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Two polyacetylene glycosides, lobetyol 9-O-glc(6)-(1)rha (pratialin-A) and lobetyol 9-O-glc(6)-(1)glc(6)-(1)glc (pratialin-B), were isolated from Pratia nummularia (Campanulaceae) callus and hairy root cultures and their chemical structures were determined by analysis of spectroscopic data. From the methanol extract of the hairy root cultures, together with the known polyacetylene constituents lobetyol, lobetyolin, and lobetyolinin, tryptophan was also isolated. This report is the first example of the isolation and structure elucidation of rutinoside (pratialin-A) and triglucoside (pratialin-B) derivatives of polyacetylene constituents.

A further investigation of the leaves and stems of Saprosma scortechinii afforded 13 compounds, of which 10 are new compounds. These were elucidated as the bis-iridoid glucosides, saprosmosides G (1) and H (2), the iridoid glucoside, 6-O-epi-acetylscandoside (3), and the anthraquinones, 1-methoxy-3-hydroxy-2-carbomethoxy-9,10-anthraquinone (4), 1-methoxy-3-hydroxy-2-carbomethoxy-9,10-anthraquinone 3-O-β-primeveroside (5), 1,3-dihydroxy-2-carbomethoxy-9,10-anthraquinone 3-O-β-primeveroside (6), 1,3,6-trihydroxy-2-methoxymethyl-9,10-anthraquinone (7), 1-methoxy-3,6-dihydroxy-2-hydroxymethyl-9,10-anthraquinone (8), 1,3,6-trihydroxy-2-hydroxymethyl-9,10-anthraquinone 3-O-β-primeveroside (9), and 3,6-dihydroxy-2-hydroxymethyl-9,10-anthraquinone (10). Structure assignments for all compounds were established by means of mass and NMR spectroscopies, chemical methods, and comparison with published data. The new anthraquinones were derivatives of munjistin and lucidin., Chemical & Pharmaceutical Bulletin v.50(8) p.1035-1040, 2002

A flavone derivative 5,2′-dihydroxy-6,7,8,3′-tetramethoxyflavone identified by 1 H-, 13 C-NMR, FABMS, together with two known phenolics skullcapflavone I and acteoside ( 3 ), were isolated from Scutellaria baicalensis transformed roots (clone C) into which the β-glucuronidase gene had been integrated by the infection with Agrobacterium rhizogenes A13. Another clone of transformed roots (clone W) was also induced by infection with A. rhizogenes ATCC 15834 (wild type). Both clones C and W, cultured in phytohormone-free BF liquid medium, produced 3 at a high content (maximum; clone C: 1.81% and clone W: 2.96% of tissue dry weight) under the light and dark conditions. The contents of glucuronide-type flavonoids, such as baicalin and wogonin 7- O -glucuronide in clone W, were almost three times higher than those in clone C. Compound 3 , which was not detected in the intact plant roots, also accumulated in leaf (0.23% dry weight) and root (0.68% dry weight) parts of in vitro cultured plantlets.

Mono-altro--cyclodextrin 1 ,a -cyclodextrin with one of the seven glucose units being configurationally changed to an altrose, is shown to be a flexible host undergoing a distinct conformational change within its altropyranose geometry upon intracavity inclusion of adamantanecarboxylate, thus representing an induced-fit model of binding rather than one following the rigid lock-and-key type pattern. © 1999 Elsevier Science Ltd. All rights reserved.

The CHCl3 extract of the root of Angelica japonica showed high inhibitory activity against human gastric adenocarcinoma (MK-1) cell growth. From this extract, a new furanocoumarin named japoangelone and four furanocoumarin ethers of falcarindiol, named japoangelols A-D, were isolated together with caffeic acid methyl ester, four polyacetylenic compounds (panaxynol, falcarindiol, 8-O-acetylfalcarindiol, and (9Z)-1,9-heptadecadiene-4,6-diyne-3,8,11-triol), eight coumarins (osthol, isoimperatorin, scopoletin, byakangelicin, xanthotoxin, bergapten, oxypeucedanin methanolate, and oxypeucedanin hydrate), and two chromones (3'-O-acetylhamaudol, and hamaudol). The structures of the new isolates were determined based on spectral evidence. The ED50 of isolates against MK-1, HeLa, and B16F10 cell lines are reported.

