Flavonoids from the flowers of Adenium obesum (Forssk.) Roem. & Schult., Mandevilla sanderi (Hemsl.) Woodson,and Nerium oleander L. (Apocynaceae)

Twenty-two ornamental flowers from different Adenium obesum, Mandevilla sanderi, and Nerium oleander cultivars/seedlings were analyzed for the presence of anthocyanins, flavonols, and chlorogenic acid using nuclear magnetic resonance (NMR) and mass spectrometry (MS). Cyanidin 3-O-[6-O-(rhamnosyl)-galactoside] and cyanidin 3-O-(galactoside) were identified as the major and minor anthocyanins, respectively, in three A. obesum seedlings that had red and red-purple flowers.Cyanidin 3-O-[2-O-(xylosyl)-galactoside] was identified as the major anthocyanin, whereas cyanidin 3-O-[6-O-(rhamnosyl)-galactoside] and cyanidin 3-O-(galactoside) were identified as the minor anthocyanins in 8 M. sanderi cultivars that had red and red-purple flowers. Cyanidin 3-O-[6-O-(rhamnosyl)-galactoside] and cyanidin 3-O-(galactoside) were identified as the major anthocyanins, whereas cyanidin 3-O-[2-O-(xylosyl)-galactoside] was identified as the minor anthocyanin in 8 N. oleander cultivars with red and red-purple flowers. Low levels of anthocyanins were detected in the N. oleander and M. sanderi cultivars that had white flowers, and there were no anthocyanins detected in the N. oleander cultivars with yellow flowers. Chlorogenic acid and four flavonols, quercetin 3-O-[6-O-(rhamnosyl)-galactoside], quercetin 3-O-[6-O-(rhamnosyl)-glucoside], kaempferol 3-O-(galactoside), and kaempferol 3-O-[6-O-(rhamnosyl)-galactoside], were identified in the flowers from all 22 cultivars/seedlings investigated.     

Acylated cyanidin 3-sambubioside-5-glucosides from the purple-violet flowers of Matthiola longipetala subsp. bicornis (Sm) P. W. Ball. (Brassicaceae)

A novel acylated cyanidin 3-sambubioside-5-glucoside was isolated from the purple-violet flowers of Matthiola longipetala subsp. bicornis (Sm) P. W. Ball. (family: Brassicaceae), and determined to be cyanidin 3-O-[2-O-(2-O-(trans-feruloyl)-β-xylopyranosyl)-6-O-(trans-feruloyl)-β-glucopyranoside]-5-O-[6-O-(malonyl)-β-glucopyranoside] by chemical and spectroscopic methods. In addition, two known acylated cyanidin 3-sambubioside-5-glucosides, cyanidin 3-O-[2-O-(2-O-(trans-sinapoyl)-β-xylopyranosyl)-6-O-(trans-feruloyl)-β-glucopyranoside]-5-O-[6-O-(malonyl)-β-glucopyranoside] and cyanidin 3-O-[2-O-(β-xylopyranosyl)-6-O-(trans-feruloyl)-β-glucopyranoside]-5-O-[6-O-(malonyl)-β-glucopyranoside] were identified in the flowers.     

Anthocyanins in Caprifoliaceae

The qualitative and relative quantitative anthocyanin content of 19 species belonging to the genera Sambucus, Lonicera and Viburnum in the family Caprifoliaceae has been determined. Altogether 12 anthocyanins were identified; the 3-O-glucoside (2), 3-O-galactoside (5), 3-O-(6″-O-arabinosylglucoside) (7), 3-O-(6″-O-rhamnosylglucoside) (9), 3-O-(2″-O-xylosyl-6″-O-rhamnosylglucoside) (10), 3-O-(2″-O-xylosylgalactoside) (11), 3-O-(2″-O-xylosylglucoside) (12), 3-O-(2″-O-xylosylglucoside)-5-O-glucoside (14), 3-O-(2″-O-xylosyl-6″-O-Z-p-coumaroylglucoside)-5-O-glucoside (15) and 3-O-(2″-O-xylosyl-6″-O-E-p-coumaroylglucoside)-5-O-glucoside (16) of cyanidin, in addition to the 3-O-glucosides of pelargonidin and delphinidin (1 and 3). Pigment 7 is the first complete identification of the disaccharide vicianose, 6″-O-α-arabinopyranosyl-β-glucopyranose, linked to an anthocyanidin.     

