New isoflavone glycosides from <Emphasis Type="Italic">Iris spuria</Emphasis> L. (Calizona) cultivated in Egypt

Two new isoflavone glycosides, tectorigenin 7-O-β-d-glucopyranoside-4′-O-[β-d-glucopyranosyl-(1″″ → 6′′′)-β-d-glucopyranoside] (1) and iristectorigenin B 4′-O-[β-d-glucopyranosyl-(1′′′ → 6″)-β-d-glucopyranoside] (2), together with 11 known compounds, including six isoflavones, tectorigenin 7-O-β-d-glucopyranoside-4′-O-β-d-glucopyranoside (3), tectorigenin 4′-O-[β-d-glucopyranosyl-(1′′′ → 6″)-β-d-glucopyranoside] (4), tectorigenin 7-O-β-d-glucopyranoside (5), genistein 7-O-β-d-glucopyranoside (6), tectorigenin 4′-O-β-d-glucopyranoside (7), and tectorigenin (8); two phenolic acid glycosides, vanillic acid 4-O-β-d-glucopyranoside (9) and glucosyringic acid (10); a phenylpropanoid glycoside, E-coniferin (11); an auronol derivative, maesopsin 6-O-β-d-glucopyranoside (12); and a pyrrole derivative, 4-(2-formyl-5-hydroxymethylpyrrol-1-yl) butyric acid (13), were isolated from fresh Iris spuria (Calizona) rhizomes. The structures of these compounds were established on the basis of spectroscopic and chemical evidence. Inhibitory effects on the activation of Epstein–Barr virus early antigen were examined for compounds 1–8 and 12.     

Flavonol glycosides from the aerial parts of<Emphasis Type="Italic">Aceriphyllum rossii</Emphasis> and their antioxidant activities

The methanol extract obtained from the aerial parts ofAceriphyllum rossii (Saxifragaceae) was fractionated into ethyl acetate (EtOAc),n-BuOH and H₂O layers through solvent fractionation. Repeated silica gel column chromatography of EtOAc andn-BuOH layers afforded six flavonol glycosides. They were identified as kaempferol 3-O-β-D-glucopyranoside (astragalin,1), quercetin 3-O-β-D-glucopyranoside (isoquercitrin,2), kaempferol 3-O-α-L-rhamnopyranosyl (1→6)-β-D-glucopyranoside (3), quercetin 3-O-α-L-rhamnopyranosyl (1→6)-β-D-glucopyrano-side (rutin,4), kaempferol 3-O-[α-L-rhamnopyranosyl (1→4)-α-L-rhamnopyranosyl (1→6)-β-D-glucopyranoside] (5) and quercetin 3-O-[α-L-rhamnopyranosyl (1→4)-α-L-rhamnopyranosyl (1→6)-β-D-glucopyranoside] (6) on the basis of several spectral data. The antioxidant activity of the six compounds was investigated using two free radicals such as the ABTS free radical and superoxide anion radical. Compound1 exhibited the highest antioxidant activity in the ABTS2,2-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) radical scavenging method. 100 mg/L of compound1 was equivalent to 72.1±1.4 mg/L of vitamin C, and those of compounds3 and5 were equivalent to 62.7±0.5 mg/L and 54.3±1.3 mg/L of vitamin C, respectively. And in the superoxide anion radical scavenging method, compound5 exhibited the highest activity with an IC₅₀ value of 17.6 ± 0.3 μM. In addition, some physical and spectral data of the flavonoids were confirmed.     

Five new glycosides from <Emphasis Type="Italic">Hypericum erectum</Emphasis> Thunb.

Five new glycosides, quercetin 3′-O-β-d-galactopyranoside (1), quercetin 3-O-(2″-acetyl)-β-d-glucopyranoside (2), 4,6-dihydroxy-2-methoxyphenyl 1-O-β-d-glucopyranoside (3), 4-hydroxy-2,6-dimethoxyphenyl 1-O-α-l-rhamnopyranosyl (1 → 6)-β-d-glucopyranoside (4) and 3-methyl-but-2-en-1-yl β-d-glucopyranosyl (1 → 6)-β-d-glucopyranoside (5), were isolated from Hypericum erectum Thunb. Their structures were established on the basis of spectral and chemical data.     

