Cytotoxic 16-beta-[(D-xylopyranosyl)oxy]oxohexadecanyl triterpene glycosides from a Malagasy plant, Physena sessiliflora.

Brine shrimp lethality assay-guided separation of the MeOH extract of leaves of Physena sessiliflora, which is endemic to Madagascar, afforded eight triterpene glycosides, Physenoside S1-4 and 16-beta-[(d-xylopyranosyl)oxy]oxohexadecanyl homologues, Physenoside S5-8. Structural elucidation of these compounds was based on both spectroscopic analyses and chemical properties. Physenoside S7 and S8 have significant cytotoxic activities in the brine shrimp lethality assay.

[Studies on the constituents of cucurbitaceous plants].

I have an opportunity to have co-operative studies with Chinese group of Kunming Institute of Botany. Since then, I have investigated the chemical constituents of a number of Chinese plants of Araliaceae, Umbelliferae, Labiatae, Cucurbitaceae and other families. This review describes the structural elucidation of the cucurbitane, oleanane and dammarane glycosides, and their biological activities under the joint studies on cucurbitaceous plants, Bolbostemma, Hemsleya, Siraitia and Neoalsomitra species.

Antitumor agents. 261. 20(S)-protopanaxadiol and 20(s)-protopanaxatriol as antiangiogenic agents and total assignment of (1)H NMR spectra.

Angiogenesis is a critical step in tumor progression and involves several steps including endothelial cell (EC) proliferation, migration, and matrix remodeling. We investigated the antiangiogenic effects of 20( S)-protopanaxadiol ( 1) and 20( S)-protopanaxatriol ( 2), the sapogenins of two major ginseng saponins, in an angiogenesis model of human umbilical vein endothelial cells (HUVECs). These compounds inhibited the proliferative activity of HUVECs in a dose-dependent manner and have potential as anticancer drug candidates.

Phenylpropanoid and phenylethanoid derivatives from Kigelia pinnata DC. fruits.

Further phytochemical investigation of the fruits of Kigelia pinnata DC. has yielded a new phenylpropanoid derivative identified as 6-p-coumaroyl-sucrose (1) together with ten known phenylpropanoid and phenylethanoid derivatives (2-11) and a flavonoid glycoside (12). The structures of the isolated compounds were elucidated using various techniques of NMR and MS spectral analysis.

A new iridoid diglycoside from Clerodendrum chinense.

A new iridoid diglucoside, 5-O-beta-glucopyranosyl-harpagide, has been isolated from the aerial part of Clerodendrum chinense together with three known iridoid glucosides and six known cyclohexylethanoids. Their structures have been determined by analyses of spectroscopic data.

Triterpenoidal glycosides from Justicia betonica.

dFrom the aerial portion of Justicia betonica L., four triterpenoidal glycosides (justiciosides A-D) were isolated. Their structures were established through chemical and NMR spectroscopic analyses as olean-12-ene-1beta,3beta,11alpha,28-tetraol 28-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranoside, olean-12-ene-1beta,3beta,11alpha,28-tetraol 28-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranoside, 11alpha-methoxy-olean-12-ene-1beta,3beta,28-triol 28-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranoside, 11alpha-methoxy-olean-12-ene-1beta,3beta,28-triol 28-O-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranosyl-(1-->2)-beta-D-glucopyranoside, respectively.

Terpenic and phenolic glycosides from leaves of Breynia officinalis HEMSL.

From the leaves of Breynia officinalis, collected on Okinawa Island, six terpenic glucosides and six phenolic glycosides were isolated. Two of the terpenic glucosides were found to be known, and they were identified as turpinionoside B and betulalbuside A. The structures of the remaining terpenic glucosides were elucidated to be megastigmane glucosides, named breyniaionosides A-D, using spectroscopic analyses.

Aliphatic alcohol and iridoid glycosides from Asystasia intrusa.

An aliphatic alcohol glycoside (asystoside) and an iridoid diglucoside (3'-O-beta-D-glucopyranosyl-catalpol) were isolated from the aerial part of Asystasia intrusa along with benzyl beta-D-glucopyranoside, zizybeoside I, (6S,9R)-roseoside, verbascoside, ehrenoside, 6beta-hydroxyantirrhide, angeloside, catalpol, ajugol, 6-deoxycatalpol, and scutellarioside II. The structural elucidations were based on analyses of physical and spectroscopic data.

