Noroleanane saponins from Celmisia petriei

Two biologically active noroleanane saponins from Celmisia petriei are identified as 3-O-(α-l-arabinopyranosyl (1 → 6)-β-d-glucopyranosyl (1 → 2)-α-l-arabinopyranosyl), 2β,17,23-trihydroxy-28-norolean-12-en-16-one and its 2″-O-acetyl derivative. ¹³C NMR and T₁ measurements allowed the determination of the sugar sequence and the majority of the linkage positions, but gave ambiguous results for the inner arabinose sugar. The structure of camellenodiol is revised to 3β,17-dihydroxy-28-norolean-12-en-16-one.     

Triterpenoids from the female and male flowers of Alnus sieboldiana

The major triterpenoids in both the female and male flowers of Alnus sieboldiana are a C₃₁-secodammarane-type, alnustic acid, and its 12-O-α-L-arbinofuranoside and 12-O-β-D-xylopyranoside.     

Facile Preparation of Deuterium-Labeled Standards of Indole-3-Acetic Acid (IAA) and Its Metabolites to Quantitatively Analyze the Disposition of Exogenous IAA in Arabidopsis thaliana

[2′,2′-²H₂]-indole-3-acetic acid ([2′,2′-²H₂]IAA) was prepared in an easy and efficient manner involving base-catalyzed hydrogen/deuterium exchange. 1-O-([2′,2′-²H₂]-indole-3-acetyl)-β-D-glucopyranose, [2′,2′-²H₂]-2-oxoindole-3-acetic acid, and 1-O-([2′,2′-²H₂]-2-oxoindole-3-acetyl)-β-D-glucopyranose were also successfully synthesized from deuterated IAA, and effectively utilized as internal standards in the quantitative analysis of IAA and its metabolites in Arabidopsis thaliana by using liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS). The use of this technique shows that these metabolites were accumulated in the roots of Arabidopsis seedlings. Dynamic changes in the metabolites of IAA were observed in response to exogenous IAA, revealing that each metabolic action was regulated differently to contribute to the IAA homeostasis in Arabidopsis.     

Triterpene saponins of Genista ulicina Spach

From the n-BuOH extract of the aerial parts of Genista ulicina, six triterpene saponins, 3-O-β-d-glucopyranosyl-olean-12-ene-3β,27,28,30-tetraol, 3-O-β-d-glucopyranosyl-olean-12-ene-3β,27,28,29-tetraol, 3,29-di-O-β-d-glucopyranosyl-olean-12-ene-3β,27,28,29-tetraol, 3-O-β-d-glucopyranosyl-olean-12-ene-3β,28,29-triol-27-oic acid, 3-O-β-d-glucopyranosyl-olean-12-ene-3β,27,28-triol-29-oic acid, and 3-O-β-d-glucopyranosyl-14-H-27-nor-olean-12-ene-3β,28,29-triol, were isolated together with eight known triterpene saponins and six flavonoids. Their structures were established mainly by means of spectroscopic methods (1D and 2D-NMR as well as HR-ESI-MS). The n-BuOH extract, investigated for its antitumor growth inhibition of human colon cancer HT-29 cells, presented no significant activity (IC₅₀ > 100 μg).     

Ent-kaurene diterpenoids and lignan from Leontopodium leontopodioides and their inhibitory activities against cyclooxygenases-1 and 2

Two new ent-kaurene diterpenoids, 13α,15α-dihydroxy-18-carboxy-19-nor-ent-kaur-16-ene-2β-O-(2′-angelate)-β-d-glucopyranoside (leontocin A, 1), 13α,15α-dihydroxy-18-carboxy-19-nor-ent-kaur-16-ene-2β-O-(2′-angelate-6′-acetyl)-β-d-glucopyranoside (leontocin B, 2), and one new lignan, 2,3-bis[(3,4-di-hydroxyphenyl)methylene]-monoethyl ester-butanedioic acid (leontolignan A, 3), together with three known phenolic acids (4-6) were isolated from the aerial parts of Leontopodium leontopodioides (Asteraceae). Their structures were elucidated by chemical and spectroscopic methods. All isolates were evaluated for their anti-inflammatory activities by measuring their inhibitory effects against cyclooxygenase-1 and 2 in vitro.     