A dimeric triterpenoid glycoside and flavonoid glycosides with free radical-scavenging activity isolated from <Emphasis Type="Italic">Rubus rigidus</Emphasis> var. <Emphasis Type="Italic">camerunensis</Emphasis>

The aerial part of Rubus rigidus var. camerunensis (Rosaceae) is used to treat respiratory and cardiovascular disorders in the Cameroonian traditional medicine. The ethanol extract exhibited more potent antioxidant activity (E_maxs of 119% and 229% activity on DPPH and β-carotene test) than aqueous extract. Bioactivity-guided fractionation of the ethanol extract based on free radical-scavenging assay (DPPH assay) afforded five flavonoid glycosides (four flavonol glycosides and an anthocyanin) and three glucosides of 19α-hydroxyursane-type triterpenoid (two monomeric and one dimeric triterpenoids). The flavonoids were identified as kaempferol 3-O-(2″-O-E-p-coumaroyl)-β-D-glucopyranoside (1), kaempferol-3-O-β-D-glucopyranoside (astragalin, 2), kaempferol-3-O-α-L-arabinofuranoside (juglanin, 3), quercetin-3-O-β-D-glucopyranoside (isoquercitrin, 4), pelargonidin-3-O-β-D-glucopyranoside (callistephin, 5). The three triterpenoids were 2α, 3β, 19α, 23-tetrahydroxyurs-12-ene-28-O-β-D-glucopyranosyl ester (nigaichigoside F₁, 6), 2α, 3β, 19α-trihydroxyurs-12-ene-23-carboxyl-28-O-β-D-glucopyranosyl ester (suavissimoside R₁, 7) as monomeric triterpenoids and coreanoside F₁ (8) as a dimeric triterpenoid. The flavonoids exhibited potent antioxidant activities (66 to 93.56% against DPPH radical) and they were also active on β-carotene test. Coreanoside F₁ exhibited a 63% antioxidant activity, meanwhile the other two triterpenoids showed a weak activity. Three important facts on structure-activity relationship were observed: Compound 8, a dimeric triterpenoid glycoside, strongly enhanced antioxidant activity of its monomers, compound 3 with 3-O-α-L-arabinofuranyl has much more potent activity than compound 2 with 3-O-β-D-glucopyranosyl, and antocyanin (5) is more potent than its corresponding flavonol glycosides.     

Iridoid glucoside, (3<Emphasis Type="Italic">R</Emphasis>)-oct-1-en-3-ol glycosides,and phenylethanoid from the aerial parts of <Emphasis Type="Italic">Caryopteris incana</Emphasis>

Eleven compounds of interest were isolated from the aerial parts of Caryopteris incana, specifically a new acyl derivative (3) of 8-O-acetylharpagide, two new (3R)-oct-1-en-3-ol glycosides (5, 6), and 6-O-caffeoylphlinoside A (11) along with seven known compounds, 8-O-acetylharpagide (1), 6′-O-p-coumaroyl-8-O-acetylharpagide (2), (3R)-oct-1-en-3-ol (matsutake alcohol) O-α-l-arabinopyranosyl-(1″ → 6′)-O-β-d-glucopyranoside (4), apigenin 7-O-neohesperidinoside (7), 6′-O-caffeoylarbutin (8), and two phenylethanoids, leucosceptoside A (9) and phlinoside A (10). This paper deals with structural elucidation of the new compounds.     

Lignan and flavonoid glycosides from <Emphasis Type="Italic">Urtica laetevirens</Emphasis> Maxim.

A new compound named pinoresinol 4-O-α-l-rhamnopyranosyl (1 → 2)-β-d-glucopyranoside (1) together with six known compounds, isolariciresinol 9-O-β-D-glucopyranoside (2), apigenin 6,8-di-C-β-d-glucopyranoside (3), luteolin 7-O-neohesperidoside (4), luteolin 7-O-β-d-glucopyranoside (5), 5-methoxyluteolin 7-O-β-d-glucopyranoside (6), and rutin (7), were isolated from the aerial parts of Urtica laetevirens Maxim. All of the above compounds were isolated from this plant for the first time.     