Anthocyanins from red flowers of Camellia cultivar 'Dalicha'

Five anthocyanins, cyanidin 3-O-(2-O-β-xylopyranosyl-6-O-(Z)-p-coumaroyl)-β-galactopyranoside (2), cyanidin 3-O-(2-O-β-xylopyranosyl-6-O-(E)-p-coumaroyl)-β-galactopyranoside (3), cyanidin 3-O-(2-O-β-xylopyranosyl-6-O-(E)-caffeoyl)-β-galactopyranoside (4), cyanidin 3-O-(2-O-β-xylopyranosyl-6-O-acetyl)-β-galactopyranoside (5), and cyanidin 3-O-(2-O-β-xylopyranosyl-6-O-acetyl)-β-glucopyranoside (6), together with the known cyanidin 3-O-(2-O-β-xylopyranosyl)-β-galactopyranoside (1), were isolated from red flowers of Camellia cultivar ‘Dalicha’ (Camellia reticulata) by chromatography using open columns. Their structures were subsequently determined on the basis of spectroscopic analyses, i.e., ¹H NMR, ¹³C NMR, HMQC, HMBC, HR ESI-MS and UV-vis.     

Covalent anthocyanin–flavonol complexes from the violet-blue flowers of Allium ‘Blue Perfume’

Three covalent anthocyanin–flavonol complexes (pigments 1–3) were extracted from the violet-blue flower of Allium ‘Blue Perfume’ with 5% acetic acid-MeOH solution, in which pigment 1 was the dominant pigment. These three pigments are based on delphinidin 3-glucoside as their deacylanthocyanin and were acylated with malonyl kaempferol 3-sophoroside-7-glucosiduronic acid or malonyl-kaempferol 3-p-coumaroyl-tetraglycoside-7-glucosiduronic acid in addition to acylation with acetic acid.By spectroscopic and chemical methods, the structures of these three pigments 1–3 were determined to be: pigment 1, (6^I-O-(delphinidin 3-O-(3^I-O-(acetyl)-β-glucopyranoside^I)))(2^VI-O-(kaempferol 3-O-(2^II-O-(3^III-O-(β-glucopyranosyl^V)-β-glucopyranosyl^III)-4^II-O-(trans-p-coumaroyl)-6^II-O-(β-glucopyranosyl^IV)-β-glucopyranoside^II)-7-O-(β-glucosiduronic acid^VI))) malonate; pigment 2, (6^I-O-(delphinidin 3-O-(3^I-O-(acetyl)-β-glucopyranoside^I)))(2^VI-O-(kaempferol 3-O-(2^II-O-β-glucopyranosyl^III)-β-glucopyranoside^II)-7-O-(β-glucosiduronic acid^VI))); and pigment 3, (6^I-O-(delphinidin 3-O-(3^I-O-(acetyl)-β-glucopyranoside^I)))(2^VI-O-(kaempferol 3-O-(2^II-O-(3^III-O-(β-glucopyranosyl^V)-β-glucopyranosyl^III)-4^II-O-(cis-p-coumaroyl)-6^II-O-(β-glucopyranosyl^IV)-β-glucopyranoside^II)-7-O-(β-glucosiduronic acid^VI))) malonate.The structure of pigment 2 was analogous to that of a covalent anthocyanin–flavonol complex isolated from Allium schoenoprasum where delphinidin was observed in place of cyanidin. The three covalent anthocyanin–flavonol complexes (pigment 1–3) had a stable violet-blue color with three characteristic absorption maxima at 540, 547 and 618 nm in pH 5–6 buffer solution. From circular dichroism measurement of pigment 1 in the pH 6.0 buffer solution, cotton effects were observed at 533 (+), 604 (−) and 638 (−) nm. Based on these results, these covalent anthocyanin–flavonol complexes were presumed to maintain a stable intramolecular association between delphinidin and kaempferol units closely related to that observed between anthocyanin and hydroxycinnamic acid residues in polyacylated anthocyanins. Additionally, an acylated kaempferol glycoside (pigment 4) was isolated from the same flower extract, and its structure was determined to be kaempferol 3-O-sophoroside-7-O-(3-O-(malonyl)-β-glucopyranosiduronic acid).     

