Aporphine alkaloids from <Emphasis Type="Italic">Clematis parviloba</Emphasis> and their antifungal activity

A new aporphine alkaloid, β-magnoflorine (1), together with a known aporphine alkaloid, α-magnoflorine (2), were isolated from the aerial parts of Clematis parviloba. Their structures were elucidated on the basis of comprehensive spectroscopic techniques. In addition, both compounds showed potent antifungal activities against Penicillium avellaneum UC-4376.     

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.     

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.     

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.     

Oligostilbenoids from <Emphasis Type="Italic">Shorea gibbosa</Emphasis> and their cytotoxic properties against P-388 cells

A new oligostilbenoid derivative, diptoindonesin F (1), along with five known oligostilbenoids, (−)-ampelopsin A (2), (−)-α-viniferin (3), ampelopsin E (4), (−)-vaticanol B (5), and (−)-hemsleyanol D (6), were isolated from the methanol extract of the tree bark of Shorea gibbosa. The structure of the new compound was determined based on the analysis of spectroscopic data, including UV, IR, NMR 1-D and 2-D, and mass spectra. Cytotoxic properties of the isolated oligostilbenoids were evaluated against murine leukemia P-388 cells with the result that compounds 2 and 4 showed the highest cytotoxicity.     

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.     

A new erythrinan alkaloid from the seed of <Emphasis Type="Italic">Erythrina addisoniae</Emphasis>

Phytochemical study on the EtOAc extract of the seed of Erythrina addisoniae (Leguminosae) resulted in the isolation of a new erythrinan alkaloid, erysovine-N-oxide (1), along with eight known alkaloids, erysosalvinone (2), erysodine (3), 1H-indole-3-propanamide (4), glucoerysodine (5), erysotrine (6), erysovine (7), erythraline (8) and erysopine (9). Their chemical structures were identified on the basis of physicochemical and spectroscopic analyses.     

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.     

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.     

Chemical and biologically active constituents of <Emphasis Type="Italic">Pteris multifida</Emphasis>

A new compound, 4-caffeoyl quinic acid 5-O-methyl ether (2), together with 12 known compounds—identified as (2R,3R)-pterosin L 3-O-β-d-glucopyrannoside (3), β-sitosterol β-d-glucopyranoside (4), apigenin 7-Ο-β-d-glucopyranoside (5), luteolin 7-Ο-β-d-glucopyranoside (6), sucrose (7), caffeic acid (8), pterosin C 3-Ο-β-d-glucopyranoside (9), pteroside C (10), 4,5-dicaffeoyl quinic acid (11), pteroside A (12), wallichoside (13) and (2S)-5,7,3′,5′-tetrahydroxyflavanone (14)—were isolated from Pteris multifida. The structure of the new compound was determined by means of physical, chemical and spectroscopic evidence. Compounds 5 and 6 were the main constituents of the plant, with yields of 0.19% and 0.16%, respectively. The cytotoxic activities of 2, 3, and 9–13 were evaluated against a human cell line (KB cells). Among the isolated compounds, pterosin C 3-Ο-β-d-glucopyrannoside (9) and 4,5-dicaffeoylquinic acid (11) showed a significant selective cytotoxicity (IC₅₀ 2.35 and 5.38, respectively), while moderate activity was observed for compound 2 (IC₅₀ 12.3). The chemosystematics of Pteris species is also discussed.     

A new furofuran lignan from <Emphasis Type="Italic">Isodon japonicus</Emphasis>

A new sesamin type furofuran lignan, (−)-sesamin-2,2′-diol (1), along with two known flavonoids (2 and 3) and three phenolic compounds (4–6) were isolated from the aerial parts of Isodon japonicus. The structures of these compounds were determined by analysis of spectroscopic data (1D-, 2D-NMR, HRMS and CD) and by comparison of the data with those of related metabolites.     

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.     

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.     

A new amide from the leaves and twigs of <Emphasis Type="Italic">Litsea auriculata</Emphasis>

A new amide, N-trans-sinapoylmethoxytyramine (1), along with three known amides (2–4) and two known flavonol 3-O-rhamnosides (5 and 6), were isolated from the leaves and twigs of Litsea auriculata. The structures of the isolated compounds (1–6) were characterized on the basis of spectroscopic analyses, and their cytotoxic activity against HeLa cells was estimated.     

Tropane alkaloids from <Emphasis Type="Italic">Erythroxylum emarginatum</Emphasis>

A tropane alkaloid, anhydroecgonine methyl ester N-oxide (2), was isolated for the first time as a naturally occurring compound, with anhydroecgonine methyl ester (1) from the bark of Erythroxylum emarginatum. Compound 1 was also isolated from the twigs. Their structures were elucidated mainly by spectroscopic methods.     

Prenylated flavones from <Emphasis Type="Italic">Artocarpus altilis</Emphasis>

Six prenylated flavones, including one new compound, were isolated and identified from the stem bark extracts of Artocarpus altilis. The new prenylated flavone hydroxyartocarpin (1) was characterized as 3-(γ,γ-dimethylallyl)-6-isopentenyl-5,8,2′,4′-tetrahydroxy-7-methoxyflavone and the known compounds were artocarpin (2), morusin (3), cycloartobiloxanthone (4), cycloartocarpin A (5) and artoindonesianin V (6). The structures of the compounds were determined by spectroscopic methods (IR, MS, ¹H-NMR and ¹³C-NMR) and comparison with published data for the known compounds.     

New alkaloid from the aerial parts of <Emphasis Type="Italic">Codonopsis clematidea</Emphasis>

A new codonopsine-related alkaloid and 13 known compounds were isolated from the aerial parts of Codonopsis clematidea (Campanulaceae). The structure of the new compound was elucidated by two-dimensional nuclear magnetic resonance and other spectral examinations.     

An oxepinoflavone from <Emphasis Type="Italic">Artocarpus elasticus</Emphasis> with cytotoxic activity against P-388 cells

A new oxepinoflavone, artoindonesianin E1 (1), was isolated from the wood of Artocarpus elasticus, along with four known prenylated flavones: artocarpin (2), cycloartocarpin (3), cudraflavones A (4) and C (5). The structure of the new compound was identified by spectroscopic methods. Upon cytotoxic evaluation against murine leukemia P-388 cells, the new compound showed IC₅₀ 5.0 μg/mL.     

A new lignan glucoside from the stems of <Emphasis Type="Italic">Callicarpa japonica</Emphasis> Thunb. var. <Emphasis Type="Italic">luxurians</Emphasis> Rehd.

A new lignan glucoside (1) was isolated from the stems of Callicarpa japonica Thunb. var. luxurians Rehd. (Verbenaceae), along with six known lignan glucosides and three known triterpenoids. The chemical structure of 1 was characterized as (+)-lyoniresinol 3α-O-(6″-3,5-dimethoxy-4-hydroxybenzoyl)-β-d-glucopyranoside on the basis of spectroscopic data. In addition, the radical-scavenging effect of four lignans on the stable free radical 1,1-diphenyl-2-picrylhydrazyl was examined. Among the tested compounds, three compounds, including 1, showed almost the same scavenging activity as that of α-tocopherol.