Five new chromone components were isolated from the gel of Aloe vera leaves. Their structures have been established as 8- C -glucosyl-noreugenin, 4′- O -glucosyl-isoaloeresin DI, 4′– O -glucosyl-isoaloeresin DII, 8- C -glucosyl-(2′- O -cinnamoyl)-7- O -methylaloediol A and 8- C -glucosyl-(2′- O -cinnamoyl)-7- O -methylaloediol B, from spectroscopic studies.

Callus tissue of Aloe barbadensis grown in the dark produced two new tetrahydroanthracene glucosides, 3,4-dihydro-2,4,8,9-tetrahydroxy-6-methyl-1(2H)-anthracenone-4- O - β -d-glucopyranoside and 3,4-dihydro-2-methoxy-4,8,9-trihydroxy-6-methyl-1(2H)-anthracenone-4- O - β -d-glucopyranoside. The effect of light on the formation of tetrahydroanthracene glucosides in the calli is discussed.

The leaves of Aloe vera afforded, together with 10-hydroxyaloins A and B, a new pair of diastereoisomeric C -glucosylanthrones whose structures were established as 8- O -methyl-7-hydroxyaloin A and 8- O -methyl-7-hydroxyaloin B from spectroscopic studies. © 1997 Elsevier Science Ltd. All rights reserved

Cytotoxicities for lobatosides B—E and actinostemmosides B—F, isolated from Actinostemma lobatum , were evaluated against a panel of ca 60 human cancer cell lines. Lobatosides B—E ( 1–4 ) were cytotoxic (GI 50 ≤ 1 × 10 −4 M) against all tumor cell lines; 4 showed potent cytotoxicity especially against A-549, SK-MEL-5, and SW-620 cell lines with GI 50 values of 0.14, 0.14, and 0.36 μM, respectively.

Three new chromone components, 8-C-glucosyl-7-O-methyl-(S)-aloesol, isoaloeresin D and aloeresin E were isolated from the leaves of Aloe vera. Their structures have been established from spectroscopic studies; the structures of 8-C-glucosyl-7-O-methyl-(S)-aloesol, isoaloeresin D and aloeresin E were shown to be 8-C-β- d - glucopyranosyl -2-[(S)-2- hydroxy]propyl-7-methoxy-5-methylchromone , 8-C-β- d -[2′-O-(E)-p- coumaroyl]glucopyranosyl -2-[(S)-2- hydroxy]propyl-7-methoxy-5-methylchromone and 8-C-β- d -[2′-O-(E)- cinnamoyl]glucopyranosyl -2-[(S)-2- hydroxy]propyl-7-methoxy-5-methylchromone , respectively. The inhibitory action of these compounds against tyrosine oxidation by mushroom tyrosinase was examined.

The stereostructures of cumingianosides A-F, a series of triterpene glucosides with a 14,18-cycloapoeuphane skeleton, have been established by X-ray crystallographic analysis on an aglycone [1c] the acid hydrolysate of cumingianoside A [1], which is a potent cytotoxic triterpene against MOLT-4 human leukemia cells with an EC50 value of < 0.00625 microM. The 14,18-cyclopropane ring in cumingianoside A [1] was opened under acidic conditions in two different directions to give compounds with an apoeuphane skeleton and a dammarane skeleton. Furthermore, it was found that subsequent hydrolysis yielded not only an aglycone with an apoeuphane skeleton [1c] but also an apo-rearrangement product [1d].

Forty-two dihydroseselins based on the structure of suksdorfin (1) were synthesized in order to evaluate their anti-HIV activity. These synthetic derivatives include 3',4'-di-O-acyl- and 3'- or 4'-O-acyl-cis-dihydroseselins (8-21) and 3',4'-trans-dihydroseselins with O-acyl and/or O-alkyl groups at the 3' and 4' positions (6, 22-43). Two 4'-azido (44, 45) and three 4'-alkylamido (46, 48, 49) derivatives were also prepared. By using optically pure reagents, three pairs of diastereoisomers were synthesized and separated as optically pure compounds (14, 15; 16, 17; 38, 39). Together with the above synthetic derivatives, seselin (3) and (+/-)-cis-(4), (+)-cis- (5), and (+/-)-trans-dihydroseselin-3',4'-diol (7) were also tested for their in vitro anti-HIV activity. An optically pure compound, 3',4'-di-O-(-)-camphanoyl-(+)-cis-khellactone (16), showed potent inhibitory activity and remarkable selectivity against HIV replication. The EC50 value and in vitro therapeutic index (TI) of 16 are 4 x 10(-4) microM and 136,719, respectively, which are better than those shown by AZT in the same assay. In addition, compound 16 is also active against HIV replication in a monocytic cell line and in peripheral blood mononuclear cells (PBMCs). Our in vitro assay indicated that, like compound 1, compound 16 is not an inhibitor of HIV-1 reverse transcriptase. Moreover, the anti-HIV activity of 16 is stereoselective as its three diastereoisomers (17, 38, 39) are at least 10,000 times less active. Since other synthetic dihydroseselin derivatives with different substituents or without any substituents are inactive or are active only at much higher concentration, the antiviral potency of 16 could be associated with the camphanoyl moieties of its structure. Therefore, compound 16 represents a unique coumarin structure with promising anti-HIV activity.