N-Substituted acetamide glycosides from the stems of Ephedra sinica

Five new N-mono-/bis-substituted acetamide glycosides, N-{4-O-[3-O-(4-O-α-l-rhamnopyranosyl-β-d-glucopyranosyl)-α-l-rhamnopyranosyl]-phenethyl}-acetamide (1), N-methyl-N-{4-O-[3-O-(4-O-α-l-rhamnopyranosyl-β-d-glucopyranosyl)-α-l-rhamnopyranosyl]-phenethyl}-acetamide (2), N-methyl-N-{4-O-[3-O-(6-O-benzoyl-4-O-α-l-rhamnopyranosyl-β-d-glucopyranosyl)-α-l-rhamnopyranosyl]-phenethyl}-acetamide (3), N-methyl-N-{4-O-[3-O-(6-O-benzoyl-β-d-glucopyranosyl)-α-l-rhamnopyranosyl]-phenethyl}-acetamide (4), and N-methyl-N-{4-O-[3-O-(6-O-trans-cinnamoyl-4-O-α-l-rhamnopyranosyl-β-d-glucopyranosyl)-α-l-rhamnopyranosyl]-phenethyl}-acetamide (5), along with one known acetamide derivative, N-methyl-N-(4-hydroxyphenethyl)-acetamide, the shared aglycone of 2–5, were isolated from the ethanol extract of the stems of Ephedra sinica. The structures of these new compounds were elucidated on the basis of extensive spectroscopic examination, mainly including multiple 1D and 2D NMR and HRESIMS examinations, and qualitative chemical tests. All N,N-bissubstituted acetamide glycosides were found to show the obvious rotamerism, as in the case of the isolated known N-methyl-N-(4-hydroxyphenethyl)-acetamide, under the experimental NMR conditions, with the ratios of integrated intensities between anti- and syn-rotamers always being found to be about 4 to 3.     

Glycosides from Breynia fruticosa and Breynia rostrata

Glycosides, 3-acetyl-(?)-epicatechin 7-O-β-glucopyranoside (1), 3-acetyl-(?)-epicatechin 7-O-(6-isobutanoyloxyl)-β-glucopyranoside (2), 3-acetyl-(?)-epicatechin 7-O-[6-(2-methyl-butanoyloxyl)]-β-glucopyranoside (3), (5Z)-6-[5-(2-hydroxypropan-2-yl)-2-methyl-tetrahydrofuran-2-yl]-3-methylhexa-1,5-dien-3-O-β-glucopyranoside (4), hydroquinone O-[6-(3-hydroxyisobutanoyl)]-β-galactopyranoside (5), 4-(4-O-β-glucopyranosyl-phenoxy)-1-O-β-glucopyranosyl-1,3-benzenediol (6), 7,8-erythro-dihydroxy-3,4,5-trimethoxy-phenyl-propane8-O-β-glucopyranoside (7), 6,7-dimethylbenzofuranol 5-O-β-xylopyranosyl-(1 → 6)-β-glucopyranoside (8), along with 30 known glycosides, were isolated from Breynia fruticosa and Breynia rostrata (Euphorbiaceae). Their structures were determined on the basis of spectroscopic analysis and chemical methods.     

Tetra-acylated cyanidin 3-sophoroside-5-glucosides from the flowers of Iberis umbellata L. (Cruciferae)

