Chemical constituents from the whole herbs of Peperomia tetraphylla and their chemotaxonomic significance

Our studies report the isolation of seventeen compounds (1–17), which include three phenolic acids (12–14), seven flavonoids (3, 6, 8, 11, 15–17), four secolignans (1, 2, 5 and 9), one tetrahydrofuran lignin (10) and two alkaloids (4 and 7). These compounds have been obtained from the Peperomia tetraphylla using chromatographic methods. Their structures were confirmed based on spectroscopic methods. Among them, five compounds (4, 7, 8, 11 and 15) were found in the family, four compounds (3 and 12–14) were firstly reported from genus Peperomia, and four compounds (6, 9, 16 and 17) were firstly obtained from this species. Furthermore, the chemotaxonomic significance of these ingredients from the whole plants of P. tetraphylla has been discussed in detail.     

Three New Phenolic Amides from the Roots of Eggplant (Solanum melongena L.)

The isolation of four phenolic amides, four phenolic compounds and an aromatic amine from the roots of eggplant is described. The phenolic amides were identified as N-trans-feruloyl tyramine (V), N-trans-p-coumaroyl tyramine (VII), N-trans-feruloyl octopamine (VIII) and N-trans-p-coymaroyl octopamine (IX). The three amides V, VIII and IX are new compounds. Furthermore, four phenolic compounds were identified as vanillin (I), isoscopoletin (II), ethyl caffeate (IV) and ferulic acid (VI). The aromatic amine was identified as p-aminobenzal-dehyde (III).     

Bio-assay guided isolation and identification of α-glucosidase inhibitors from the leaves of Aquilaria sinensis

Eight α-glucosidase inhibitors including four new compounds were isolated from the 70% aqueous ethanolic extract of leaves of Aquilaria sinensis (Lour.) Gilg by activity-directed fractionation and purification processes. The ethanolic extract was first separated into petroleum ether, ethyl acetate, n-butanol and water soluble fractions and screened for inhibitory activity against α-glucosidase. Further activity-directed investigation lead to the isolation of four new compounds with moderate inhibitory activity, viz, aquilarisinin (1), aquilarisin (2), hypolaetin 5-O-β-D-glucuronopyranoside (3) and aquilarixanthone (4) from the n-butanol fraction, and four known compounds showing potent activity including mangiferin (5), iriflophenone 2-O-α-L-rhamnopyranoside (6), iriflophenone 3-C-β-D-glucoside (7) and iriflophenone 3,5-C-β-D-diglucopyranoside (8) from the most potent ethyl acetate fraction. The structures of these compounds were determined by extensive spectroscopic analyses, including IR, UV, ESIMS, HRESIMS, 1D and 2D NMR.     

Antifungal bis[bibenzyls] from the Chinese liverwort Marchantia polymorpha L

Bioassay-guided separation of the antifungal constituents of the Chinese liverwort Marchantia polymorpha L. (Marchantiaceae) led to the isolation of seven bis[bibenzyl]-type macrocycles. On the basis of NMR and MS analyses, the three new compounds plagiochin E (1), 13,13'-O-isoproylidenericcardin D (4), and riccardin H (7) were identified, together with four known compounds: marchantin E (2), neomarchantin A (3), marchantin A (5), and marchantin B (6). Their antifungal activities against Candida albicans were determined by TLC bioautography.     

马尾松松针中化学成分的分离与鉴定

利用Diaion HP-20、Toyopearl HW-40及硅胶柱色谱进行分离纯化,研究松科(Pinaceae)植物马尾松(Pinus,massoniana Lamb．)松针的化学成分。从马尾松松针水煎液的正丁醇部位分离得到了4个化合物,根据理化性质和光谱数据分别鉴定为：(7S,8R)-4,9′-二羟基-3,3′-二甲氧基-7,8-二氢苯并呋喃-1′-丙基新木脂素-9-O-β-D-吡喃葡萄糖苷(1),对羟基苯基-2-丁酮(2),香草酸(3),氢醌(4)。这4个化合物均为首次从本植物中分离得到。     

Diosgenin glucuronides from Solanum lyratum and their cytotoxicity against tumor cell lines

Bioassay-directed fractionation of the cytotoxicity active fraction of the whole plant from Solanum lyratum led to the isolation of a new steroidal saponin, diosgenin 3-O-beta-D-glucopyranosiduronic acid methyl ester (2), as well as four known compounds, diosgenin (1), diosgenin 3-O-beta-D-glucopyranosiduronic acid (3), diosgenin 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucopyranosiduronic acid (4), diosgenin 3-O-alpha-L-rhamnopyranosyl-(1-->2)-beta-D-glucuroniduronic acid methyl ester (5). The structures of the isolated compounds were elucidated on the basis of their spectral data and chemical evidences. Compound 1 was isolated for the first time from this plant, and compound 3 was isolated as a new natural product. Cytotoxic activities of the isolated compounds were evaluated and the cytotoxicities of compounds 2-5 reported for the first time.     

Constituents of Asarum sieboldii with inhibitory activity on lipopolysaccharide (LPS)-induced NO production in BV-2 microglial cells

Bioassay-guided fractionation of the root extract of Asarum sieboldii led to the isolation of the four active compounds (-)-sesamin (1), (2E,4E,8Z,10E)-N-(2-methylpropyl)dodeca-2,4,8,10-tetraenamide (2), kakuol (3), and '3,4,5-trimethoxytoluene' (=1,2,3-trimethoxy-5-methylbenzene; 4), in terms of inhibition of lipopolysaccharide (LPS)-induced nitric oxide (NO) production. Compounds 1-4 showed potent inhibition of NO production, with IC(50) values in the low nanomolar-to-micromolar range. Also isolated were the known compounds methylkakuol (5), '3,5-dimethoxytoluene', safrole, asaricin, methyleugenol, and (-)-asarinin, which were found to be inactive in the above assay. Among the ten known isolates, compounds 1, 2, and 5 were found for the first time in this plant.     

