A new <Emphasis Type="Italic">Erythrina</Emphasis> alkaloid from <Emphasis Type="Italic">Erythrina herbacea</Emphasis>

A new Erythrina alkaloid, 10-hydroxy-11-oxoerysotrine (1), has been isolated from the flowers of Erythrina herbacea together with five known compounds: erytharbine (2), 10,11-dioxoerysotrine (3), erythrartine (4), erysotramidine (5) and erysotrine-N-oxide (6). The structure of the new compound was elucidated on the basis of its spectral data, including 2-D NMR and mass (MS) spectra. The new compound is a rare C-10 oxygenated Erythrina alkaloid. The antioxidant activities of the isolated compounds 1–6 were evaluated by scavenging with peroxynitrite.     

A new lignan glycoside from <Emphasis Type="Italic">Juniperus rigida</Emphasis>

A new lignan glycoside, named juniperigiside (1) was isolated from the CHCl₃ soluble fraction of the MeOH extract of stems and leaves of Juniperus rigida S.et Z. Compound 1 was identified by 1D- and 2D-NMR spectroscopy as well as CD analysis as (2R,3S)-2,3-dihydro-7-methoxy-2-(4′-hydroxy-3′-methoxyphenyl)-3-hydroxymethyl-5-benzofuranpropanol 4′-O-(3-O-methyl)-α-L-rhamnopyranoside. Five known lignans, icariside E4 (2), desoxypodophyllotoxin (3), savinin (4), thujastandin (5), and (−)-nortrachelogenin (6) in addition to five known labdane diterpenes including trans-communic acid (7), 13-epi-torulosal (8), 13-epi-cupressic acid (9), imbricatoric acid (10), and isocupressic acid (11) were also isolated and their structures were characterized by comparing their spectroscopic data with those in the literature. All compounds were isolated for the first time from this plant, and 5 and 6 were first reported from the genus Juniperus. The isolated compounds were tested for cytotoxicity against four human tumor cell lines in vitro using a Sulforhodamin B bioassay. Compounds 3, 4, 7, and 8 showed considerable cytotoxicity against four human cancer cell lines in vitro.     

Chemical constituents of <Emphasis Type="Italic">Melandrium firmum</Emphasis> Rohrbach and their anti-inflammatory activity

In our ongoing search for anti-inflammatory agents originating from Korean medicinal plants, we found that the hexane and BuOH fractions of the MeOH extract from the whole plants of Melandrium firmum Rohrbach inhibited 5-lipoxygenase (5-LOX) activity. By activity-guided fractionation, eleven compounds, α-spinaterol (1), ursolic acid (2), ergosterol peroxide (3), α-spinaterol glucoside (4), 2-methoxy-9-β-D-ribofuranosyl purine (5), aristeromycin (6), ecdysteron (7), polypodoaurein (8), (-)-bornesitol (9), mannitol (10) and cytisoside (11) were isolated from the hexane and BuOH fractions using column chromatography. Compounds 2, 5, 6, 8, 9, 10 and 11 were isolated for the first time from this plant. Compounds 1, 3, 4 and 7 inhibited 5-LOX activity with IC₅₀ values of 21.04 μM, 42.30 μM, 32.82 μM, and 17.18 μM, respectively. Ming Shan Zheng and Nam Kyung Hwang contributed equally to this work.     

A new pyrrole alkaloid isolated from<Emphasis Type="Italic">Arum palaestinum</Emphasis> Boiss. and its biological activities

The phytochemical analysis of the ethyl acetate fraction ofArum palaestinum Boiss. (Araceae) led to the isolation and identification of a new polyhydroxy alkaloid compound; (S)-3,4,5-trihydroxy-1H-pyrrol-2(5H)-one (1), and other five known compounds; caffeic acid (2), isoorientin (3), luteolin (4) and vicenin II (5), as well as the rare compound 3,6,8-trimethoxy, 5,7,3′,4′-tetrahydroxy flavone (6). The structural elucidations of all the compounds were based on spectroscopic data (¹H- and¹³C-NMR, DEPT, HSQC, HMBC and NOE difference techniques) and comparison with literature data. Investigation of the antioxidant activity of the ethyl acetate fraction indicated its strong scavenging capacity for 1, 1-diphenyl-2-picrylhydrazyl (DPPH) radicals (SC₅₀ 3.1 ±0.82 μg/mL). Moreover, the treatment of different human cancer cell lines with the ethyl acetate fraction led to dose-dependant suppression in the proliferation of both breast carcinoma cells (MCF-7; IC₅₀ 59.09±4.1 μg/mL) and lymphoblastic leukemia cells (1301; IC₅₀ 53.1±2.9 μg/mL); however, it was found to have no effect on the growth of hepatocellular carcinoma cells (Hep G2).     