Baimantuoluosides D-G,four new withanolide glucosides from the flower of <Emphasis Type="Italic">Datura metel</Emphasis> L.

In our search for bioactive anti-psoriasis compounds from the flower of Datura metel L, we isolated four new withanolide glucosides, baimantuoluosides D, E, F and G (1–4). The structures of the new compounds are (5α,6α,7β,22R)-5,6,7,27-tetrahydroxy-1-oxowitha-2,24-dien-27-O-β-D-glucopyranoside (1), (5α,6β,7α,22R)-5,6,7,27-tetrahydroxy-1-oxowitha-2,24-dien-27-O-β-D-glucopyranoside (2), (5α,6β,7α,12β,22R)-5,6,7,12,27-pentahydroxy-1-oxowitha-2,24-dien-27-O-β-D-glucopyranoside (3), and (5α,6β,22R)-5,6,27-trihydroxy-1-oxowitha-2,24-dien-27-O-β-D-glucopyranoside (4) on the basis of chemical and physicochemical evidence.     

New glycosides from <Emphasis Type="Italic">Dracocephalum tanguticum</Emphasis> maxim

Four new glycosides, luteolin-7-methoxy-3′-O-(3″-O-acetyl)-β-D-gluco pyranuronic acid-6″-methyl ester (1), benzyl-6-[(2E)-2-butenoate]-β-D-glucopyranoside (2), 2-methoxy-4-(2-propen-1-yl)penyl-6-acetate-β-D-glucopyranoside (3), and 2-methoxy-4-(2-propen-1-yl)penyl-6-[(2E)-2-butenoate]-β-D-glucopyranoside (4), along with benzyl-β-D-glucopyranoside (5), 2-methoxy-4-(2-propen-1-yl)penyl-β-D-glucopyranoside (6), and pectolarigenin (7), were isolated from the whole plant of Dracocephalum tanguticum Maxim. The structures of 1-4 were elucidated by detailed spectroscopic analyses, including HR-ESI-MS and 2D NMR spectroscopic data. The inhibitory effects against nitric oxide production in LPS-stimulated RAW264.7 cells of all seven compounds were also evaluated.     

(<Emphasis Type="Italic">Z</Emphasis>)-3-Hexenyl diglycosides from <Emphasis Type="Italic">Spermacoce laevis</Emphasis> Roxb.

A new (Z)-3-hexenyl O-β-d-glucopyranosyl-(1→6)-β-d-glucopyranoside was isolated from the aerial part of Spermacoce laevis, along with 17 known compounds: (6S,9R)-roseoside, (Z)-3-hexenyl O-β-d-glucopyranoside, (Z)-3-hexenyl O-α-l-rhamnopyranosyl-(1→6)-β-d-glucopyranoside, (Z)-3-hexenyl O-α-l-arabinopyranosyl-(1→6)-β-d-glucopyranoside, phenyethyl O-β-d-glucopyranoside, phenyethyl O-α-l-arabinopyranosyl-(1→6)-β-d-glucopyranoside, phenyethyl O-α-l-rhamnopyranosyl-(1→6)-β-d-glucopyranoside, benzyl O-α-l-arabinopyranosyl-(1→6)-β-d-glucopyranoside, benzyl O-β-d-xylopyranosyl-(1→6)-β-d-glucopyranoside, asperuloside, 6α-hydroxyadoxoside, asperulosidic acid, kaempferol 3-O-β-d-glucopyranoside, kaempferol 3-O-rutinoside, quercetin 3-O-β-d-galactopyranoside, quercetin 3-O-α-l-rhamnopyranosyl-(1→6)-β-d-galactopyranoside, and rutin. The structure determinations were based on physical data and spectroscopic evidence.     

