New prenylated flavones from <Emphasis Type="Italic">Artocarpus champeden</Emphasis>, and their antimalarial activity in vitro

Two new prenylated flavones, artocarpones A and B (1 and 2), and seven known isoprenylated flavonoids, artonin A (3), cycloheterophyllin (4), artoindonesianin E (5), artoindonesianin R (6), heterophyllin (7), heteroflavanone C (8), and artoindonesianin A-2 (9), have been isolated from the stem bark of Artocarpus champeden. Their structures were determined by spectroscopic analysis. Among the compounds isolated, 8 had the most potent inhibitory activity against the growth of Plasmodium falciparum 3D7 clone, with an IC₅₀ value of 1 nmol L⁻¹.     

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.     

Constituents of the roots of <Emphasis Type="Italic">Ligularia dentata</Emphasis> Hara

Nine known compounds, butyrospermol (1), lupeol (2), stigmast-4-en-3-one (3), stigmast-4-ene-3,6-dione (4), (+)-methyl abscisate (5), methyl indole-3-carboxylate (6), vanillin (7), methyl (E)-caffeate (8), and methyl (E)-ferulate (9), and two new compounds, methyl (E)-feruloylglycolate (10), and methyl-7,8-dihydro-(S)-7-methoxyferulate (11), have been isolated from the roots of Ligularia dentata Hara (Compositae). The structures were elucidated on the basis of spectral data.     

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.     

Prenylated xanthones from <Emphasis Type="Italic">Hypericum ascyron</Emphasis>

Three new prenylated xanthones, 1,3,5-trihydroxy-6,7-[2′-(1-methylethenyl)-dihydrofurano]-xanthone (1), 1,3,5-trihydroxy-6,7-[2′-(1-hydroxy-1-methylethyl)-dihydrofurano]-xanthone (2), and 1,3,5-trihydroxy-6-O-prenyl-xanthone (3), together with eight known compounds were isolated from the leaves of Hypericum ascyron. Compound 3 has an O-prenyl moiety, and therefore represents the first reported xanthone to have an O-prenyl moiety from genus Hypericum. The structures of the isolated compounds were established based on spectroscopic data and on a comparison with values for previously identified analogues.     

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 kaempferol trioside from <Emphasis Type="Italic">Solidago altissima</Emphasis> L.

A new kaempferol trioside [kaempferol 3-O-rutinoside 7-O-β-d-apiofuranoside, (1)] was isolated together with nine phenolic compounds, trans-tiliroside (2), caffeic acid (3), chlorogenic acid (4), 3-O-caffeoylquinic acid (5), 4-O-caffeoylquinic acid (6), 3-O-coumaroylquinic acid (7), 4-O-coumaroylquinic acid (8), 3,5-di-O-caffeoylquinic acid (9) and 4,5-dicaffeoylquinic acid (10) from the leaves of Solidago altissima L. The structure elucidations of the compounds were based on the analyses of spectroscopic data.     

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.     

A new flavonol galloylrhamnoside and a new lignan glucoside from the leaves of <Emphasis Type="Italic">Koelreuteria henryi</Emphasis> Dummer

A new flavonol galloylrhamnoside, kaempferol 3-O-(2″,3″-di-O-galloyl)-α-l-rhamnopyranoside, and a new lignan glycoside, hinokinin 7-O-β-d-glucopyranoside were isolated from the leaves of Koelreuteria henryi, along with 18 known compounds, including six flavonol glycosides (3–8), three lignans (9–11), four chlorophyll derivatives (12–15), two steroids (16, 17), and three aromatic compounds (18–20). The structures were determined on the basis of spectral analysis and chemical evidence. The scavenging effect of 1–8 and 20 on the stable free radical 1,1-diphenyl-2-picrylhydrazyl was examined. Compounds 1, 5, 6, and 20 showed more potent activity than that of trolox.     

Chemical constituents of <Emphasis Type="Italic">Polyalthia parviflora</Emphasis> stem

From the stem of Polyalthia parviflora, four compounds were isolated, including p-hydroxyphenylethyl p-coumarate (1), p-hydroxyphenylethyl ferulate (2), dehydrodiscretamine (3) and (−)-discretamine (4). Complete ¹H and ¹³C NMR assignments were obtained for 1, 3 and 4 for the first time.     