A new lignan from <Emphasis Type="Italic">Aphanamixis polystachya</Emphasis>

A new lignan, polystachyol (1), two lignan glycosides, lyoniside (2) and nudiposide (3), and a sterol, ergosta-4,6,8(14),22-tetraen-3-one (4), with stigmasterol, and oleic and linoleic acids, have been isolated from an MeOH extract of the dried bark of Aphanamixis polystachya. The structures of the isolated compounds were elucidated by analysis of 1D and 2D NMR and mass spectroscopic data. The compounds did not have growth inhibitory activity against HeLa cells.     

Antioxidative iridoid glycosides and phenolic compounds from <Emphasis Type="Italic">Veronica peregrina</Emphasis>

Eight iridoid glycosides and four phenolic compounds were isolated from the EtOAc soluble fraction of Veronica peregrina MeOH extract as the radical scavengers for antioxidant activity. The compounds were identified as protocatechuic acid (1), luteolin (2), veronicoside (3), minecoside (4), specioside (5), amphicoside (6), catalposide (7), 6-O-cis-p-coumaroyl catalpol (8), p-hydroxy benzoic acid methyl ester (9), verproside (10), verminoside (11), and chrysoeriol 7-glucuronide (12) by spectroscopic analysis. All compounds except for 1 and 2 were isolated for the first time from this plant. The antioxidant activity was evaluated by the ORAC(Oxygen Radical Absorbance Capacity) assay, which measures scavenging activity against peroxy radicals induced by 2,2′-azobis (2-methoxypropion-amidine) dihydrochloride, and the ORAC value is expressed as relative trolox equivalent. Compounds 2, 4, 5, 6, 8, and 12 exhibited potent antioxidant activity, and compounds 1, 11 had similar activity with trolox, whereas the other compounds showed weaker activity than trolox.     

Norlignan derivatives from <Emphasis Type="Italic">Curculigo crassifolia</Emphasis> and their DPPH radical scavenging activity

A novel norlignan derivative, crassifogenin C (1), and a known compound, curcapital (2), were isolated from the ethanolic extract of the rhizomes of Curculigo crassifolia. Their structures were elucidated on the basis of spectroscopic evidence and comparisons with literature data. Curcapital (2) was isolated from this plant for the first time. The free radical scavenging activity of the isolated compounds along with crassifoside E (3) and crassifoside F (4), which were reported previously, was evaluated by the 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. All compounds showed strong radical scavenging activity. The primary structure-activity relationship is also discussed.     

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.     

Phenolic constituents of <Emphasis Type="Italic">Acorus gramineus</Emphasis>

The purification of a MeOH extract from the rhizome of Acorus gramineus (Araceae) using column chromatography furnished two new stereoisomers of phenylpropanoid, acoraminol A (1) and acoraimol B (2). It also furnished 17 known phenolic compounds, β-asarone (3), asaraldehyde (4), isoacoramone (5), propioveratrone (6), (1′R,2′S)-1′,2′-dihydroxyasarone (7), (1′S,2′S)-1′,2′-dihydroxyasarone (8), 3′,4′-dimethoxycinnamyl alcohol (9), 3′,4′,5′-trimethoxycinnamyl alcohol (10), kaempferol 3-methyl ether (11), 2-[4-(3-hydroxypropyl)-2-methoxyphenoxy]-1,3-propanediol (12), hydroxytyrosol (13), tyrosol (14), (2S,5S)-diveratryl-(3R,4S)-dimethyltetrahydrofuran (15), (7S,8R)-dihydrodehydrodiconiferyl alcohol (16), 7S,8S-threo-4,7,9,9′-tetrahydroxy-3,3′-dimethoxy-8-O-4′-neolignan (17), 7S,8R-erythro-4,7,9,9′-tetrahydroxy-3,3′-dimethoxy-8-O-4′-neolignan (18), and dihydroyashsbushiketol (19). The structures of the new compounds were elucidated by analysis of spectroscopic data including 1D and 2D NMR data. The absolute configurations of 1 and 2 were determined using the convenient Mosher ester procedure. Compounds 5–19 were isolated for the first time from this plant source. The isolated compounds were tested for cytotoxicity against four human tumor cell lines in vitro using a Sulforhodamine B (SRB) bioassay.     