Microbial metabolites of 8-prenylnaringenin,an estrogenic prenylflavanone

Microbial metabolism studies of the phyto-estrogen (±)-8-prenylnaringenin (8-PN) (1) has led to the isolation of three pairs of metabolites (2–4). The structures of these compounds were identified as 5,4′-dihydroxy-7,8-[2-(1-hydroxy-1-methylethyl)-2,3-dihydrofurano]flavanones (2), 8-prenylnaringenin 7-O-β-D-glucopyranosides (3), and 8-prenylnaringenin 7-O-β-D-(6‴-O-α-hydroxypropionyl)-glucopyranosides (4) on the basis of the spectroscopic analysis.     

Constituents of the root of <Emphasis Type="Italic">Anemone tomentosa</Emphasis>

A new diterpene glycoside, tomentoside I (1), along with eleven known compounds, including the four coumarins, 4,5-dimethoxyl-7-methylcoumarin (2), 4,7-dimethoxyl-5-methylcoumarin (3), isofraxidin (4) and fraxidin (5) as well as the seven triterpenoids, oleanolic acid (6), oleanolic acid 3-O-α-L-arabinopyranoside (7), oleanolic acid 3-O-β-D-galactopyranosyl-(1→3)-β-D-glucopyranoside (8), hederagenin 3-O-α-L-arabinopyranoside (9), betulinic acid (10), 18-hydroxyursolic acid (11) and 2α,3β,23-trihydroxyurs-12-en-28-oic acid (12) were isolated from the ethanolic extract of the root of Anemone tomentosa and their chemical structures were elucidated by spectroscopic methods. The antimicrobial activities of compounds 1–12 were measured using the agar disc-diffusion method. Also, their antioxidant activities against 1,1-diphenyl-2-picrylhydrazyl (DPPH) were evaluated.     

A new abietic acid-type diterpene glucoside from the needles of <Emphasis Type="Italic">Pinus densiflora</Emphasis>

From the ethyl acetate fraction of the methanol extract of the needles of Pinus densiflora (Pinaceae), a new diterpenoid glucoside [9α,13α-epoxy-8β,14β-dihydroxy-abietic acid-18-O-β-d-glucopyranoside] (1), two flavonoid glucosides [kaempferol 3-O-β-d-glucoside (2) and 6-C-methyl kaempferol 3-O-β-d-glucoside (3)], and two monoterpenoid glucosides [bornyl 6-O-α-Larabinofuranosyl (1→6)-β-d-glucopyranoside (4) and bornyl 6-O-β-d-apiofuranosyl (1→6)-β-d-glucopyranoside (5)] were isolated and characterized on the basis of spectral analysis. Of all the compounds, 2 and 3 showed peroxynitrite scavenging activity.     

Antioxidant Activity of Anthraquinones and Flavonoids from Flower ofReynoutria sachalinensis

Bioassay-guided fractionation of methanol extract ofReynoutria sachalinensis flower using DPPH assay has led to the isolation of three anthraquinones and three flavonoids. Their structures were identified as emodin (1), emodin-8-O-β-D-glucopyranoside (2), physcion-8-O-β-D-glucopyranoside (3), quercetin-3-O-α-L-arabinofuranoside (4), quercetin-3-O-α-D-galactopyranoside (5), and quercetin-3-O-β-D-glucuronopyranoside (6) by comparing their physicochemical and spectral data with those published in literatures. All isolated compounds were evaluated for antioxidant activities with free radical 1, 1-diphenyl-2-picrylhydrazyl (DPPH) scavenging, superoxide radical scavenging and Cu²⁺-mediated low density lipoprotein (LDL) oxidation assay. The results demonstrated that three flavonoids,4, 5, and6 had remarkable antioxidant activities with the IC₅₀ values of 64.3, 54.7, and 46.2 μM (DPPH scavenging), the IC₅₀ values of 6.0, 6.7, and 4.4 μM (superoxide radical scavenging) and the IC₅₀ values of 3.8, 3.2, and 5.4 μM against LDL oxidation, respectively.     