The structures of 11 acylated cyanidin 3-sophoroside-5-glucosides (pigments 1-11), isolated from the flowers of Iberis umbellata cultivars (Cruciferae), were elucidated by chemical and spectroscopic methods. Pigments 1-11 were acylated with malonic acid, p-coumaric acid, ferulic acid, sinapic acid and/or glucosylhydroxycinnamic acids.Pigments 1-11 were classified into four groups by the substitution patterns of the linear acylated residues at the 3-position of the cyanidin. In the first group, pigments 1-3 were determined to be cyanidin 3-O-[2-O-(2-O-(acyl)-β-glucopyranosyl)-6-O-(trans-p-coumaroyl)-β-glucopyranoside]-5-O-[6-O-(malonyl)-β-glucopyranoside], in which the acyl moiety varied with none for pigment 1, ferulic acid for pigment 2 and sinapic acid for pigment 3. In the second one, pigments 4-6 were cyanidin 3-O-[2-O-(2-O-(acyl)-β-glucopyranosyl)-6-O-(4-O-(β-glucopyranosyl)-trans-p-coumaroyl)-β-glucopyranoside]-5-O-[6-O-(malonyl)-β-glucopyranoside], in which the acyl moiety varied with none for pigment 4, ferulic acid for pigment 5 and sinapic acid for pigment 6. In the third one, pigments 7-9 were cyanidin 3-O-[2-O-(2-O-(acyl)-β-glucopyranosyl)-6-O-(4-O-(6-O-(trans-feruloyl)-β-glucopyranosyl)-trans-p-coumaroyl)-β-glucopyranoside]-5-O-[6-O-(malonyl)-β-glucopyranoside], in which the acyl moiety varied with none for pigment 7, ferulic acid for pigment 8, and sinapic acid for pigment 9. In the last one, pigments 10 and 11 were cyanidin 3-O-[2-O-(2-O-(acyl)-β-glucopyranosyl)-6-O-(4-O-(6-O-(4-O-(β-glucopyranosyl)-trans-feruloyl)-β-glucopyranosyl)-trans-p-coumaroyl)-β-glucopyranoside]-5-O-[6-O-(malonyl)-β-glucopyranoside], in which acyl moieties were none for pigment 10 and ferulic acid for pigment 11.The distribution of these pigments was examined in the flowers of four cultivars of I. umbellata by HPLC analysis. Pigment 1 acylated with one molecule of p-coumaric acid was dominantly observed in purple-violet cultivars. On the other hand, pigments (9 and 11) acylated with three molecules of hydroxycinnamic acids were observed in lilac (purple-violet) cultivars as major anthocyanins. The bluing effect and stability on these anthocyanin colors were discussed in relation to the molecular number of hydroxycinnamic acids in these anthocyanin molecules.     

Cycloartane-type glycosides from Astragalus amblolepis

Five cycloartane-type triterpene glycosides were isolated from the methanol extract of the roots of Astragalus amblolepis Fischer along with one known saponin, 3-O-β-D-xylopyranosyl-16-O-β-D-glucopyranosyl-3β,6α,16β,24(S),25-pentahydroxy-cycloartane. Structures of the compounds were established as 3-O-β-D-xylopyranosyl-25-O-β-D-glucopyranosyl-3β,6α,16β,24(S),25-pentahydroxy-cycloartane, 3-O-[β-D-glucuronopyranosyl-(1 → 2)-β-D-xylopyranosyl]-25-O-β-D-glucopyranosyl-3β,6α,16β,24(S),25-pentahydroxy-cycloartane, 3-O-β-D-xylopyranosyl-24,25-di-O-β-D-glucopyranosyl-3β,6α,16β,24(S),25-pentahydroxy-cycloartane, 6-O-α-L-rhamnopyranosyl-16,24-di-O-β-D-glucopyranosyl-3β,6α,16β,24(S),25-pentahydroxy-cycloartane, 6-O-α-L-rhamnopyranosyl-16,25-di-O-β-D-glucopyranosyl-3β,6α,16β,24(S),25-pentahydroxy-cycloartane by using 1D and 2D-NMR techniques and mass spectrometry. To the best of our knowledge, the glucuronic acid moiety in cycloartanes is reported for the first time.     

Unique flavonoid glycosides from the new zealand white pine, Dacrycarpus dacrydioides

A number of new flavonoid glycosides have been isolated from foliage of the New Zealand white pine, Dacrycarpus dacrydioides. These include tricetin 3′,5′-di-O-β-glucopyranoside; the 3′-O-β-xylopyranoside, 7-O-α-rhamnopyranoside and 7-O-α-rhamnopyranoside-3′-O-β-xylopyranoside of 3-O-methylmyricetin; the 3′-O-β-xylopyranoside, 7-O-α-rhamnopyranoside and 7-O-α-rhamnopyranoside-3′-O-β-xylopyranoside of 3-O-methyl-quercetin, and the 3′-O-β-xylopyranoside and 7-O-α-rhamnopyranoside-3′-O-β-xylopyranoside of 3,4′-di-O-methylmyricetin. The accumulation of 3-methoxyflavones and B-ring trioxygenated flavonoids appears to distinguish D. dacrydioides from all other New Zealand members of the classical genus Podocarpus. Support for De Laubenfels' proposed separation of Dacrycarpus from this genus is seen in the present work.     