Two new and two known complex flavan-3-ols, containing an additional phenylpropanoid (C 6 –C 3 ) unit in the molecule, have been isolated from the leaves of Castanopsis hystrix . The structures including absolute stereochemistry were elucidated on the basis of spectroscopic evidence and also by synthesis. In addition, comparison of the CD spectral data of these compounds with those of previously known complex flavan-3-ols, cinchonains, has led to the revision of their structures.

In conjunction with a chemotaxonomic analysis of tannins in fagaceous plants, a new hydrolysable tannin (castanopsinin I) containing a triterpenoid gly

Four novel antiproliferative furanocoumarin ethers of falcarindiol, named japoangelols A (8.5), B (7.2), C (7.4), and D (8.4), were isolated from the root of Angelica japonica together with panaxynol (0.3), falcarindiol (3.2), (9Z)-1,9-heptadecadiene-4,6-diyne-3,8,11-triol (2.2), and 8-acetoxyfalcarinol (3.2). Structures were established from the spectroscopic evidence, and the inhibitory activities (ED50, microgram/ml, shown in the parentheses) were evaluated using the MTT assay.

Six new triterpene glucosides, cumingianosides A-F (1-6) as well as trisnor- and a tetranortriterpene glucoside, cumindysosides A (7) and B (8), wiht a 14,18-cycloapoeuphane-type skeleton have been isolated from Dysoxylum cumingianum as antileukemic principles. The structures were established on the basis of chemical and spectroscopic evidence. Among them, compounds 1 and 3 exhibited potent selective cytotoxicity against MOLT-4 human leukemia cell with ED 50 of

Two new gypsogenin glycosides, named lobatosides I and J, and one oleanolic acid glycoside, lobatoside K, were isolated from the seed of Actinostemma lobatum MAXIM. (Cucurbitaceae), and thier structures were elucidated to be as follows based on chemical and spectral evidence.Lobatoside I : 3-O-[O-β-D-galactopyranosyl-(1→2)-β-D-glucopyranosyluronic acid]gypsogenin 28-{O-β-D-glucopyranosyl-(1→3)-[O-β-D-xylopyranosyl-(1→4)]-O-α-L-rhamnopyranosyl-(1→2)-β-D-fucopyranosyl}ester.Lobatoside J : 3-O-[O-β-D-galactopyranosyl-(1→2)-β-D-glucopyranosyluronic acid]gypsogenin 28-{O-β-D-xylopyranosyl-(1→3)-O-β-D-xylopyranosyl-(1→4)-[O-β-D-glucopyranosyl-(1→3)]-O-α-L-rhamnopyranosyl-(1→2)-β-D-fucopyranosyl}ester.Lobatoside K is an oleanolic acid glycoside. The structure of the sugar moiety is the same as that of lobatoside I.

Cumindysoside A, a novel trisnortriterpene glucoside with a 14, 18-cycloapoeuphane-type skeleton, has been isolated from Dysoxylum cumingianum as a cytotoxic principle. Its structure was established from spectroscopic evidence.

Two novel hydrolyzable tannins, alienanins A (5) and B (13), have been isolated from the leaves of Quercus aliena GLUME (Fagaceae), and their structures were elucidated on the basis of chemical and spectroscopic evidence to be dimeric C-glycosidic ellagitannins in which the hexahydroxydiphenoyl ester group is linked to the C-glycosidic C-1 atom through a carbon to carbon linkage. In addition, the structure elucidation of the monomeric C-glycosidic ellagitannin, epipunicacortein A (1), is also described briefly.