Triterpenoid saponins from Fatsia japonica

Five triterpenoid saponins isolated from the flowers, the mature fruits and the leaves of Fatsia japonica were identified as 3-O-[β-d-glucopyranosyl(1→4)-β-d-glucopyranosyl]-hederagenin (1), 3-O-[β-d-glucopyranosyl-(1→4)-α-l-arabinopyranosyl]-oleanolic acid (2), 3-O-[α-l-arabinopyranosyl]-hederagenin (3), 3-O-[β-d-glucopyranosyl]-hederagenin (4) and 3-O-[β-d-glucopyranosyl(1→4)-α-l-arabinopyranosyl]-hederagenin (5). The saponins 1 and 2 are new, naturally occurring, triterpenoid saponins. The distribution of the five saponins in three parts of the plant was investigated. Saponins 2, 3 and 5 were present in the flowers, saponins 1, 3, 4 and 5 were in the mature fruits and saponins 2, 3, 4 and 5 were in the leaves.     

New triterpene saponins from Phryna ortegioides

Four new and three known oleanane-type saponins have been isolated from the methanolic extract of Phryna ortegioides, a monotypic and endemic taxon of Caryophyllaceae.The structures of the new compounds were determined as gypsogenic acid 28-O-β-d-glucopyranosyl-(1→2)-O-β-d-glucopyranosyl-(1→6)-O-β-d-glucopyranosyl ester (1), 3-O-α-l-arabinofuranosyl-gypsogenic acid 28-O-β-d-glucopyranosyl-(1→3)-O-[β-d-glucopyranosyl-(1→6)]-O-β-d-glucopyranosyl ester (2), 3-O-α-l-arabinofuranosyl-gypsogenic acid 28-O-β-d-glucopyranosyl-(1→3)-O-[β-d-glucopyranosyl-(1→2)-O-β-d-glucopyranosyl-(1→6)-O-]-β-d-glucopyranosyl ester (3), 3-O-α-l-arabinofuranosyl-16α-hydroxyolean-12-en-23,28-dioic acid-28-O-β-d-glucopyranosyl-(1→3)-O-[β-d-glucopyranosyl-(1→2)-O-β-d-glucopyranosyl-(1→6)]-O-β-d-glucopyranosyl ester (4). Their structures were established by a combination of one- and two-dimensional NMR techniques, and mass spectrometry. Noteworthy, none of isolated compounds possesses as aglycone moiety gypsogenin, considered a marker of Caryophyllaceae family.The cytotoxic activity of the isolated compounds was evaluated against three cancer cell lines including A549 (human lung adenocarcinoma), A375 (human melanoma) and DeFew (human B lymphoma) cells. Only compound 6 showed a weak activity against A375 and DeFew cell lines with IC₅₀ values of 77 and 52 μM, respectively. None of the other tested compounds, in a range of concentrations between 12.5 and 100 μM, caused a significant reduction of the cell number.     

Structures of 3,28-O-bisglycosidic triterpenoid saponins of Fatsia japonica

Four novel 3,28-O-bisglycosidic triterpenoid saponins were isolated from the mature fruits of F. japonica. They were characterized as the 28-O-α-l-rhamnopyranosyl-(1 → 4)-β-d-glucopyranosyl-(1 → 4)-β- d-glucopyranosides of 3-O-α-l-arabinopyranosyl echinocystic acid, 3-O-α-l-arabinopyranosyl hederagenin, 3-O-β-d-glucopyranosyl-(1 → 2)-α-l-arabinopyranosyl oleanolic acid and 3-O-β- d-glucopyranosyl-(1 → 2)-α-l-arabinopyranosyl hederagenin respectively.     

Molluscicidal saponins from Gundelia tournefortii

From the roots of Gundelia tournefortii seven saponins have been isolated mainly by DCCC. The main saponins (A and B) were characterized, mainly by ¹³C and ¹H NMR spectroscopy, as oleanolic acid 3-O-(2-[α-l-arabinopyranosyl(1 → 3) -β-d-gentiotriosyl(1 → 6) -β-d-glucopyranosyl]gb-d-xylopyranoside) (saponin A) and oleanolic acid 3-O-(2-[α-l-arabinopyranosyl] (1 → 3)-β-d-gentiobiosyl (1 → 6)-β-d-glucopyranosyl β-d-xylopyranoside) (saponin B). The other saponins are also derived from oleanolic acid and contain more sugar units. The saponin mixture and the saponins A and B possess strong molluscicidal activity against the schistosomiasis transmitting snail Biomphalaria glabrata.     