New triterpene saponins from <Emphasis Type="Italic">Stenocereus eruca</Emphasis> (Cactaceae)

Two new triterpene saponins, named stellatoside B (1) and erucasaponin A (2), were isolated from a cactaceous plant, Stenocereus eruca A. C. Gibson & K. E. Horak (Machaerocereus eruca Br. & R.). The structures of 1 and 2 were elucidated as 3-O-β-d-xylopyranosyl-(1→2)-β-d-glucopyranosyl-(1→2)-β-d-glucuronopyranosyl stellatogenin and 3-O-α-l-rhamnopyranosyl-(1→2)-[α-l-rhamnopyranosyl-(1→3)]-β-d-glucuronopyranosyl betulinic acid 28-O-α-l-rhamnopyranosyl ester, respectively, on the basis of their spectroscopic data.     

Anti-inflammatory phenylpropanoid glycosides from <Emphasis Type="Italic">Clerodendron trichotomum</Emphasis> leaves

The chromatographic separation of MeOH extract from Clerodendron trichotomum Thunberg leaves led to the isolation of three phenylpropanoid compounds. Using spectroscopic methods, the structures of these compounds were determined as β-(3′, 4′-dihydroxyphenyl)ethyl-O-α-L-rhamnopyranosyl (1→3)-β-D-(4-O-caffeoyl)-glucopyranoside, acteoside (verbascoside) (1), β-(3′, 4′-dihydroxyphenyl)ethyl-O-α-L-rhamnopyranosyl (1→3)-β-D-(6-O-caffeoyl)-glucopyranoside, isoacteoside (2), β-(3′, 4′-dihydroxyphenyl) ethyl-O-α-L-rhamnopyranosyl (1→3)-β-D-glucopyranoside, and decaffeoylacteoside (3). We measured the anti-inflammatory activity of these three phenylpropanoid compounds both in vitro (DPPH Reduction Assay, TBARS Assay on Cu ²⁺-induced oxidized LDL, PGE₂ assay) and in vivo (acetic acidinduced vascular permeability in mice and carrageenan-induced hind paw edema in rats). 80% methanol fraction and acteoside had the activity.     

Novel phenolic glycosides,adenophorasides A–E,from Adenophora roots

Five novel phenolic glycosides, adenophorasides A (1), B (2), C (3), D (4), and E (5), were isolated from commercial Adenophora roots, together with vanilloloside (6), 3,4-dimethoxybenzyl alcohol 7-O-β-d-glucopyranoside (7), and lobetyolin (8). The structures of the new compounds (1–5) were characterized as 4-hydroxy-3-methoxyphenylacetonitrile 4-O-β-d-glucopyranoside (1), 4-hydroxy-3-methoxyphenylacetonitrile 4-O-β-d-glucopyranosyl-(1→6)-β-d-glucopyranoside (2), 4-hydroxy-3-methoxyphenylacetonitrile 4-O-α-l-rhamnopyranosyl-(1→6)-β-d-glucopyranoside (3), 4-hydroxyphenylacetonitrile 4-O-β-d-glucopyranosyl-(1→6)-β-d-glucopyranoside (4), and 4-hydroxy-3-methoxybenzyl alcohol 4-O-β-d-glucopyranosyl-(1→6)-β-d-glucopyranoside (5), respectively, by means of spectroscopic and chemical analyses.     

A new phenolic glycoside syringate from the bark of <Emphasis Type="Italic">Juglans mandshurica</Emphasis> MAXIM. var. <Emphasis Type="Italic">sieboldiana</Emphasis> MAKINO

A new phenolic glycoside syringate, 4′-hydroxy-2′,6′-dimethoxyphenol 1-O-β-d-(6-O-syringoyl) glucopyranoside (1), together with two known ones, 2′-hydroxy-4′-methoxyphenol 1-O-β-d-(6-O-syringoyl) glucopyranoside (2) and 4′-hydroxy-2′-methoxyphenol 1-O-β-d-(6-O-syringoyl) glucopyranoside (3), were isolated from the bark of Juglans mandshurica MAXIM. var. sieboldiana MAKINO. Their structures were established on the basis of spectral and chemical data.     