Triterpene glycosides from Astragalus icmadophilus

Six cycloartane-type triterpene glycosides were isolated from Astragalus icmadophilus along with two known cycloartane-type glycosides, five known oleanane-type triterpene glycosides and one known flavonol glycoside. The structures of the six compounds were established as 3-O-[α-L-arabinopyranosyl-(1 → 2)-O-3-acetoxy-α-L-arabinopyranosyl]-6-O-β-D-glucopyranosyl-3β,6α,16β,24(S),25-pentahydroxycycloartane, 3-O-[α-L-rhamnopyranosyl-(1 → 2)-O-α-L-arabinopyranosyl-(1 → 2)-O-β-D-xylopyranosyl]-6-O-β-D-glucopyranosyl-3β,6α,16β,24(S),25-pentahydroxy cycloartane, 3-O-[α-L-arabinopyranosyl-(1 → 2)-O-3,4-diacetoxy-α-L-arabinopyranosyl]-6-O-β-D-glucopyranosyl-3β,6α,16β,24(S),25-pentahydroxycycloartane, 3-O-[α-L-arabinopyranosyl-(1 → 2)-O-3-acetoxy-α-L-arabinopyranosyl]-6-O-β-D-glucopyranosyl-3β,6α,16β,25-tetrahydroxy-20(R),24(S)-epoxycycloartane, 3-O-[α-L-arabinopyranosyl-(1 → 2)-O-β-D-xylopyranosyl]-6-O-β-D-glucopyranosyl-3β,6α,16β,24α-tetrahydroxy-20(R),25-epoxycycloartane, 3-O-[α-L-rhamnopyranosyl-(1 → 2)-O-α-L-arabinopyranosyl-(1 → 2)-O-β-D-xylopyranosyl]-6-O-β-D-glucopyranosyl-3β,6α,16β,24α-tetrahydroxy-20(R),25-epoxycycloartane by the extensive use of 1D- and 2D-NMR experiments along with ESIMS and HRMS analysis.The first four compounds are cyclocanthogenin and cycloastragenol glycosides, whereas the last two are based on cyclocephalogenin as aglycone, more unusual in the plant kingdom, so far reported only from Astragalus spp.     

Cycloartane triterpenoids from the aerial parts of Cimicifuga foetida Linnaeus

Cycloartane triterpenoids, 2′,24-O-diacetylisodahurinol-3-O-α-l-arabinopyranoside, 24-O-acetylisodahurinol-3-O-α-l-arabinopyranoside, 12β-hydroxy-25-anhydrocimigenol, cimigenol-12-one, 12β-hydroxy-15-deoxycimigenol, 2′-O-acetyl-24-epi-cimigenol-3-O-α-l-arabinopyranoside, 2′-O-acetylcimigenol-3-O-β-d-xylopyranoside, 25-anhydrocimigenol-3-O-α-l-arabinopyranoside, 2′,23-O-diacetylshengmanol-3-O-α-l-arabinopyranoside, and 2′,24-O-diacetyl-25-anhydrohydroshengmanol-3-O-α-l-arabinopyranoside, together with eight known compounds, were isolated from aerial parts of Cimicifuga foetida. Their structures were determined by application of spectroscopic analyses and chemical methods. Biological evaluation of the compounds against human HL-60, SMMC-7721, A549, SK-BR-3, and PANC-1 cell lines indicated that three of these compounds exhibited broad-spectrum and moderate cytotoxic activities, with IC₅₀ values ranging from 6.20 to 22.74 μM. By comparing previous cytotoxic testing data and bioassay results from this study, preliminary structure–activity relationships of compounds with a cimigenol-skeleton can be proposed.     

Synthesis of nonreducing-sugar subunit analogs of bacterial lipid a carrying an amide-group (3R)-3-acyloxytetradecanoyl group

Two types of optically active, 4-O-phosphono-d-glucosamine derivatives related to the nonreducing-sugar subunit of bacterial lipid A, one being 2-[(3R)-3-acyloxytetradecanamido]-2-deoxy-4-O-phosphono-3-O-tetradecanoyl-d-glucose (GLA-27 type; GLA-57 and GLA-58), and the other 2-[(3R)-3-acyloxytetradecanamido]-2-deoxy-3-O-[(3R)-3-hydroxytetradecanoyl]-4-O-phosphono-d-glucose (GLA-59 type; GLA-61 and GLA-62), have been synthesized. The amino group of benzyl 2-amino-2-deoxy-4,6-O-isopropylidene-β-d-glucopyranoside was first acylated with the (3R)-3-dodecanoyloxytetradecanoyl or (3R)-3-hexadecanoyloxytetradecanoyl group, and then the remaining hydroxyl group was esterified with the tetradecanoyl or (3R)-3-(benzyloxymethoxy)tetradecanoyl group, respectively. The resulting protected intermediates were each converted, by the sequence of O-deisopropylidenation, 6-O-trityltion, and 4-O-phosphorylation, into the desired compounds.     