Phenylethanoid and iridoid glycosides from the Thai medicinal plant, Barleria strigosa.

A phenylethanoid (4-hydroxyphenylethyl 4-O-beta-D-glucopyranosyl-(1-->3)-O-alpha-L-rhamnopyranoside) and an iridoid (10-O-trans-coumaroyl-eranthemoside) were isolated from an entire Barleria strigosa plant together with verbascoside, isoverbascoside, decaffeoylverbascoside, (+)-lyoniresinol 3alpha-O-beta-D-glucoside, apigenin 7-O-alpha-L-rhamnosyl-(1-->6)-O-beta-D-glucoside, 7-O-acetyl-8-epi-loganic acid and (3R)-1-octen-3-ol-3-O-beta-D-xylosyl-(1-->6)-beta-D-glucoside. The structural elucidations were based on analyses of physical and spectroscopic data.

Tricin from a malagasy connaraceous plant with potent antihistaminic activity.

The bioassay-guided separation of a Malagasy plant, Agelaea pentagyna, led to the isolation of a flavonoid, tricin (1), with potent inhibitory activity toward exocytosis from antigen-stimulated rat leukemia basophils (RBL-2H3). The structure-activity relationships among structurally related natural and synthetic flavonoids are also discussed.

Activation of insulin receptors by lagerstroemin.

Lagerstroemin, an ellagitannin isolated from the leaves of Lagerstroemia speciosa (L.) Pers. (Lythraceae), was examined for its biological activities.

Lignan and megastigmane glycosides from Sauropus androgynus.

A lignan diglycoside, (-)-isolariciresinol 3alpha-O-beta-apiofuranosyl-(1-->2)-O-beta-glucopyranoside, and a megastigmane glucoside, sauroposide, were isolated from the aerial part of Sauropus androgynus together with (+)-isolariciresinol 3alpha-O-beta-glucopyranoside, (-)-isolariciresinol 3alpha-O-beta-glucopyranoside, (+)-syringaresinol di-O-beta-glucopyranoside, guanosine and corchoionoside C. The structural elucidations were bases on analyses of physical and spectroscopic data.

Iridoids from Kigelia pinnata DC. fruits.

From the fruits of Kigelia pinnata DC., a new furanone derivative formulated as 3-(2'-hydroxyethyl)-5-(2"-hydroxypropyl)-dihydrofuran-2(3H)-one (1), and four new iridoids named; 7-hydroxy viteoid II (2), 7-hydroxy eucommic acid (3), 7-hydroxy-10-deoxyeucommiol (4) and 10-deoxyeucommiol (5) have been isolated together with seven known iridoids, jiofuran (6), jioglutolide (7), 1-dehydroxy-3,4-dihydroaucubigenin (8), des-p-hydroxybenzoyl kisasagenol B (9), ajugol (10), verminoside (11) and 6-trans-caffeoyl ajugol (12). The structures of the isolated compounds were characterized by different spectroscopic methods.

Anticarcinogenic activity of natural sweeteners, cucurbitane glycosides, from Momordica grosvenori.

To search for cancer chemopreventive agents from natural resources, many phytochemicals and food additives have been screened. Consequently, two natural sweeteners, mogroside V and 11-oxo-mogroside V isolated from the fruits of Momordica grosvenori, exhibited strong inhibitory effect on the primary screening test indicated by the induction of Epstein-Barr virus early antigen (EBV-EA) by a tumor promoter, 12-O-tetradecanoylphorbol-13-acetate (TPA). These sweet glycosides, having cucurbitane triterpenoid aglycon, exhibited the significant inhibitory effects on the two-stage carcinogenesis test of mouse skin tumors induced by peroxynitrite (ONOO-) as an initiator and TPA as a promoter.

Iridoid and phenolic diglycosides from Canthium berberidifolium.

An iridoid diglycoside, 6-O-beta-D-apiofuranosyl-mussaenosidic acid, and four phenolic diglycosides, canthosides A-D, were isolated from the aerial part of Canthium berberidifolium, along with seven known compounds. Structural elucidations were based on analyses of spectroscopic data.

ent-Kaurane diterpenoid glycosides from a Malagasy endemic plant, Cussonia vantsilana.

Four ent-kaurane diterpenoid glycosides, cussovantosides A-D, were isolated from the dried leaves of Cussonia vantsilana Baker, together with six known compounds. The structures of the compounds were deduced on the basis of their physical and spectral data.