Assessment of the antibacterial activity of phenylethanoid glycosides from <Emphasis Type="Italic">Phlomis lanceolata</Emphasis> against multiple-drug-resistant strains of <Emphasis Type="Italic">Staphylococcus aureus</Emphasis>

Three phenylethanoid glycosides, forsythoside B (1), phlinoside C (2) and verbascoside (3), were isolated from the methanol extract of the leaves of Phlomis lanceolata, an Iranian medicinal plant, by reversed-phase preparative high-performance liquid chromatography (HPLC), and the structures of these compounds were elucidated conclusively by ultraviolet (UV), mass spectrometry (MS) and a series of 1D and 2D nuclear magnetic resonance (NMR) analyses. The antibacterial properties of 1–3 against five multi-drug-resistant (MDR) strains of Staphylococcus aureus have been assessed by the rapid and robust microtitre-plate-based serial dilution method. While compounds 1 and 3 showed considerable activities against all five strains, compound 2 was inactive at the test concentrations.     

Biologically active <Emphasis Type="Italic">C</Emphasis>-alkylated flavonoids from <Emphasis Type="Italic">Dodonaea viscosa</Emphasis>

A new C-alkylated flavonoid (5,7-dihydroxy-3′-(4″-acetoxy-3″-methylbutyl)-3,6,4′-trimethoxyflavone (1), along with two known C-alkylated flavonoids (5,7-dihydroxy-3′-(3-hydroxymethylbutyl)-3,6,4′-trimethoxyflavone (2), 5,7,4′-trihydroxy-3′-(3-hyroxymethylbutyl)-3,6-dimethoxyflavone (3) and two new source C-alkylated flavonoids (5,7-dihydroxy-3′-(2-hydroxy-3-methyl-3-butenyl)-3,6,4′-trimethoxyflavone (4), 5,7,4′-trihydroxy-3,6-dimethoxy-3′-isoprenyl-flavone (5) were isolated from the aerial parts of Dodonaea viscosa. The structures of all compounds were established on the basis of 1D and 2D NMR spectroscopy and mass spectrometry. The isolated compounds were evaluated for their inhibitory effect on urease and α-chymotrypsin enzyme. All the compounds (1–5) exhibited mild inhibition against urease but remained recessive in case of α-chymotrypsin.     

Constituents of the stems and fruits of<Emphasis Type="Italic">Opuntia ficus-indica</Emphasis> var.<Emphasis Type="Italic">saboten</Emphasis>

From the stems and fruits of Opuntia ficus-indica var. saboten, eight flavonoids, kaempferol (1), quercetin (2), kaempferol 3-methyl ether (3), quercetin 3-methyl ether (4), narcissin (5), (+)-dihydrokaempferol (aromadendrin, 6), (+)-dihydroquercetin (taxifolin, 7), eriodictyol (8), and two terpenoids, (6S,9S)-3-oxo-alpha-ionol-beta-D-glucopyranoside (9) and corchoionoside C (10) were isolated and identified by means of chemical and spectroscopic. Among these isolates, compounds 3-5 and 8-10 were reported for the first time from the stems and fruits of O. ficus-indica var. saboten.     

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.     