Synthesis and 13C-N.M.R. spectroscopy of 2-O- and 6-O-acetyl-3-O-α-l-rhamnopyranosyl-d-galactose,constituents of bacterial cell-wall polysaccharides

Benzyl 2-O-acetyl-4,6-O-benzylidene-3-O-(2,3,4-tri-O-acetyl-α-l-rhamnopyranosyl)-β-d-galactopyranoside (11) has been synthesised by two routes. Partial deacetylation of 11 and then acid hydrolysis yielded benzyl 2-O-acetyl-3-O-α-l-rhamnopyranosyl-β-d-galactopyranoside, catalytic hydrogenolysis of which gave the first title compound in excellent yield. Benzyl 4,6-O-benzylidene-3-O-α-l-rhamnopyranosyl-β-d-galactopyranoside was benzylated, and hydrogenolysis (LiAlH₄-AlCl₃) of the product gave the disaccharide derivative 16 with only HO-6 unsubstituted. Acetylation of 16 followed by catalytic hydrogenolysis gave the crystalline, second title compound. As model compounds for comparative n.m.r. studies, 2-O-, 3-O-, and 6-O-acetyl-d-galactose were also synthesised.     

Sulphated polysaccharides of the grateloupiaceae family : Part VII. Investigation of the acetolysis products of a partially desulphated sample of the polysaccharide of pachymenia carnosa

Investigation of the acetolysis products of a partially desulphated sample of the polysaccharide isolated from Pachymenia carnosa led to the isolation and characterization of the following oligosaccharides: 3-O-α-D-galactopyranosyl-D-galactose (1), 4-O-β-D-galactopyranosyl-D-galactose (2), 3-O-(2-O-methyl-α-D-galactopyranosyl)-D-galactose (3), a 4-O-galactopyranosyl-2-O-methylgalactose (4), 3-O-α-D-galactopyranosyl-6-O-methyl-D-galactose (5), 4-O-β-D-galactopyranosyl-2-O-methyl-D-galactose (6), 2-O-methyl-4-O-(6-O-methyl-β-D-galactopyranosyl)-D-galactose (14), O-β-D-galactopyranosyl-(1→4)-O-α-D-galactopyranosyl-(1→3)-D-galactose (8), O-α-D-galactopyranosyl-(1→3)-O-β-D-galactopyranosyl-(1→4)-D-galactose (9), O-β-D-galactopyranosyl-(1→4)-O-α-(2-O-methyl-D-galactopyranosyl)-(1→3)-D-galactose (11), O-α-(2-O-methyl-D-galactopyranosyl)-(1→3)-O-β-D-galactopyranosyl-(1→4)-D-galactose (12), O-α-D-galactopyranosyl-(1→3)-O-β-D-galactopyranosyl-(1→4)-2-O-methyl-D-galactose (13), O-α-(2-O-methyl-D-galactopyranosyl)-(1→3)-O-β-D-galactopyranosyl-(1→4)-2-O-methyl-D-galactose (16), and O-β-D-galactopyranosyl-(1→4)-O-α-D-galactopyranosyl-(1→3)-O-β-D-galactopyranosyl-(1→4)-D-galactose (10). In addition, evidence was obtained for the presence of 4-O-(6-O-methyl-β-D-galactopyranosyl)-D-galactose (7) and O-β-D-galactopyranosyl-(1→4)-O-α-D-galactopyranosyl-(1→3)-6-O-methyl-D-galactose (15).     