A reaction of β-cyclodextrin with β-naphthylsulfonyl chloride in alkaline aqueous acetonitrile gave only one isomer (3 A ,3 C ,3 E -trisulfonate, 17.8%) of five 3,3,3-tri-O-sulfonyl-β-cyclodextrins. The isomer was converted to 3 A ,6 A :3 C ,6 C :3 E ,6 E -trianhydro-β-cyclodextrin, the structure of which was assigned by comparing its spectral and HPLC data of the trianhydro-β-cyclodextrin with those of all authentic 3,6:3,6:3,6-trianhydro-β-cyclodextrins prepared by the reactions of known 6-tri-O-sulfonylated β-cyclodextrins with aqueous alkali

The structures of the C-glycosidic ellagitannins, castalagin, vescalagin, casuarinin and stachyurin, have been revised to 1-4 respectively, on the basis of two-dimensional nuclear Overhauser effect (NOE) spectroscopy and NOE difference spectroscopy. Furthermore, the structures of some related C-glycosidic tannins were re-examined by using similar techniques, and it was concluded that the configuration at the glucose C-1 position in all hitherto known C-glycosidic tannins must be revised.

The MeOH extract of the fruits of Bupleurum rotundifolium showed inhibitory activity against human gastric adenocarcinoma (MK-1) cell growth. Bioactivity-guided fractionation of the MeOH extract led to the isolation of four new triglycosides of 13beta,28-epoxy oleanane-type triterpenes, named rotundiosides O, Q, S and T; 12 new glycosides of oleanane-type triterpenes, named rotundiosides J-N, P, R, U-Y, and others; echinocystic acid 3-O-sulfate; and three known oleanane-type triterpene glycosides, rotundiosides A, F and G. The structures of the new isolates were determined based on chemical and spectroscopic evidence. The GI(50) of isolates against MK-1, HeLa and B16F10 cell lines are reported.

The antiproliferative constituents in the MeOH extract from the aerial parts of Centella asiatica were investigated. Activity-guided fractionation of MeOH extract resulted in the isolation of ursolic acid lactone, ursolic acid, pomolic acid, 2alpha,3alpha-dihydroxyurs-12-en-28-oic acid, 3-epimaslinic acid, asiatic acid, corosolic acid, and rosmarinic acid. Antiproliferative activity of the isolated compounds against human gastric adenocarcinoma (MK-1), human uterine carcinoma (HeLa), and murine melanoma (B16F10) cells was estimated.

(+)-1(R)-Coclaurine (1) and (-)-1(S)-norcoclaurine (3), together with quercetin 3-O-beta-D-glucuronide (4), were isolated from the leaves of Nelumbo nucifera (Nymphaceae), and identified as anti-HIV principles. Compounds 1 and 3 demonstrated potent anti-HIV activity with EC50 values of 0.8 and0.8 microg/mL, respectively, and therapeutic index (TI) values of125 and25, respectively. Compound 4 was less potent (EC50 2 microg/mL). In a structure-activity relationship study, other benzylisoquinoline, aporphine, and bisbenzylisoquinoline alkaloids, including liensinine (14), negferine (15), and isoliensinine (16), which were previously isolated from the leaves and embryo of Nelumbo nucifera, were evaluated for anti-HIV activity. Compounds 14-16 showed potent anti-HIV activities with EC50 values of0.8 microg/mL and TI values of9.9,8.6, and6.5, respectively. Nuciferine (12), an aporphine alkaloid, had an EC50 value of 0.8 microg/mL and TI of 36. In addition, synthetic coclaurine analogs were also evaluated. Compounds 1, 3, 12, and 14-16 can serve as new leads for further development of anti-AIDS agents.

A new megastigmane diglycoside was isolated from the leaves of Carallia brachiata. The structure was determined by spectroscopic methods as 3-hydroxy-5,6-epoxy-beta-ionol -3-O-beta-apiofuranosyl-(1--6)-beta-glucopyranoside (1). Additionally, 29 known compounds consisting of two megastigmanes, one 1,2-dithiolane derivative, seven aromatic compounds, five condensed tannins, 12 flavonoids, and two glyceroglycolipids were isolated and identified.

