Triterpene glycosides ofAstragalus and their genins XLV. The chemical transformation of cycloartanes 1. Synthesis of 25-norglycosides

Literature information is given on the current state of the study of the chemical transformation of cycloartane triterpenoids. A method has been developed for the transformation of the genin part of glycosides of 20,24-epoxycycloartan-25-ols with retention of the carbohydrate constituents. Three 25-norglycosides have been synthesized from natural cyclosieversigenin glycosides, namely 16β-acetoxy-3β,6α-dihydroxy-20R,25-norcycloartan-20,24-olide 3-O-[O-α-L-arabinopyranosyl-(1→2)-β-D-xylopyranoside] 6-O-β-D-xylopyranoside (VIII), sodium 3β,6α,16β,20-tetrahydroxy-20R,25-norcycloartan-24-oate 6-O-β-D-glucopyranoside 3-O-β-D-xylopyranoside (XII), and 20R,25-norcycloartane-3β,6α,16β,20,24-pentaol 6-O-β-D-glucopyranoside 3-O-β-D-xylopyranoside (XIII).     

Ceramide and Cerebroside from the stem bark of Ficus mucuso (Moraceae)

Two new sphingolipids mucusamide (1) and mucusoside (2) have been isolated from methanol soluble part of the stem bark of Ficus mucuso WELW., together with fifteen known secondary metabolites including cellobiosylsterol (3), β-sitosterol (4), stigmasterol (5), β-sitosterol 3-O-β-D-glucopyranoside (6), lupeol acetate (7), ursolic acid (8), procatechuic acid (9), 2-methyl-5,7-dihydroxychromone 8-C-β-D-glucoside (10), apigenin (11), (-)-epicatechin (12), (+)-catechin (13), N-benzoyl-L-phenylalanilol (14), α-acetylamino-phenylpropyl α-benzoylamino-phenylpropionate (15), asperphenamate (16) and bejaminamide (17). Structures of compounds 1 and 2 were elucidated by spectroscopic analysis and chemical methods.     

Three new flavonoid glycosides, byzantionoside B 6'-O-sulfate and xyloglucoside of (Z)-hex-3-en-1-ol from Ruellia patula

Three new flavonoid glycosides, demethoxycentaureidin 7-O-β-D-galacturonopyranoside, pectolinarigenin 7-O-α-L-rhamnopyranosyl-(1?→4″)-β-D-glucopyranoside and 7-O-α-L-rhamnopyranosyl-(1?→4″)-β-D-glucuronopyranoside, a new megastigmane glucoside, byzantionoside B 6'-O-sulfate, and a new (Z)-hex-3-en-1-ol O-β-D-xylopyranosyl-(1″→2')-β-D-glucopyranoside, were isolated from leaves of Ruellia patula JACQ., together with 12 known compounds, β-sitosterol glucoside, vanilloside, bioside (decaffeoyl verbascoside), acteoside (verbascoside), syringin, benzyl alcohol O-β-D-xylopyranosyl-(1″→2')-β-D-glucopyranoside, cistanoside E, roseoside, phenethyl alcohol O-β-D-xylopyranosyl-(1″→2')-β-D-glucopyranoside, (+)-lyoniresinol 3α-O-β-D-glucopyranoside, isoacteoside and 3,4,5-trimethoxyphenol O-α-L-rhamnopyranosyl-(1″→6')-β-D-glucopyranoside. Their structures were elucidated by means of spectroscopic analyses.     

Three new megastigmane glucopyranosides from the Cardamine komarovii

Three new megastigmane glucopyranosides, komaroveside A [(3S,4R,5Z,7E)-3,4-dihydroxy-5,7-megastigmadien-9-one-3-O-β-D-glucopyranoside] (1), komaroveside B [(3S,4S,5S,6R,7E)-5,6-epoxy-3,4-dihydroxy-7-megastigmen-9-one-3-O-β-D-glucopyranoside] (2) and komaroveside C [(3S,4S,5S,6R,7E,9S)-5,6-epoxy-3,4,9-trihydroxy-7-megastigmen-3-O-β-D-glucopyranoside] (3) were isolated, together with eight known compounds, from Cardamine komarovii. The identification of these compounds and the elucidation of their structures were based on 1D- and 2D-NMR spectral data analysis. The isolated compounds were tested for their cytotoxicity against four human tumor cell lines (A549, SK-OV-3, SK-MEL-2, HCT15) in vitro using the sulforhodamine B bioassay.     