Astrasieversianins IX,XI and XV,cycloartane derived saponins from Astragalus sieversianus

Sixteen triterpenoid saponins, astrasieversianins I–XVI, have been isolated from the methanol extract of the roots of Astragalus sieversianus. By heterogeneous acidic hydrolysis, all glycosides produced only one common aglycone which was identified as the known natural product astramembrangenin or cycloastragenol. On the basis of spectral analysis and chemical reactions, the structures of two new triterpenoid glycosides, astrasieversianin IX and XI, were assigned as the 3-0-[α-l-rhamnopyranosyl(1 → 2)]-(3'-O-acetyl)-β-d-xylopyranosyl-6-O-β-d-xylopyranoside and the 3-O-[α-l-rhamnopyranosyl(1 → 2)]-(4'-O-acetyl)-β-d-xylopyranosyl-6-β-d-xylopyranoside of cycloastragenol. Astrasieversianin XV was identified as the 20,24-epimer (20R,24S) of cyclosieversiside G (20S,24R).     

Triterpenoid saponins from Sesbania vesicaria

Nine oleanane saponins including three new and six known were isolated from the seeds of Sesbania vesicaria. The new saponins were established as 3-O-[α-l-rhamnopyranosyl-(1 → 3)]-β-d-glucuronopyranosyl-3β,29-dihydroxy-olean-12-en-28-oic acid, 3-O-α-l-rhamnopyranosyl-28-O-β-d-glucopyransoyl-3β-hydroxy-olean-12-en-23-al-28-oate, and 3-O-α-l-rhamnopyranosyl-28-O-β-d-glucopyransoyl-3β,23-dihydroxy-olean-12-en-28-oate. All isolated saponins were assayed for their DNA topoisomerase I inhibition ability and cytotoxicity against A549 human lung adenocarcinoma epithelial cells with no positive activity detected (IC₅₀ > 312 μM and GI₅₀ > 25 μM, respectively).     

Obtusilobinin and obtusilobin,two new triterpene saponins from Anemone obtusiloba

Obtusilobinin and obtusilobin, two new saponins, have been isolated from the ethanolic extract of Anemone obtusiloba (Ranunculaceae). The structural elucidation of obtusilobinin and obtusilobin have showed them to be olean-12-ene-28-oic-3-O-(α-l-arabinofuranosyl 1→2) (α-l-rhamnopyranosyl 1→4)-β-d-glucopyranoside and olean-12-ene-28-oic-3-O-α-l-rhamnopyranosyl 2→1-O-α-l-arabinofuranoside, respectively.     

Triterpenoid saponins from the flower buds of Fatsia japonica

Six triterpenoid saponins isolated from the flower buds of Fatsia japonica were identified as 3-O-[β-D-glucopyranosyl(1 → 4)-α-L-arabinopyranosyl]-oleanolic acid, 3-O-[α-L-arabinopyranosyl]-hederagenin, 3-O-[β-D-glucopyranosyl(1 → 4)-α-L-arabinopyranosyl]-hederagenin, 3-O-[α-L-arabinopyranosyl]-echinocystic acid, 3-O-[α-L-arabinopyranosyl]-16-epiechinocystic acid and 3-O-[α-L-arabinopyranosyl]-oleanolic acid. Of these saponins, three are new.     

Biotransformation of o- and p-aminobenzoic acids and N-acetyl p-aminobenzoic acid by cell suspension cultures of Solanum mammosum

Some new biotransformation products, p-aminobenzoic acid 7-O-β-d-glucopyranosyl ester, N-acetyl p-aminobenzoic acid 7-O-β-d-glucopyranosyl ester, o-aminobenzoic acid 7-O-β-d-(β-1,6-O-d-glucopyranosyl)glucopyranosyl ester and o-aminobenzoic acid 7-O-β-d-glucopyranosyl ester were isolated from cell suspension cultures of Solanum mammosum following administration of p-aminobenzoic acid, N-acetyl p-aminobenzoic acid or o-aminobenzoic acid respectively. N-acetyl p-aminobenzoic acid and N-formyl p-aminobenzoic acid were also identified as cell suspension metabolites of p-aminobenzoic acid.     

Identification of 2-O (indole-3-acetyl)-D-glucopyranose, 4-O-(indole-3-acetyl)-D-glucopyranose and 6-O-(indole-3-acetyl)-D-glucopyranose from kernels of Zea mays by gas-liquid chromatography-mass spectrometry

New esters of indole-3-acetic acid and d-glucose have been isolated from mature sweet-corn kernels of Zea mays. The esters were resolved by t.l.c. into two fractions having R_F values distinct from that of authentic 1-O-(indole-3-acetyl)-β-d-glucopyranose. Analysis of the trimethylsilyl ethers of the two fractions by combined gas-liquid chromatography-mass spectrometry (g.l.c.-m.s.) showed that the esters have a free carbonyl group. Labeling of the carbonyl carbon atom with an O-methyloxime group, and analysis of the O-trimethylsilyl O-methyloxime derivatives by g.l.c.-m.s. permitted the new compounds to be identified as a mixture of 2-O-(indole-3-acetyl)-d-glucopyranose, 4-O-(indole-3-acetyl)-d-glucopyranose, and 6-O-(indole-3-acetyl)-d-glucopyranose.     