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 flavonol glycoside from <Emphasis Type="Italic">Hylomecon vernalis</Emphasis>

Purification of a MeOH extract from the aerial parts of Hylomecon vernalis Maxim. (Papaveraceae) using column chromatography furnished a new acetylated flavonol glycoside (1), together with twenty known phenolic compounds (2–21). Structural elucidation of 1 was based on 1D- and 2D-NMR spectroscopy data analysis to be quercetin 3-O-[4‴-O-acetyl-α-L-arabinopyranosyl]-(1‴→6″)-β-D-galactopyranoside (1). The structures of compounds 2–21 were elucidated by spectroscopy and confirmed by comparison with reported data; quercetin 3-O-[2‴-O-acetyl-α-L-arabinopyranosyl]-(1‴→6″)-β -D-galactopyranoside (2), quercetin 3-O-α-L-arabinopyranosyl-(1‴→6″)-β-D-galactopyranoside (3), quercetin 3-O-β -D-galactopyranoside (4), kaempferol 3,7-O-α-L-dirhamnopyranoside (5), diosmetin 7-O-β -D-glucopyranoside (6), diosmetin 7-O-β -D-xylopyranosyl-(1‴→6″)-β-D-glucopyranoside (7), p-hydroxybenzoic acid (8), protocatechuic acid (9), caffeic acid (10), 6-hydroxy-3,4-dihydro-1-oxo-β -carboline (11), (Z)-3-hexenyl-β -D-glucopyranoside (12), (E)-2-hexenyl-β -D-glucopyranoside (13), (Z)-3-hexenyl-α-Larabinopyranosyl-(1″→6′)-β-D-glucopyranoside (14), oct-1-en-3-yl-α-L-arabinopyranosyl-(1″→6′)-β-D-glucopyranoside (15), benzyl-β-D-apiofuranosyl-(1″→6′)-β-D-glucopyranoside (16), benzyl-α-L-arabinopyranosyl-(1″→6′)-β-D-glucopyranoside (17), benzyl-β-D-xylopyranosyl-(1″→6′)-β-Dglucopyranoside (18), 2-phenylethyl-α-L-arabinopyranosyl-(1″→6′)-β-D-glucopyranoside (19), 2-phenylethyl-β-D-apiofuranosyl-(1″→6′)-β-D-glucopyranoside (20), and aryl-β-D-glucopyranoside (21). Compounds 2-21 were isolated for the first time from this plant. The isolated compounds were tested for cytotoxicity against four human tumor cell lines in vitro using a Sulforhodamin B bioassay.     

Cytotoxic phenolic compounds from <Emphasis Type="Italic">Chionanthus retusus</Emphasis>

Cytotoxicity-guided fractionation and purification of MeOH extract from Chionanthus retusus Lindl. et Paxton resulted in the isolation of compounds. Fourteen phenolic compounds were isolated from the EtOAc soluble fraction, and their structures were determined by spectroscopic analysis. Isolated compounds were identified as phillygenin (1), scopoletin (2), pinoresinol (3), kaempferol (4), aromadendrin (5), 2-(4-hydroxyphenyl)ethanol (6), 3,3′,5,5′,7-pentahydroxyflavanone (7), luteolin (8), quercetin (9), apigenin (10), chrysoeriol (11), phillyrin (12), oleuropein (13), (7R,8R)-guaiacylglycerol (14). All compounds except for 12 and 13 were isolated for the first time from this plant and genus Chionanthus. Anti-proliferative effect of isolated compounds were evaluated by the sulforhodamin B assay against four human tumor cell lines (A549, SK-OV-3, SK-MEL-2, and HCT15). Compounds 4 and 8–10 were significantly active with ED50 values of 1.84–6.35 μg/mL. Also, compounds 1, 3, 5 and 7 revealed cytotoxic effects at concentrations below 30 μg/mL.     

A new triterpenoid from <Emphasis Type="Italic">Brucea javanica</Emphasis>

A new triterpenoid, bruceajavanin C (1), together with bruceosides A and B (2 and 3), bruceines D and E (4 and 5), yadanziosides A and G (6 and 7), (20R)-O-(3)-α-L-arabinopyranosylpregn-5-ene-3β,20-diol (8), and α-D-glucopyranoside, (3β, 20R)-3-hydroxypregn-5-en-20-yl (9) were isolated from the aerial parts of Brucea javanica. The structure of 1 was elucidated on the basis of 2D-NMR spectroscopic analysis. In addition, compounds 1, 3, 4, 5, and 6 exhibited mild inhibitory effect on NO production in LPS-stimulated RAW264.7 cells.     