The MeOH extract of the fruits of Bupleurum rotundifolium showed inhibitory activity against human gastric adenocarcinoma (MK-1) cell growth (GI(50): 6.25 microg/ml). From this extract, 10 new ursane-type triterpene glycosides viz. three 3-O-triosides (called rotundifoliosides A, I, and J) of 13beta,28-epoxy-3beta,16alpha-dihydroxyurs-11-ene, two (G and H) of 13beta,28-epoxy-3beta,16alpha,23-trihydroxyurs-11-ene, two (E and F) of 13beta,28-epoxy-3beta,16alpha,21beta-trihydroxyurs-11-ene, two (B and C) of 3beta,11alpha,16alpha,28-tetrahydroxyurs-12-ene, and one (D) of 3beta,11alpha,28-trihydroxy-15alpha,16alpha-epoxyurs-12-ene were isolated in addition to 16 new oleanane-type triterpene glycosides (rotundiosides J-Y), echinocystic acid 3-O-sulfate and 3 known oleanane-type triterpene glycosides (rotundiosides A, F and G). The isolation, structures and antiproliferative activity of the new ursane-type triterpene glycosides against MK-1, human uterus carcinoma (HeLa), and murine melanoma (B16F10) cell lines are described with some comments on the structural requirements for their activity.

Production and accumulation of catechin dimer quinones during tea fermentation were chemically confirmed for the first time by trapping as phenazine derivatives. Direct treatment of the fermented tea leaves with o-phenylenediamine yielded five phenazine derivatives (8-12) of o-quinones of an epigallocatechin dimer and its galloyl esters (13-16), in which two flavan units were linked at the B-rings through a C-C bond. Atrop isomerism of the biphenyl bonds was shown to be the R configuration, suggesting that the o-quinone dimers were generated by stereoselective coupling of monomeric quinones. The total concentration of the phenazine derivatives in the o-phenylenediamine-treated tea leaves was higher than that of theaflavins. In contrast, phenazine derivatives of monomeric quinones of epigallocatechin were not isolated. When the fermented tea leaves were heated, the quinone dimers were converted to theasinensins, which are constituents of black tea, suggesting that theasinensins are generated by reduction of the quinone dimers during the heating and drying steps in black tea manufacturing.

Biodisposition of FITC-labeled aloemannan (F-AM) with the homogenate from some organs in mice was demonstrated. F-AM was metabolized only by the mucosa from the large intestine into smaller molecules that were effectively absorbed in mice. The homogenate from the other tissues did not affect the metabolism of F-AM. The degraded product (1) of F-AM after incubation with 10% feces homogenate for 24 h was chromatographed on a highly porous polymer and a Sephadex LH-20 column to provide an FITC-degraded fraction (2), which was shown to have a molecular weight of 800 D on Sephadex G-25 gel permeation. Metabolite 2 was examined by physicochemical methods and shown to be a mixture of FITC-hexose and -2 hexose on FAB-MS. An FITC-degraded fraction (3) with a molecular weight of 3 KD was obtained by 6-h incubation with 10% feces homogenate on Sephadex G-25 column chromatography and was shown to be a mixture of FITC-9 and 12 × hexose on TOF-MS.

An ellagic acid derivative, 3,3′-di- O -methylellagic acid 4-(5″-acetyl)- α - l -arabinofuranoside, and two iridoid glucosides, 6 α -dihydrocornic acid and 6 β -dihydrocornic acid, were isolated from Cornus capitata adventitious roots cultured in Murashige–Skoog (Murashige, T., Skoog, F., 1962. A revised medium for rapid growth and bioassays with tobacco tissue cultures. Physiol. Plant. 15, 473–487) liquid medium containing 10 μM CuSO 4 . Three known related metabolites, i.e. stenophyllin H1, dihydrocornin and cornin were also produced in the root cultures. The chemical structures were characterized by analysis of spectroscopic data.

Three novel diterpenes, dysokusones A (1), B (2), and C (3), were isolated from the stem of Dysoxylum kuskusense as cytotoxic substances. The structures were established by spectroscopic examinations. Compounds 1, 2, and 3 were cytotoxic toward HL-60(TB) cells with EC50 values of 2.25, 6.35, and 2.37 microM, respectively. Compound 1 also displayed cytotoxicity against K-562 and NCI-H522 cells with EC50 values of 5.04 and 4.80 microM, respectively.