Cussosaponins A-E, triterpene saponins from the leaves of Cussonia racemosa, a Malagasy endemic plant.

Five new triterpene saponins, cussosaponins A (2), B (3), C (4), D (5), and E (6), were isolated from the dried leaves of Cussonia racemosa BAKER. The structures of these new compounds were deduced on the basis of chemical and spectroscopic evidence.

A new ent-kaurane diterpenoid glycoside from the leaves of Cussonia bojeri, a Malagasy endemic plant.

A new ent-kaurane diterpene glycoside, beta-D-glucopyranosyl 17-hydroxy-ent-kauran-19-oate-16-O-beta-D-glucopyranoside (4) was isolated from the dried leaves of Cussonia bojeri SEEM., together with four known compounds identified as 16beta,17-dihydroxy-kauran-19-oic acid (1), beta-D-glucopyranosyl 16beta,17-dihydroxy-(-)-kauran-19-oate (2), paniculoside IV (3), and rutin (5). The structure of 4 was deduced on the basis of chemical and spectroscopic evidence.

Pregnane and pregnane glycosides from the Malagasy plant, Cynanchum aphyllum.

A new 8,14-seco-pregnane type of steroid called cynaphyllogenin and its eight glycosides, cynaphyllosides A-H, were isolated from the aerial parts of Cynanchum aphyllum. The structures of these compounds were elucidated based on chemical and spectroscopic evidence.

Iridoid glucosides from Thunbergia laurifolia.

Two iridoid glucosides, 8-epi-grandifloric acid and 3'-O-beta-glucopyranosyl-stilbericoside, were isolated from the aerial part of Thunbergia laurifolia along with seven known compounds, benzyl beta-glucopyranoside, benzyl beta-(2'-O-beta-glucopyranosyl) glucopyranoside, grandifloric acid, (E)-2-hexenyl beta-glucopyranoside, hexanol beta-glucopyranoside, 6-C-glucopyranosylapigenin and 6,8-di-C-glucopyranosylapigenin. Structural elucidation was based on the analyses of spectroscopic data.

Stilbene and 2-arylbenzofuran glucosides from the rhizomes of Schoenocaulon officinale.

Two stilbene glucosides, oxyresveratrol 2-O-beta-glucopyranoside and resveratrol 3,4'-O,O'-di-beta-D-glucopyranoside, and a 2-arylbenzofuran glucoside, schoenoside, were isolated from the rhizomes of Schoenocaulon officinale, along with five known compounds, oxyresveratrol 3'-O-beta-D-glucopyranoside, oxyresveratrol, resveratrol 3-O-beta-D-glucopyranoside, mulberroside A and moracin M 3'-O-beta-D-glucopyranoside. The structural elucidations were based on analyses of both physical and spectroscopic data.

Clerodane and labdane diterpene glycosides from a Malagasy endemic plant, Cussonia racemosa.

Four clerodane glycosides, cussosides A-D, and one labdane glycoside, cussoside E were isolated from the dried leaves of Cussonia racemosa, along with two known flavonol glycosides identified as rutin and kaempferol rutinoside. The structures of the compounds were deduced on the basis of their physical and spectral data.

Phenolic glycosides from Barnettia kerrii.

From the leaves and branches Barnettia kerrii, two verbascoside derivatives (6"-O-acetylverbascoside and 4"'-O-acetylverbascoside), as well as two phenolic glycosides (khaephuosides A and B) were isolated together with 15 known compounds. The structural elucidations were based on analyses of spectroscopic data.

Phenolic glycosides from Markhamia stipulata.

From the leaves and branches of Markhamia stipulata, five verbascoside derivatives (markhamiosides A-E), and one hydroquinone derivative (markhamioside F) were isolated together with 13 known compounds. Their structural elucidation was based on analyses of chemical and spectroscopic data.

Iridoid and phenolic glycosides from Morinda coreia.

From the leaves and branches of Morinda coreia, six compounds [yopaaosides A-C, 10-O-acetylmonotropein, 6-O-acetylscandoside and 3,4,5-trimethoxyphenyl 1-O-beta-apiofuranosyl (1"-->6')-beta-glucopyranoside] have been isolated together with five known compounds. Structural elucidations were based on analyses of physical and spectroscopic data.