaster planci (crown of thorns). The structure of this ganglioside have been elucidated by enzymatic hydrolysis with the endo-type glycosidase. Enzymatic hydrolysis gave an oligosaccharide and ceramides, quantitatively. The oligosaccharide moiety was determined mainly using 2D-NMR experiments as β-Fucf-(14)-α-Galp-(14)-α-NeuAc-(23)-β-Galp-(14)-Glcp. Meanwhile, the ceramide moiety was elucidated by NMR and GC-MS analysis as the mixture of (2S,2′S,3S,4R)-2-(2′-hydroxydocosanoyl)amino-1,3,4-trihydoxyhexadecane, and (2S,2′S,3S,4R)-2-(2′-hydroxytetracosanoyl)amino-1,3,4-trihydoxyhexadecane. Reversed-phase HPLC of AG-1 gave two kinds of gangliosides named acanthagangliosides I (1) and J (2). Their structures have been identified by negative FAB-MS.

As the aqueous sphere has been proposed to be an important source medium for the virus infection of land animals, the glycolipids of some aquatic organisms were examined for human influenza A virus-binding activity. Active compounds were not found among the eight echinoderm gangliosides, but two active non-sialylated glycoglycerolipids were isolated from an aquatic bacterium, Corynebacterium aquaticum. The structural formula of one of them, H632A, was elucidated to be 1-14-methyl-hexadecanoyl-3-alpha-D-galactopyranosyl-(1-->3)-6-(12-met hyl-tetradecanoyl)-1-alpha-D-mannopyranosyl]-sn-glycerol. The latter together with reported one elsewhere, S365A, 1-14-methyl-hexadecanoyl-3-[alpha-D-mannopyranosyl-(1-->3)-6-(12-meth yl-tetradecanoyl)-1-alpha-D-mannopyranosyl]-sn-glycerol, apparently bound to three human influenza viruses, A/PR/8/34 (H1N1), A/Aichi/2/68 (H3N2), and A/Memphis/1/71 (H3N2), exhibiting 7-12% (H632A) and 10-22% (S365A) of the activities of the control substances (Neu5Acalpha2-3-paragloboside and Neu5Acalpha2-6- paragloboside). Additionally, these glycolipids were assumed to have virus-neutralizing activities for the following two reasons: (i) The hemagglutination and hemolysis activities of the viruses were inhibited by the glycolipid. (ii) The leakage of a cytosolic enzyme (lactate dehydrogenase) from Madin-Darby canine kidney cells on virus infection was prevented by the glycolipids to nearly the same extent as by fetuin. This is the first evidence of the binding- and neutralizing-abilities of native glycoglycerolipids as to influenza viruses.

A galactocerebroside (BAC-4-4a) was obtained from its parent galactocerebroside molecular species (BAC-4) by using two types of reversed-phase HPLC column. The parent cerebroside BAC-4 has been isolated from less polar lipid fraction of CHCl(3)/MeOH extract of sea cucumber Bohadschia argus, together with known typical types of glucocerebroside molecular species. The structure of BAC-4-4a was determined on the basis of chemical and spectroscopic evidences as 1-O-(beta-D-galactopyranosyl)-(2S,3R,4E)-2[(2'R,15'Z)-2-hydroxytetracosenoylamino]-4-heptadecene-1,3-diol. This is the first report of isolation and structure determination of galactocerebroside from sea cucumber.

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.

A ganglioside molecular species [LLG-3 (1)] has been obtained from the water-soluble lipid fraction of the CHCl3/MeOH extract of the starfish Linckialaevigata. On the basis of chemical and spectroscopic findings, the structure of 1 has been elucidated. Negative-ion FABMS provided important information concerning both the structure of the sugar moiety and the molecular mass of the ganglioside. On the other hand, positive-ion FABMS/MS of [M + Na]+ ions obtained in the positive-ion FABMS of the ceramide lactoside (4) derived from 1 indicated the structure of the fatty acid chain of the ceramide moiety. 1 represents a new ganglioside molecular species possessing a 211-linked tandem-type disialosyl moiety.

Collision-induced dissociation (CID) spectra of sodium ion complexes ([M+Na]+ ions), produced by FAB-MS of methyl ester derivatives of ganglioside, indicate the length of the fatty acyl chain of the ceramide moieties without chemical degradation. In the case of a genuine ganglioside, only the fission of the glycosyl linkage of sialic acid was prominently observed.