Four novel antiproliferative furanocoumarin ethers of falcarindiol, named japoangelols A (8.5), B (7.2), C (7.4), and D (8.4), were isolated from the root of Angelica japonica together with panaxynol (0.3), falcarindiol (3.2), (9Z)-1,9-heptadecadiene-4,6-diyne-3,8,11-triol (2.2), and 8-acetoxyfalcarinol (3.2). Structures were established from the spectroscopic evidence, and the inhibitory activities (ED50, microgram/ml, shown in the parentheses) were evaluated using the MTT assay.

Treatment of cumingianosides and cumindysoside A, which possess a 14,18-cycloapotirucallane skeleton, with p-toluenesulfonic acid in CH 2 Cl 2 yielded new triterpene glucosides. Cumingianoside A (1) gave 10 and 11, along with cumingianoside Q (5). The structures of 10 and 11 were determined on the basis of spectral examination and contained a dammar-13(17)-ene and a 17(R),23(R)-epoxydammarane skeleton, respectively. Cumingianoside C (2) afforded, together with cumingianoside P (6), products 12 and 13, which were similar to 10 and 11, respectively. With a short reaction time at room temperature, cumingianoside E (3) yielded cumingianoside D (4). In contrast, when 3 was treated with p-toluenesulfonic acid in CH 2 Cl 2 overnight at 5 °C, it gave two products, 9 and 14. Extensive spectroscopic examination revealed that 9 possessed a dammar-12-ene skeleton, while 14 was a pentacyclic tetranortriterpene glucoside with a novel skeleton. Cumindysoside A (8) gave a product (15) similar to 14. The cytotoxicities of 9-15 were evaluated against a panel of 58 human tumor cell lines. Compounds 11-15 exhibited potent cytotoxicity with log GI 50 values ranging from -7.11 to -4.94, especially against leukemia and colon-tumor cell lines

Nine new triterpene glucosides, named cumingianosides G-O (4-7, 9, 12-15), containing a 14,18-cycloapotirucallane-type skeleton were isolated from a cytotoxic fraction of the leaves of Dysoxylum cumingianum. The structures of the new compounds were established on the basis of chemical and spectral examinations. Evaluation of the cytotoxic activity of cumingianosides G-O showed that cumingianoside M exhibited significant (< 4 microM) cytotoxicity, especially against leukemia and melanoma cell lines.

Detailed chemical studies on the cytotoxic fraction from the leaves of Dysoxylum cumingianum have resulted in the isolation of two new triterpene glucosides, cumingianosides P (18) and Q (19), with an apotirucallane-type skeleton. The structures of 18 and 19 were determined by spectral examinations, and by conversion of cumingianosides C (3) and A (1) into 18 and 19, respectively. The cytotoxicities of cumingianosides P and Q against over 50 human cancer cell lines were evaluated. Cumingianoside P exhibited significant (EC504 microM) cytotoxicity against 37 human cancer cell lines. Among them, the UO-31 (renal cancer) cell line was the most sensitive to this compound (EC50 0.267 microM). In contrast, cumingianoside Q showed selective cytotoxicity against NCI-H522 (non-small cell lung cancer) cells with an EC50 value of 1.67 microM, and exhibited no cytotoxicity (EC5010 microM) against most of the remaining cancer cell lines.

Significant restriction of the rotation of an intermolecular guest upon binding into a distorted cyclodextrin cavity has been observed for the first time.

The unique hydrated biscyclohexenetrione structures (1)–(4) of carpinins A–D, the metabolites of hexahydroxydiphenic acid esters (ellagitannins) isolated from the leaves of Carpinus japonica, are described.

Methyl derivatives of indan-1-one were prepared as models to aid in interpreting the carbon-13 nuclear magnetic resonance (13C-NMR) spectra of pterosin-sesquiterpenes which were isolated from bracken fern, Pteridium aquilinum var. latiusculum. The chemical shifts of the carbons of the methylindan-1-ones were assigned by the proton decoupling technique. All the 13C-NMR signals of the pterosin-sesquiterpenes were assigned by means of selective proton decouplings, and from the 13C-1H long-range couplings and 13C chemical shifts of the model compounds..