Inhibitory effects of constituents from Euphorbia lunulata on differentiation of 3T3-L1 cells and nitric oxide production in RAW264.7 cells

A new flavonol galactopyranoside, myricetin 3-O-(2',3'-digalloyl)-β-D-galactopyranoide (1), and 23 known constituents, including myricetin 3-O-(2'-galloyl)-β-D-galactopyranoide (2), myricitrin (3), myricetin (4), quercetin 3-O-(2', 3'-digalloyl)-β-D-galactopyranoide (5), quercetin 3-O-(2'-galloyl)-β-D-galactopyranoide (6), hyperin (7), isoquercetrin (8), quercetin (9), kaempferol (10), apigenin (11), luteolin (12), 3-O-methylquercetin (13), 5,7,2',5'-tetrahydroxyflavone (14), 1,3,4,6-tetra-O-galloyl-β-D-glucose (15), 1,2,6-tri-O-galloyl-β-D-glucose (16), 1,3,6-tri-O-galloyl-β-D-glucose (17), gallic acid (18), protocatechuic acid (19), 3,4,5-trimethoxybenzoic acid (20), 2,6-dihydroxyacetophenone (21), 3,3'-di-O-methylellagic acid (22), ellagic acid (23) and esculetin (24) were isolated from Euphorbia lunulata Bge. Their structures were determined by spectroscopic analysis. Isolated hydrolysable tannins, flavonoids, and flavonol galactopyranoside gallates showed significant inhibition of the differentiation of 3T3-L1 preadipocytes and triglyceride accumulation in maturing adipocytes, and nitric oxide production in RAW 264.7 cells.     

Antioxidant, anti-glycation and anti-inflammatory activities of phenolic constituents from Cordia sinensis

Nine compounds have been isolated from the ethyl acetate soluble fraction of C. sinensis, namely protocatechuic acid (1), trans-caffeic acid (2), methyl rosmarinate (3), rosmarinic acid (4), kaempferide-3-O-β-D-glucopyranoside (5), kaempferol-3-O-β-D-glucopyranoside (6), quercetin-3-O-β-D-glucopyranoside (7), kaempferide-3-O-α-L-rhamnopyranosyl (1→6)-β-D-glucopyranoside (8) and kaempferol-3-O-α-L-rhamno-pyranosyl (1→6)-β-D-glucopyranoside (9), all reported for the first time from this species. The structures of these compounds were deduced on the basis of spectroscopic studies, including 1D and 2D NMR techniques. Compounds 1-9 were investigated for biological activity and showed significant anti-inflammatory activity in the carrageen induced rat paw edema test. The antioxidant activities of isolated compounds 1-9 were evaluated by the DPPH radical scavenging test, and compounds 1, 2, 4 and 7-9 exhibited marked scavenging activity compared to the standard BHA. These compounds were further studied for their anti-glycation properties and some compounds showed significant anti-glycation inhibitory activity. The purity of compounds 2-5, 8 and 9 was confirmed by HPLC. The implications of these results for the chemotaxonomic studies of the genus Cordia have also been discussed.     

Kuwanon T and Sanggenon A Isolated from Morus alba Exert Anti-Inflammatory Effects by Regulating NF-κB and HO-1/Nrf2 Signaling Pathways in BV2 and RAW264.7 Cells

We previously investigated the methanolic extract of Morus alba bark and characterized 11 compounds from the extract: kuwanon G (1), kuwanon E (2), kuwanon T (3), sanggenon A (4), sanggenon M (5), sanggenol A (6), mulberofuran B (7), mulberofuran G (8), moracin M (9), moracin O (10), and norartocarpanone (11). Herein, we investigated the anti-inflammatory effects of these compounds on microglial cells (BV2) and macrophages (RAW264.7). Among them, 3 and 4 markedly inhibited the lipopolysaccharide (LPS)-induced production of nitric oxide in these cells, suggesting the anti-inflammatory properties of these two compounds. These compounds inhibited the production of prostaglandin E2, interleukin-6, and tumor necrosis factor-α, and the expression of inducible nitric oxide synthase and cyclooxygenase-2 following LPS stimulation. Pretreatment with 3 and 4 inhibited the activation of the nuclear factor kappa B signaling pathway in both cell types. The compounds also induced the expression of heme oxygenase (HO)-1 through the activation of nuclear factor erythroid 2-related factor 2. Suppressing the activity of HO-1 reversed the anti-inflammatory effects caused by pretreatment with 3 and 4, suggesting that the anti-inflammatory effects were regulated by HO-1. Taken together, 3 and 4 are potential candidates for developing therapeutic and preventive agents for inflammatory diseases.     