The effect of Na+ ions on the fragmentation of tertiarybutoxycarbonyl (Boc) protected prolylproline (Pro-Pro) diastereomers, Boc-Pro-Pro and Boc-D-Pro-Pro, was studied in positive-ion fast atom bombardment (FAB) and tandem mass spectrometry. The formaiton of the [M+Na]+ ion for Boc-D-Pro-Pro was more predominant than that for Boc-Pro-Pro on the addition of sodium chloride in positive-ion FAB mass spectrometry, suggesting that Boc-D-Pro-Pro has a stronger Na+ ion affinity than Boc-Pro-Pro. In the collisional-activated decomposition mass spectra of the [M+Na]+ ions, the abundance of the [M+Na-C(CH3)3+H]+ ion, which is due to the loss of a tertiarybutyl group from the [M+Na]+ ion for Boc-D-Pro-Pro, was higher than that for Bos-Pro-Pro. These results indicate that the interaction of the Na+ ion with Boc-Pro-Pro is different from that with Boc-D-Pro-Pro in the FAB condition, and these diastereomers are distinguished by the addition of a Na+ ion in FAB and tandem mass spectrometry.

Three ganglioside molecular species, HPG-8, HPG-3, and HPG-1, have been obtained from the polar fraction of the chloroform/methanol extract of the sea cucumber Holothuriapervicax. The structures of these gangliosides have been determined on the basis of chemical and spectroscopic evidence. They represent new ganglioside molecular species. HPG-8 is a sulfated monosialo-ganglioside, while HPG-3 and HPG-1 are disialo-gangliosides possessing 24-linked tandem-type disialosyl moieties. These three gangliosides qualitative neuritogenic activity toward the rat pheochromocytoma cell line, PC-12 cells.

Five cerebrosides, CE-1-1, CE-1-2, CE-1-3, CE-3-1, and CE-3-2, and a ganglioside molecular species CG-1 have been obtained from the less polar and polar fractions, respectively, of the chloroform/methanol extract of the sea cucumber Cucumaria echinata. The structures of these glycosphingolipids have been determined on the basis of chemical and spectroscopic evidence. The cerebrosides show lethality toward brine shrimps. On the other hand, the ganglioside CG-1 exhibits neuritogenic activity toward the rat pheochromocytoma cell line, PC-12 cells.

Five cerebrosides, AS-1-1 (1), AS-1-2 (2), AS-1-3 (3), AS-1-4 (4), and AS-1-5 (5) were obtained from the CHCl3-MeOH extract of Garlic, the bulbs of Allium sativum L. (Liliaceae). On the basis of spectroscopic results, structures of 1-5 have been elucidated. Compounds 1, 2, and 5 were new cerebrosides. Compounds 3 and 4 were identified with the known glucocerebroside soya-cerebroside I and II, respectively, which have been previously obtained from soybean with ionophoretic activity. Positive ion FAB-MS/MS of the (M+Na)+ ion gave important information on the length of the fatty acyl chain of the ceramide moiety.

A sulfatide molecular species [LMG-1 (1)] have been obtained from the water soluble lipid fraction of the chloroform/methanol extract of the starfish Luidia maculata. On the basis of chemical and spectroscopic findings, the structure of 1 has been elucidated. Negative FAB mass spectrometry provided important information both on the structure of the sugar moiety and on the molecular mass of the sulfatide. 1 is, to the authors' knowledge, new sulfatide molecular species and first sulfatide obtained from starfish. In addition, 1 shows neuritogenic activity toward the rat pheochromocytoma cell line, PC-12 cell.

The hematoside analog 1 [NeuGcα(2→3)Galβ(1→4)Glcβ(1→1)Cer], which contains a phytosphingosine as a sphingoid base and an α-hydroxyfatty acid, has been synthesized. Coupling of the methyl (methyl 5-benzyloxyacetamido-4,7,8,9-tetra-O-acetyl-3,5-dideoxy-2-thio-D-glycero-α- and -β-D-galacto-2-nonulopyranosid)onate 5, prepared from the corresponding 5-acetamido derivative 2, with a lactose derivative 6 afforded sialolactoside 7, which was converted to the corresponding trichloroacetimidate 10. Glycosylation of 10 with the ceramide tribenzoate 12 gave the protected hematoside analog 13, which was deprotected to the hematoside analog 1.

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.

Collision-induced dissociation (CID) spectra of sodium ion complexed ([M+Na]+ ions) produced by FAB-MS of glycosphingolipids indicate the length of the fatty acyl chain of ceramide moieties without chemical degradation.

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 glycosyl inositolphosphoceramide-type ganglioside, CJP4, was obtained from the polar lipid fraction of the chloroform/methanol extract of the feather star Comanthus japonica. The structure of this ganglioside has been determined on the basis of chemical and spectroscopic evidence to be 9-O-methyl-(N-glycolyl-alpha-D-neuraminosyl)-(2-->11)-9-O-methyl-(N-glycolyl-alpha-D-neuraminosyl)-(2-->11)-9-O-methyl-(N-glycolyl-alpha-D-neuraminosyl)-(2-->3)-inositolphosphoceramide, which contains C(16)-sphingosine and C(22:0)-, C(24:0)-fatty acid. This is the first report on the isolation and structural elucidation of a trisialo-glycosyl inositolphosphoceramide-type ganglioside. Moreover, CJP4 exhibited neuritogenic activity toward the rat pheochromocytoma PC12 cells in the presence of nerve growth factor.