A new phenylpropane glycoside from the rhizome of <Emphasis Type="Italic">Sparganium stoloniferum</Emphasis>

The purification of the MeOH extract from the rhizome of Sparganium stoloniferum Buch.-Hamil. (Sparganiaceae) using column chromatography furnished one new phenylpropanoid glycoside (7) and known phenolic compounds (1–6, and 8–13). The structural elucidation of 7 was based on 1D- and 2D-NMR spectroscopic data analysis to be β-d-(6-O-trans-feruloyl) fructofuranosyl-α-d-O-glucopyranoside. Compounds 1–6, and 8–13 were elucidated by spectroscopy and confirmed by comparison with reported data; 24-methylenecycloartanol (1), p-hydroxybenzaldehyde (2), ferulic acid (3), p-coumaric acid (4), vanillic acid (5), β-d-(1-O-acetyl-3-O-trans-feruloyl)fructofuranosy-α-d-2′,4′,6′.-O-triacetyglucopyranoisde (6), β-d-(1-O-acetyl-3,6-O-trans-diferuloyl)fructofuranosyl-β-d-2′,4′,6′.-O-triacetylglucopyranoisde (8), hydroxytyrosol acetate (9), hydroxytyrosol (10), isorhamnetin-3-O-rutinoside (11), n-butyl-α-d-fructofuranoside (12), and n-butyl-β-d-fructopyranoside (13). Compounds 3 and 9–13 were isolated for the first time from this plant. The isolated compounds were tested for cytotoxicity against four human tumor cell lines in vitro using a Sulforhodamin B bioassay.     

Potential anthelmintics: polyphenols from the tea plant <Emphasis Type="Italic">Camellia sinensis</Emphasis> L. are lethally toxic to <Emphasis Type="Italic">Caenorhabditis elegans</Emphasis>

A novel gallate of tannin, (−)-epigallocatechin-(2β→O→7′,4β→8′)-epicatechin-3′-O-gallate (8), together with (−)-epicatechin-3-O-gallate (4), (−)-epigallocatechin (5), (−)-epigallocatechin-3-O-gallate (6), and (+)-gallocatechin-(4α→8′)-epigallocatechin (7), were isolated from the tea plant Camellia sinensis (L.) O. Kuntze var. sinensis (cv., Yabukita). The structure of 8, including stereochemistry, was elucidated by spectroscopic methods and hydrolysis. The compounds, along with commercially available pyrogallol (1), (+)-catechin (2), and (−)-epicatechin (3), were examined for toxicity towards egg-bearing adults of Caenorhabditis elegans. The anthelmintic mebendazole (9) was used as a positive control. Neither 2 nor 3 were toxic but the other compounds were toxic in the descending order 8, 7 ≈ 6, 9, 4, 5, 1. The LC₅₀ (96 h) values of 8 and 9 were evaluated as 49 and 334 μmol L⁻¹, respectively. These data show that many green tea polyphenols may be potential anthelmintics.     

Antibacterial activity of <Emphasis Type="Italic">Capsicum annuum</Emphasis> extract and synthetic capsaicinoid derivatives against <Emphasis Type="Italic">Streptococcus mutans</Emphasis>

The inhibitory effects of the ethyl acetate extract and capsaicin (1) and dihydrocapsaicin (2) isolated from fruits of Capsicum annuum chili pepper type, and synthetic capsaicinoid derivatives (N-(4-hydroxyphenylethyl)decamide (3), (E)-N-(4-hydroxy-3-methoxybenzyl)-3,7-dimethylocta-2,6-dienamide (4), 4-hydroxy-3-methoxy-N-((E)-3,7-dimethylocta-2,6-dienyl)benzamide (5) and N-(4-hydroxy-3-methoxybenzyl)decamide (6) at different concentrations were evaluated against Streptococcus mutans. The minimum inhibitory concentration at which the ethyl acetate extract prevented the growth of S. mutans was 2.5 mg/mL; those of the isolated compounds 1 and 2 were 1.25 μg/mL, while 3 was 5.0 μg/mL, and 4, 5 and 6 were 2.5 μg/mL, respectively.