Three new triterpenoid saponins from Dianthus superbus

Three new triterpenoid saponins (1-3) were isolated from the dried aerial parts of Dianthus superbus L. (Caryophyllaceae). Their structures were established as 3-O-β-D-glucopyranosyl gypsogenic acid 28-O-[β-D-6-O-((3S)-3-hydroxyl-3-methylglutaryl)glucopyranosyl(1→6)]-β-D-glucopyranoside (1), 3-O-β-D-glucopyranosyl gypsogenic acid 28-O-[β-D-glucopyranosyl(1→3)][β-D-6-O-((3S)-hydroxyl-3-methylglutaryl)glucopyranosyl(1→6)]-β-D-glucopyranoside (2), 3-O-α-L-arabinopyranosyl-3β,16α-dihydroxyolean-12-en-23,28-dioic acid 28-O-[β-D-glucopyranosyl-(1→6)]-β-D-glucopyranoside (3), on the basis of various spectroscopic analyses and chemical degradations.     

Flavonoid constituents from the roots of Acanthopanax brachypus

Two new natural products, (3R)-5,7-dihydroxy-8-(2″-O-veratroyl-β-D-glucopyranosyl)-3-(4'-hydroxyphenyl)-6-methylchroman-4-one (1) and 4'-hydroxyisoflavone-7-O-[α-L-arabinopyranosyl-(1→6)-β-D-glucopyranoside] (2), along with eleven other known flavonoids, were isolated from the roots of Acanthopanax brachypus. Their structures were elucidated on the basis of spectroscopic and chemical evidence.     

3-Hydroxymethylglutaryl flavonol glycosides from a Mongolian and Tibetan medicine, Oxytropis racemosa

Three new flavonol 3-O-glycosides, rhamnetin 3-O-[(S)-3-hydroxy-3-methyl-glutaroyl(1→6)]-β-D-glucopyranoside (1), rhamnocitrin 3-O-[(S)-3-hydroxy-3-methylglutaroyl(1→6)]-β-D-glucopyranoside (2), and isorhamnetin 3-O-[(S)-3-hydroxy-3-methylglutaroyl(1→6)]-α-L-rhamnopyranosyl(1→2)-β-D-glucopyranoside (3), along with 13 known compounds, were isolated from Oxytropis racemosa TURCZ. Their structures were deduced by means of spectroscopic methods and chemical evidence. 2 and 6 showed cytotoxic activities against HCT-8 (IC?? 6.38 μM) and A549 (IC?? 5.20 μM), respectively.     

Flavonoids ofGnaphalium uliginosum

The herb low cudweed has yielded for the first time a new acylated flavone glycoside, for which the structure of 3′,4′,5,7-tetrahydroxy-6-methoxyflavone 7-O-(6″-O-caffeyl-β-D-glucopyranoside) has been established. In addition, 6-methoxyluteolin, 6-hydroxyluteolin 7-O-β-D-glucopyranoside, and scutellarein 7-O-β-D-glucopyranoside have been isolated. Identification was made on the basis of UV, IR, PMR, and mass spectra, the products of alkaline and acid hydrolyses, and the results of elementary analyses, melting points, and specific rotations.     

Chemical constituents of Asplenium ruta-muraria L

A phytochemical study of Asplenium ruta-muraria L. (Aspleniaceae) led to the isolation of a new caffeic acid glycoside, 2-O-caffeoyl-β-D-fructofuranosyl-(2?→?1)-α-D-glucopyranoside and an (α, β)-isomeric pair of 2E-caffeoyl-D-glucopyranoside, together with kaempferol-3-O-β-D-[6-E-caffeoyl-β-D-glucopyranosyl-(1?→?2)glucopyranoside]-7-O-β-D-glucopyranoside, 1-O-caffeoyl glycoside, sucrose, diploptene and β-sitosterol. Their structures were established by means of MS and capillary NMR techniques. Additionally, aromatase inhibitory activity of the extracts and phenolic compounds was evaluated.     