Two ganglioside molecular species [LG-1 (1) and LG-2 (5)] have been obtained from the water-soluble lipid fraction of the chloroform/methanol extract of the starfish Astropecten latespinosus. On the basis of chemical and spectroscopic findings, the structure of 1 and 5 have been elucidated. They are new ganglioside molecular species. Negative FAB mass spectrometry provided important information both on the structure of the sugar moiety and on the molecular mass of the gangliosides. Partial hydrolysis by hot water has proved useful for structure elucidation of the complex oligosaccharide moieties. In addition, the major ganglioside molecular species, LG-2 (5), shows antitumor activity against murine lymphoma L1210 cells in vitro.

[structure: see text] A novel diterpene, (-)-axinyssene, was isolated from the Japanese marine sponge Axinyssa sp. The structure of (-)-axinyssene was determined on the basis of spectroscopic and synthetic evidence to be 1-methyl-4-[(4E)-5',9'-dimethyl-1'-methylene-4',8'-decadienyl]-(4S)-cyclohexene. (-)- and (+)-axinyssene showed mild cytotoxicity against acute promyelocytic leukemia, HL-60 cells.

An ethanol (EtOH) extract of the soft coral (Sinularia sp.), collected in Okinawa, demonstrated a potent inhibitory effect on lipopolysaccharide (LPS)-induced tumor necrosis factor-alpha (TNF-alpha) production by murine macrophage-like cells (RAW264.7). The activity-guided purification of the EtOH extract resulted in the isolation of two norditerpenes, norcembrenolide (1) and sinuleptolide (2). These structures were identified from the spectroscopic data. Norcembrenolide (1) and sinuleptolide (2) inhibited TNF-alpha production in a dose-dependent manner, and showed a more potent effect than prednisolone at the concentration of 33 microg/ml. They also exhibited an inhibitory effect on nitric oxide (NO) production not influenced by cytotoxicity.

Four new cerebrosides, PA-0-1, PA-0-5, PA-2-5 and PA-2-6, were isolated from the two cerebroside mixtures, PA-0 and PA-2, obtained from the less polar fraction of the methanol extract of the sea cucumber Pentacta australis. The structures of these cerebrosides were determined on the basis of chemical and spectroscopic evidence. Another cerebroside, PA-1-4, isolated in a pure state from a different cerebroside mixture PA-1, was found to be identical with the known glucocerebroside CE-2c obtained from the related sea cucumber Cucumaria echinata of the same family. Reversed-phase HPLC was effective in isolating these cerebrosides, showing the very close similarity of their structures. An analysis of the mass spectrum of the dimethyl disulfide derivatives of cerebrosides was also useful for the determination of the double-bond position in the sea cucumber cerebroside.

Four new cembrane diterpenes (1—4) and fifteen known cembranoids (5—19) were isolated from an Okinawan soft coral Lobophytum crassum. The structures of these four new cembranoids were determined on the basis of spectroscopic evidence. In particular, the absolute stereochemistry of 1, 2, 5 and 6 were elucidated by the application of the modified Mosher's method and circular dichroism (CD) spectral data. The inhibitory effects of some isolates were evaluated on nitric oxide (NO) production against a murine macrophage-like cell line (Raw 264.7). Cembranoids consisting of α-methylene-γ-lactone, exhibited the significant effect on NO production.

Two ganglioside molecular species [GAA-6 (1) and GAA-7 (4)] have been obtained from the water-soluble lipid fraction of the chloroform/methanol extract of the whole bodies of the starfish Asterias amurensis versicolor Sladen. The structures of these ganglioside molecular species have been determined on the basis of chemical and spectroscopic findings. GAA-6 (1) is a starfish ganglioside molecular species resembling a mammalian brain ganglioside, GM3. In contrast, GAA-7 (4) is assigned the same structure as that of the main ganglioside[3] from Asterias amurensis[4] for the oligosaccharide moiety. Partial hydrolysis of oligosaccharide moieties with hot water or dilute acetic acid has proved useful for the structure elucidation of the ganglioside molecular species. Moreover, the Mayn ganglioside molecular species, GAA-7 (4), shows neuritogenic and growth-inhibitory activities towards the mouse neuroblastoma cell line (Neuro 2a). The structure-activity relationship of starfish gangliosides is also discussed.

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.