Pendulaosides A and B. Two acylated triterpenoid saponins from Harpullia pendula seed extract

Two new acylated triterpenoid saponins named pendulaosides A and B as well as the known phenolic compounds methyl gallate, gallic acid, 1,2,3,6-tera-O-galloyl-β-d-glucose and 1,2,3,4,6-penta-O-galloyl-β-d-glucose, were isolated from the seeds of Harpullia pendula. The structures of pendulaosides A and B were determined using extensive 1D and 2D NMR analysis and mass spectrometry as well as acid hydrolysis, as 3-O-β-d-glucopyranosyl-(1→2)-[α-L-arabinofuranosyl-(1→3)]-β-d-glucuronopyranosyl-22-O-angeloyl-3β,16α,22α,24β,28-pentahydroxylolean-12-ene and 3-O-β-d-glucopyranosyl-(1→2)-[α-L-arabinofuranosyl-(1→3)]-β-d-glucuronopyranosyl-16-O-(2-methylbutyroyl)-3β,16α,22α,24β,28-pentahydroxylolean-12-ene, respectively. To the best of our knowledge the two triterpene parts 22-O-angeloyl-3β,16α,22α,24β,28-pentahydroxylolean-12-ene and16-O-(2-methylbutyroyl)-3β,16α,22α,24β,28-pentahydroxylolean-12-ene have never been characterized before. The two isolated saponins were assayed for their in-vitro cytotoxic activity against the three human tumor cell lines HepG2, MCF7 and PC3. The results showed that pendulaoside A exhibited moderate activity on PC3 cell line with IC50value equal to 13.0 μM and weak activity on HepG2 cell line with IC50 value equal to 41.0 μM. Pendulaoside B proved to be inactive against the three used cell lines.     

Two acylated flavanone glycosides from Nierembergia hippomanica

Two new acylated flavanone glycosides have been isolated from Nierembergia hippomanica and identified by spectral data as pinocembrin 7-O-β-(3?-O-acetyl)neohesperidoside and pinocembrin 7-O-β-(6″-O-acetyl)neohesperidoside.     

Unusual oleanane-type saponins from Arenaria montana

Three oleanane-type saponins, 3-O-β-d-glucopyranosylechinocystic acid 28-O-β-d-xylopyranosyl-(1→4)-[α-l-rhamnopyranosyl-(1→2)]-α-l-rhamnopyranosyl ester (1), 3-O-β-d-glucopyranosylechinocystic acid 28-O-α-l-arabinopyranosyl-(1→3)-β-d-xylopyranosyl-(1→4)-[α-l-rhamnopyranosyl-(1→2)]-α-l-rhamnopyranosyl ester (2), 3-O-β-d-glucopyranosylcaulophyllogenin 28-O-β-d-apiofuranosyl-(1→3)-β-d-xylopyranosyl-(1→4)-[β-d-apiofuranosyl-(1→3)]-α-l-rhamnopyranosyl-(1→2)-α-l-rhamnopyranosyl ester (3) were isolated from the whole plant of Arenaria montana. Their unusual structures for the Caryophyllaceae family were established mainly by 2D NMR techniques and mass spectrometry.     

Structures of verbascoside and orobanchoside,caffeic acid sugar esters from Orobanche rapum-genistae

The complete structural elucidation of the two caffeic acid sugar esters verbascoside and orobanchoside, has been realized by ¹H and ¹³C NMR studies. It has been demonstrated that verbascoside is β-(3′,4′-dihydroxyphenyl)ethyl-O-α-L-rhamnopyranosyl(1→3)-β-D-(4-O-caffeoyl)-glucopyranoside, and orobanchoside is β-hydroxy-β-(3′,4′-dihydroxyphenyl)-ethyl-O-α-L-rhamnopyranosyl(1→2)-β-D-(4-O-caffeoyl)-glucopyranoside.     

Cyanogenic glycosides in leaves of Perilla frutescens var. acuta

Besides 7-(2-O-β-D-glucuronyl-β-D-glucuronyloxy)-5,3′,4′-trihydroxyflavone, scutellarin, rosmarinic acid and caffeic acid, two cyanogenic glycosides have been isolated from the dried leaves of Perilla frutescens var. acuta. One of them is prunasin and the other is (R)-2-(2-O-β-D-glucopyranosyl-β-D-glucopyranosyloxy)-phenylacetonitrile, a new isomer of amygdalin.