Triterpene glycosides of Astragalus and their genins. XXIV. Cycloorbicoside G from Astragalus orbiculatus

A bisdesmosidic glycoside — cycloorbicoside G — has been isolated from the epigeal parts of the plantAstragalus orbiculatus Ledeb. (Leguminosae), and on the basis of chemical transformations and spectral characteristics its structure has been established as (23R,24S)-16β,23;16α,24-diepoxycycloartane-3β,7β,25-triol 25-O-β-D-glucopyranoside 3-O-β-D-xylopyranoside.     

Chemical constituents and antibacterial activity of Melastoma malabathricum L

The aqueous methanolic extracts of Melastoma malabathricum L. exhibited antibacterial activity when assayed against seven microorganisms by the agar diffusion method. Solvent fractionation afforded active chloroform and ethyl acetate fractions from the leaves and the flowers, respectively. A phytochemical study resulted in the identification of ursolic acid (1), 2α-hydroxyursolic acid (2), asiatic acid (3), β-sitosterol 3-O-β-D-glucopyranoside (4) and the glycolipid glycerol 1,2-dilinolenyl-3-O-β-D-galactopyanoside (5) from the chloroform fraction. Kaempferol (6), kaempferol 3-O-α-L-rhamnopyranoside (7), kaempferol 3-O-β-D-glucopyranoside (8), kaempferol 3-O-β-D-galactopyranoside (9), kaempferol 3-O-(2″,6″-di-O-E-p-coumaryl)-β-D-galactopyranoside (10), quercetin (11) and ellagic acid (12) were found in the ethyl acetate fraction. The structures of these compounds were determined by chemical and spectral analyses. Compounds 1-4, the flavonols (6 and 11) and ellagic acid (12) were found to be active against some of the tested microorganisms, while the kaempferol 3-O-glycosides (7-9) did not show any activity, indicating the role of the free 3-OH for antibacterial activity. Addition of p-coumaryl groups results in mild activity for 10 against Staphylococcus aureus and Bacillus cereus. Compounds 2-5, 7 and 9-12 are reported for the first time from M. malabathricum. Compound 10 is rare, being reported only once before from a plant, without assignment of the double bond geometry in the p-coumaryl moiety.     

Terpene glycosides from the roots of Sanguisorba officinalis L. and their hemostatic activities

Guided by a hemostasis bioassay, seven terpene glycosides were isolated from the roots of Sanguisorba officinalis L. by silica gel column chromatography and preparative HPLC. On the grounds of chemical and spectroscopic methods, their structures were identified as citronellol-1-O-α-L-arabinofuranosyl-(1→6)-β-D-glucopyranoside (1), geraniol-1-O-α-L-arabinofuranosyl-(1→6)-β-D-glucopyranoside (2), geraniol-1-O-α-Larabinopyranosyl-(1→6)-β-D-glucopyranoside (3), 3β-[(α-L-arabinopyranosyl)oxy]-19α-hydroxyolean-12-en-28-oic acid 28-β-D-glucopyranoside (4), 3β-[(α-L-arabinopyranosyl)-oxy]-19α-hydroxyurs-12-en-28-oic acid 28-β-D-glucopyranoside (ziyu-glycoside I, 5), 3β,19α-hydroxyolean-12-en-28-oic acid 28-β-D-glucopyranoside (6) and 3β,19α-dihydroxyurs-12-en-28-oic acid 28-β-D-glucopyranoside (7). Compound 1 is a new mono-terpene glycoside and compounds 2, 3 and 5 were isolated from the Sanguisorba genus for the first time. Compounds 1–7 were assayed for their hemostatic activities with a Goat Anti-Human α2-plasmin inhibitor ELISA kit, and ziyu-glycoside I (5) showed the strongest hemostatic activity among the seven terpene glycosides. This is the first report that ziyu-glycoside Ι has strong hemostatic activity.     