Pyruvic acid-containing mono- and oligo-saccharides from rhizobium trifolii bart A

After partial, acid hydrolysis of the extracellular, acid polysaccharide from Rh. trifolii Bart A, the following products were isolated and characterized: 3,4-O-(1-carboxyethylidene)-d-galactose, 4,6-O-(1-carboxyethylidene)-d-galactose, 3-O-[3,4-O-(1-carboxyethylidene)-β-d)-galactopyranosyl]-d-glucose, 3-O-[4,6-O-(1-carboxyethylidene)-β-d-galactopyranosyl]-d-glucose, O-[3,4-O-(1-carboxyethylidene)-β-d-galactopyranosyl ]-(1→3)-O-d-glucopyranosyl-(1→4)-d-glucose, and O-[4,6-O-(1- carboxyethylidene)-β-d-galactopyranosyl]-(1→3)-O-β-d-glucopyranosyl-(1→4)-d-glucose. The presence of pyruvic acid linked either to O-3 and O-4 or to O-4 and O-6 of the d-galactopyranosyl group of these saccharides indicates that both structures may be present in the original polysaccharide.     

Differences in the floral anthocyanin content of violet–blue flowers of Vinca minor L. and V. major L. (Apocynaceae)

Two novel delphinidin 3-(tri or di)-glycoside-7-glycosides were isolated from the violet–blue flowers of Vinca minor L. and V. major L. (Family: Apocynaceae), and determined to be delphinidin 3-O-[2-O-(β-xylopyranosyl)-6-O-(α-rhamnopyranosyl)-β-galactopyranoside]-7-O-(α-rhamnopyranoside) [= delpphinidin 3-(2^G-xylosylrobinobioside)-7-rhamnoside] as major floral anthocyanin of V. minor and delphinidin 3-O-[6-O-(α-rhamnopyranosyl)-β-galactopyranoside]-7-O-(α-rhamnopyranoside) [= delpphinidin 3-robinobioside-7-rhamnoside] as major floral anthocyanin of V. major by chemical and spectroscopic methods. In addition, chlorogenic acid and kaempferol 3-O-[6-O-(α-rhamnopyranosyl)-β-galactopyranoside]-7-O-(α-rhamnopyranoside) [= kaempferol 3-robinobioside-7-rhamnoside (robinin)] were identified in these flowers. In this paper, the relation between the structure of floral anthocyanins and classification of Vinca species was discussed.     

New trans- and cis-p-coumaroyl flavonol tetraglycosides from the leaves of Mitragyna rotundifolia

Two new flavonol tetraglycosides, quercetin 3-O-(4-O-trans-p-coumaroyl)-α-l-rhamnopyranosyl (1→2) [α-l-rhamnopyranosyl (1→6)]-β-d-glucopyranoside-7-O-α-l-rhamnopyranoside (krathummuoside A) and quercetin 3-O-(4-O-cis-p-coumaroyl)-α-l-rhamnopyranosyl (1→2) [α-l-rhamnopyranosyl (1→6)]-β-d-glucopyranoside-7-O-α-l-rhamnopyranoside (krathummuoside B) were isolated from the leaves of Mitragyna rotundifolia in addition to eight known compounds, quercetin 3-O-α-l-rhamnopuranosyl (1→2) [α-l-rhamnopyranosyl (1→6)]-β-d-glucopyranoside-7-O-α-l-rhamnopyranoside, rutin, (−)-epi-catechin, 3,4,5-trimethoxyphenyl β-d-glucopyranoside, (6S, 9R)-roseoside, 3-O-β-d-glucopyranosyl quinovic acid 28-O-β-d-glucopyranosyl ester, (+)-lyoniresinol 3α-O-β-d-glucopyranoside, and (+)-syringaresinol-4-O-β-d-glucopyranoside. The structure elucidation of these compounds was based on analyses of spectroscopic data including 1D- and 2D-NMR.     

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.     

Synthesis of myo- and muco-inositol esters,and some nitrogen derivatives thereof

Starting from myo-inositol, 1,2-O-isopropylidene-3,4,5,6-tetra-O-(methylsulfonyl)-, 1,4,5,6-tetra-O-(methylsulfonyl)-, and 2,3-di-O-acetyl-1,4,5,6-tetra-O-(methylsulfonyl)-myo-inositol (3) were synthesized. Compound 3 was treated with sodium azide to give 3-azido-3-deoxy-1,5,6-tri-O-(methylsulfonyl)-muco-inositol, reduction of whose diacetate led to a mixture of 3-amino-3-deoxy- and 3-acetamido-2-O-acetyl-3-deoxy-1,5,6-tri-O-(methylsulfonyl)-muco-inositol. The configurations and conformations of these compounds were ascertained by n.m.r. spectroscopy. 3-Acetamido-3-deoxy-1,5,6-tri-O-(methylsulfonyl)-muco-inositol and its 2,4-diacetate are also described.