Two new triterpenoid saponins from rhizome of <Emphasis Type="Italic">Anemone raddeana</Emphasis> Regel

Two new 27-hydroxyoleanolic acid-type triterpenoid saponins, raddeanoside Ra (1) and raddeanoside Rb (2), were isolated from the rhizome of Anemone raddeana Regel. The structures of the two compounds were elucidated to be 27-hydroxyoleanolic acid 3-O-β-d-glucopyranosyl-(1 → 4)-α-l-arabinopyranoside (1) and 27-hydroxyoleanolic acid 3-O-α-l-arabinopyranosyl-(1 → 3)-α-l-rhamnopyranosyl-(1 → 2)-α- l-arabinopyranoside (2) on the basis of chemical and spectral evidence.     

Triterpenoic acids of Prunella vulgaris var. lilacina and their cytotoxic activities In Vitro

The column chromatographic separation of the MeOH extract from the aerial parts of Prunella vulgaris var. lilacina Nakai led to the isolation of fifteen triterpenoic acids (2–6, 9–13, 16–20), four flavonoids (14, 21–23), four phenolics (7, 8, 15, 24), and a diterpene (1). Their structures were determined by spectroscopic methods to be trans-phytol (1), oleanic acid (2) ursolic acid (3), 2α,3α,19α-trihydroxyurs-12en-28oic acid (4), 2α,3α-dihydroxyurs-12en-28oic acid (5), maslinic acid (6), caffeic acid (7), phydroxy cinnamic acid (8), 2α,3α,19α,23-tetrahydroxyurs-12en-28oic acid (9), 2α,3α,23-trihydroxyurs-12en-28oic acid (10), 2α,3β-dihydroxyurs-12en-28oic acid (11), 2α,3β,24-trihydroxyolea-12en-28oic acid (12), (12R, 13S)-2α,3α,24,trihydroxy-12,13-cyclo-taraxer-14-en-28oic acid (13), quercertin 3-O-β-D-glucopyranoside (14), rosmarinic acid (15), 2α,3α,24-trihydroxyurs-12,20(30)-dien-28oic acid (16), 2α,3α,24-trihydroxyolea-12en-28oic acid (17), 2α,3β,19α,24-tetrahydroxyurs-12en-28oic acid 28-O-Dglucopyranoside (18), 2α,3α,19α,24-tetrahydroxyurs-12en-28oic acid 28-O-D-glucopyranoside (19), prunvuloside A (20), kaempferol 3-O-α-L-rhamnopyranosyl(1→6)-β-D-glucopranoside (21), kaempferol 3-O-β-D-glucopyranoside (22), quercertin 3-O-α-L-rhamnopyranosyl(1→6)-β-D-glucopyranoside (23), and 2-hydroxy-3-(3’,4’-dihydroxyphenly)propanoic acid (24). Compounds 1, 8–12, 17, 21, 23, and 24 were isolated from this plant source for the first time. The isolated compounds were evaluated for their cytotoxicity against A549, SK-OV-3, SK-MEL-2, and HCT15 cells in vitro using the sulforhodamin B bioassay (SRB) method. Compound 3 exhibited moderate cytotoxic activity against A549, SK-OV-3, SK-MEL-2, and HCT15 cells, with ED₅₀ values of 3.71, 3.65, 13.62, and 5.44 μM, respectively.     

New flavonol glycosides from leaves ofSymplocarpus renifolius

A study was carried out to evaluate flavonol glycosides in leaves ofSymplocarpus renifolius (Araceae). From the water fraction of the MeOH extract, three new flavonol glycosides were isolated along with three known compounds, kaempferol-3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-7-O-β-D-glucopyranoside, quercetin-3-O-β-D-glucopyranosy-l-(1→2)-β-D-glucopyranoside, and caffeic acid. The structures of the new flavonol glycosides were elucidated by chemical and spectral analyses as quercetin-3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-7-O-β-D-glucopyranoside, isorhamnetin-3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-7-O-β-D-glucopyranoside, and quercetin-3-O-β-D-glucopyranosyl-(1→2)-β-D-glucopyranosyl-7-O-(6^IIII-trans-caffeoyl)-β-D-glucopyranoside.