Two new lignan glucosides from the fruit of <Emphasis Type="Italic">Vitex cannabifolia</Emphasis>

Two new phenyldihydronaphthalene-type lignan glucosides, vitecannasides A (1) and B (2) were isolated from the fruit of Vitex cannabifolia Sieb. et. Zucc. (Verbenaceae) along with the six known lignan derivatives (3–8), four known iridoid glucosides (9–12), three known flavonoids (13–15), and one known phenylbutanone glucoside (16). Their chemical structures were determined on the basis of spectroscopic data as well as chemical evidence. The scavenging effect of 1, 2, and 11–16 on the stable free radical 1,1-diphenyl-2-picrylhydrazyl was examined. Compounds 1, 2, 14, and 15 exhibited stronger activity than that of l-cysteine. Especially, 14 and 15 showed more potent activity than that of α-tocopherol.     

A new phenylethanoid glycoside from the fruits of <Emphasis Type="Italic">Callicarpa japonica</Emphasis> Thunb. var. <Emphasis Type="Italic">luxurians</Emphasis> Rehd.

A new phenylethanoid glycoside, named acetyl forsythoside B (1), was isolated from the fruits of Callicarpa japonica Thunb. var. luxurians Rehd. (Verbenaceae) along with forsythoside B (2), brandioside (3), poliumoside (4), actioside (5), and apigenin 7-galacturonide (6). The structures of 1–6 were determined on the basis of spectroscopic data. In addition, the antioxidative activity of 1–4 and 6 was evaluated by the ferric thiocyanate method. All of the tested compounds except 6 exhibited almost the same activity as 3-tert-butyl-4-hydroxyanisole. The radical-scavenging effect of 1–6 on the stable free radical 1,1-diphenyl-2-picrylhydrazyl was also examined. Compounds 1–5 showed almost twice the activity compared to α-tocopherol.     

Secoiridoid glycosides from the leaves of <Emphasis Type="Italic">Hydrangea macrophylla</Emphasis> subsp. <Emphasis Type="Italic">serrata</Emphasis>

Seven secoiridoid glycosides, secologanin dimethyl acetal (1), n-butyl vogeloside (2), n-butyl epi-vogeloside (3), (7R)-n-butyl morroniside (4), hydrangenoside A (5), hydrangenoside C (6), and hydrangenoside A dimethyl acetal (7), have been isolated from the leaves of Hydrangea macrophylla subsp. serrata (Thunb.) Makino (Saxifragaceae). The structures were elucidated on the basis of spectral data.     

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.     

Studies of the chemical constituents of the flower buds of <Emphasis Type="Italic">Magnolia kobus</Emphasis> and <Emphasis Type="Italic">M. salicifolia</Emphasis>

The constituents of the flower buds of Magnolia kobus DC. and M. salicifolia MAXIM. have been investigated. We isolated and identified six bis-tetrahydrofuran-type and three tetrahydrofuran-type lignan derivatives from M. kobus, and one bis-tetrahydrofuran-type lignan and eight phenylpropanoid-type derivatives from M. salicifolia. The structures of these compounds were elucidated on the basis of chemical and spectroscopic evidence.     

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.     

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.     

Three new lignan glycosides from Mananthes patentiflora

Three new lignan glycosides, mananthosides I–K (1–3), were isolated from the ethanolic extract of the aerial part of Mananthes patentiflora. The structure elucidation of these compounds was mainly established on the basis of 1D NMR, 2D NMR and HR-MS spectroscopic analysis.     

New phenylpropanoid esters of sucrose from <Emphasis Type="Italic">Polygonum hydropiper</Emphasis> and their antioxidant activity

By various chromatographic methods, two new phenylpropanoid esters of sucrose named hidropiperosides A (1) and B (2), and three known compounds as vanicosides A (3), B (4), and E (5) were isolated from the methanolic extract of the whole plant of Polygonum hydropiper L. (Polygonaceae). Their structures were elucidated by extensive spectroscopic methods including 1D-and 2D-NMR experiments, as well as ESI-MS analysis. All the isolated compounds were tested for their antioxidant activity in the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay system. Among them, compounds 2 and 3 showed significant antioxidant activity with their SC₅₀ values of 23.4 and 26.7 μg/mL, respectively.