Eight bayogenin glycosides, lobatosides A-H, were isolated from the herb of Actinostemma lobatum MAXIM.(Cucurbitaceae). The isolation of lobatosides A-H and the structures of lobatosides A, C, D and H are described.Lobatoside A is 3-O-[α-L-arabinopyranosyl-(1→2)-β-D-glucopyranosyl]bayogenin (2β, 3β, 23-trihydroxyolean-12-en-28-oic acid). Lobatosides C, D and H are dicrotalic acid (3-hydroxy-3-methylglutaric acid) esters of the 28-[α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl] ester, 28-[β-D-glucopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl] ester and 28-[β-D-xylopyranosyl-(1→3)-α-L-rhamnopyranosyl-(1→2)-α-L-arabinopyranosyl] ester of lobatoside A, respectively. Dicrotalic acid is linked at one end to the C4-hydroxyl group of the α-L-arabinopyranosyl group in the C3-linked sugar moiety, and at the other end to the C4-hydroxyl group of the α-L-rhamnopyranosyl group in the ester-linked sugar moiety to form a macrocyclic structure ("cyclic bisdesmoside"). Lobatoside H was proved to be identical with tubeimoside I isolated from the tuber of Bolbostemma paniculatum (MAXIM.) FRANQUET (Cucurbitaceae).

Minor cardenolide glycosides, including 3-O-(4, 6-dideoxy-3-O-methyl-Δ3-D-hexosulosyl)-affinogenin Ld (affinoside O), 3-O-(4, 6-dideoxy-3-O-methyl-D-allosyl)-affinogenin H (affinoside N), and Δ16-affinoside M (affinoside I) were isolated along with the 3, 16-diacetate of 2β, 3β, 14, 16β-tetrahydroxy-11-oxo-5β, 14β-card-20(22)-enolide (affinogenin D-VI), from the leaves of Anodendron affine DRUCE. The conformations of rings A and B in the doubly linked glycosides and free aglycones are discussed.

A novel procyanidino-ellagitannin, mongolicanin (1), has been isolated, together with three new tannins, mongolinin A (4), acutissimin C (7) and vescalagin carboxilic acid (8), from the bark of Quercus mongolica var. grosseserrata (Fagaceae), and the structure of these compounds were established on the basis of physicochemical data.

From the dried herb of Actinostemma lobatum MAXIM. (Cucurbitaceae), two new baccharane-type triterpene glycosides, actinostemmosides E and F, were isolated. The structure of actinostemmoside F was elucidated mainly on the basis of 13C-13C-nuclear magnetic resonance (NMR) correlation spectrometry as the 3-O-β-D-galactopyranosyl-(1→2)-α-L-arabinopyranoside of 3β, 17β, 21, 26, 30-pentahydroxybacchar-24-ene. The structure of actinostemmoside E was determined as the 3-O-β-D-galactopyranosyl-(1→2)-β-D-glucopyranoside of 3β, 17β, 21, 26-tetrahydroxybacchar-24-ene by comparison of the 1H- and 13C-NMR spectra with those of actinostemmoside F.

Two compounds, positive (red) to the Ehrlich reagent and predominant in the methanol extracts of the fresh rhizomes of Dioscorea gracillima MIQ., were isolated. Their structures were established as 26-O-β-D-glucopyranosyl 22-methoxyfurost-5-ene-3β, 26-diol 3-O-β-chacotrioside (I), mp 187-191°(decomp.), [α]D-95.6°, and its 22-hydroxy analog (I'), mp 190-196°(decomp.), [α]D-79.8°, the furostanol bisglycosides corresponding to 25D-spirost-5-en-3β-ol (diosgenin) 3-O-β-chacotrioside (dioscin) (III), the major component of the stored materials. I is regarded as an artifact formed from I', and I'and I are named proto-dioscin and methyl proto-dioscin, respectively. Smilax-saponin B, which had been assigned a structure, diosgenin hexaglycoside, was identical with I and the structure is revised. Among the Ehrlich positive compounds in the methanol extracts of the fresh rhizomes of D. septemloba THUNB., the major, mp 249-251°(decomp.), [α]D-76.9°, was isolated and characterized as the analog (II) of I, chacotriose being replaced by gracillimtriose, corresponding to gracillin (IV). One of the minor components was identified with the 22-hydroxy compound (II') of II, mp 235-238°(decomp.), [α]D-57.8°. II'and II are named proto-gracillin and methyl proto-gracillin, respectively. Kikuba-saponin, which had been assigned the structure, IV monoglucoside, was identical with II and the structure is revised.