A new steroidal glycoside from the Ophiopogon japonicus Ker-Gawler (Liliaceae)

A new steroidal glycoside (1), (25R)-14α, 17α-hydroxyspirost-5-en-3β-yl 3-O-α-L-rhamnpyranosyl-(1 → 2)-β-D-glucopyranosyl-(1 → 3)-β-D-glucopyranoside, together with three known steroidal glycosides, (25R)-3β-hydroxyspirost-5-en-1β-yl-3-O-α-L-rhamnopyranosyl-(1 → 2)-O-β-D-xylopyranosyl-(1 → 3)-α-L-arabinopyranoside (2), Cixi-ophiopogon B (3) and Cixi-ophiopogon A (4), were obtained from the tuberous roots of Ophiopogon japonicus (Liliaceae). Compound 2 was isolated from the Ophiopogon genus for the first time. Their structures were identified on the basis of extensive mass and nuclear magnetic resonance spectroscopic analysis.     

Phenolic compounds from the aerial parts of Diplomorpha canescens

One new C-methyl flavanone glucoside, farrerol 4'-O-β-D-glucopyranoside (1) was isolated from the aerial parts of Diplomorpha canescens (MEISN.) C. A. MEYER. Fourteen known phenolic compounds such as farrerol (2), luteolin 7-methyl ether 5-O-β-D-glucopyranoside (3), (-)-pinoresinol (4), (-)-lariciresinol (5), (-)-dihydrosesamin (6), (±)-dehydrodiconiferyl alcohol (7), rutarensin (8), umbelliferone (9), coniferyl aldehyde (10), sinapyl aldehyde (11), p-coumaric acid methyl ester (12), p-hydroxybenzaldehyde (13), p-hydroxyacetophenone (14) and syringaldehyde (15) were also isolated for the first time from this plant. Structure of 1 was determined on the basis of spectroscopic data including two dimensional (2D)-NMR, circular dichroism (CD) and by the application of Klyne's rule.     

Steroid glycosides ofNicotiana tabacum seeds I. The structures of nicotianosides A,B, and E

Two steroid glycosides of the spirostan series — nicotianosides A and B — and one glycoside of the furostan series — nicotianoside E — have been isolated from the seeds ofNicotiana tabacum L. Nicotianoside A is (25S)-5α-spirostan-3β-ol 3-O-β-D-glucopyranoside, nicotianoside B is (25S)-5β-spirostan-3β-ol 3-O-[O-α-L-rhamnopyranosyl-(1→2)-gb-D-glucopyranoside], and nicotianoside E is (25S)-5α-furostan-3β,22α,26-triol 26-O-β-glucopyranoside 3-O-[O-α-L-rhamnopyranosyl-(1→2)-β-D-glucopyranoside].     

Flavonoids from Halostachys caspica and their antimicrobial and antioxidant activities

Seven flavonoids have been isolated from the aerial parts of Halostachys caspica C. A. Mey. (Chenopodiaceae) for the first time. By means of physicochemical and spectrometric analysis, they were identified as luteolin (1), chrysin (2), chrysin 7-O-β-D-glucopyranoside (3), quercetin (4), quercetin 3-O-β-D-glucopyranoside (5), isorhamentin-3-O-β-D-glucopyranoside (6), and isorhamentin-3-O-β-D-rutinoside (7). All flavonoids were evaluated to show a broad antimicrobial spectrum of activity on microorganisms including seven bacterial and one fungal species as well as pronounced antioxidant activity. Among them, the aglycones with relatively low polarity had stronger bioactivity than their glycosides. The results suggested that the isolated flavonoids could be used for future development of antimicrobial and antioxidant agents, and also provided additional data for supporting the use of H. caspica as forage.     

A new abietene diterpene and other constituents from Kaempferia angustifolia Rosc

A new abietene diterpene, kaempfolienol (5S,6S,7S,9S,10S,11R,13S-abiet-8(14)-enepenta-6,7,9,11,13-ol, 1), was isolated from a rhizome extract of Kaempferia angustifolia Rosc. along with the known compounds crotepoxide, boesenboxide, zeylenol, 2'-hydroxy-4,4',6'-trimethoxychalcone, (24S)-24-methyl-5α-lanosta-9(11),25-dien-3β-ol, β-sitosterol and β-sitosterol-3-O-β-D-glucopyranoside. The structures of all compounds were elucidated on the basis of mass spectroscopic and NMR data. Zeylenol (2), the major constituent of the plant, was derivatized into diacetate, triacetate and epoxide derivatives through standard organic reactions. The cytotoxic activity of compounds 1, 2 and the zeylenol derivatives was evaluated against the HL-60, MCF-7, HT-29 and HeLa cell lines.