Phytochemical and pharmacological analysis of Bauhinia microstachya (Raddi) Macbr. (Leguminosae)

This paper describes the isolation of four phytoconstituents from the leaves of Bauhinia microstachya, a Brazilian medicinal plant used in folk medicine for the treatment of several ailments. Based on spectroscopic evidence, these compounds were identified as methyl gallate (1), kaempferol 3-O-rhamnosyl (2), quercitrin (3) and myricitrin (4). The crude methanolic extract and two compounds (3 and 4) were tested as analgesic using the writhing test in mice. The extract and compound 3 caused potent and dose-related analgesic effects, confirming the popular use of this plant for the treatment dolorous processes.     

Isoflavones and pterocarpans from Caragana changduensis

Phytochemical investigation of the heartwoods of the stems of Caragana changduensis Lion f. led to the isolation and characterization of six isoflavones (1–6), four pterocarpans (7–10), three lignans (13–15), one chalcone (11), and one isoflavan (12). Among them, compounds 3, 5, 9, 10 and 12–14 were firstly obtained from genus Caragana. The chemotaxonomic significance of these compounds was summarized.     

New lupane triterpenoids from Solidago canadensis that inhibit the lyase activity of DNA polymerase beta

Bioassay-directed fractionation of a methyl ethyl ketone extract of Solidago canadensis L. (Asteraceae), using an assay to detect the lyase activity of DNA polymerase beta, resulted in the isolation of the four new lupane triterpenoids 1-4 and the seven known compounds lupeol, lupeyl acetate, ursolic acid, cycloartenol, cycloartenyl palmitate, alpha-amyrin acetate, and stigmasterol. The structures of the new compounds were established as 3beta-(3R-acetoxyhexadecanoyloxy)-lup-20(29)-ene (1), 3beta-(3-ketohexadecanoyloxy)-lup-20(29)-ene (2), 3beta-(3R-acetoxyhexadecanoyloxy)-29-nor-lupan-20-one (3), and 3beta-(3-hetohexadecanoyloxy)-29-nor-lupan-20-one (4), respectively, on the basis of extensive 1D and 2D NMR spectroscopic interpretation and chemical modification studies. All 11 compounds were inhibitory to the lyase activity of DNA polymerase beta.     

Tigliane diterpene esters with IFN γ-inducing activity from the leaves of Aleurites fordii

Bioactivity-guided fractionation on the leaves of Aleurites fordii led to the isolation of a new tigliane diterpene ester, 12-O-hexadecanoyl-7-oxo-5-ene-16-hydroxyphorbol-13-acetate (1) along with four known compounds, 12-O-hexadecanoyl-7-oxo-5-ene-phorbol-13-acetate (2), 12-O-hexadecanoyl-phorbol-13-acetate (3), 12-O-hexadecanoyl-16-hydroxyphorbol-13-acetate (4), and 12-O-hexadecanoyl-4-deoxy-4α-16-hydroxyphorbol-13-acetate (5). The structures of these compounds were determined by interpretation of NMR (1D and 2D) spectroscopic data and MS data. All the isolates were evaluated for their effects on the induction of IFN-γ in NK92 cells. Compounds 3 and 4 exhibited the most potent responses in IFN-γ induction, comparable to the positive control, phorbol 12-myristate 13-acetate (PMA).     

Acylated quercetagetin glycosides with antioxidant activity from Tagetes maxima

The fractionation of a methanolic extract of Tagetes maxima guided for antioxidant activity resulted in the isolation of three acylated quercetagetin glycosides, quercetagetin-7-O-(6-O-caffeoyl-beta-D-glucopyranoside), quercetagetin-7-O-(6-O-p-coumaroyl-beta-D-glucopyranoside) and quercetagetin-7-O-(6-O-galloyl-beta-D-glucopyranoside), as well as four known flavonoid glycosides. The structural elucidation was accomplished by spectroscopic methods (ESI-MS/MS and NMR). The antioxidant activity of fractions and isolated compounds was determined by checking the scavenging activity against three different radicals: 2,2-diphenyl-1-picrylhydrazyl free radical (DPPH*), hydroxyl (*OH), and superoxide (O2*-). The three isolated compounds exhibited a high radical scavenging activity in comparison with reference compounds.     

5,8-Epidioxysterols and related derivatives from a Chinese soft coral Sinularia flexibilis

Chromatographic separation of the methanolic extract of the marine soft coral, Sinularia flexibilis, resulted in the isolation and characterization of four new sterols, 5alpha,8alpha-epidioxygorgosta-6-en-3beta-ol (1), 5alpha,8alpha-epidioxygorgosta-6,9(11)-dien-3beta-ol (2), 22alpha,28-epidioxycholesta-5,23(E)-dien-3beta-ol (3) and its C-22 epimer (4), along with nine known sterols. The structures of the new compounds were determined on the basis of extensive spectroscopic data (IR, MS, 1H and 13C NMR, HMQC, HMBC, and NOESY) analyses.     

Isolation and structure elucidation of three neo-clerodane diterpenes from Teucrium fruticans L. (LABIATAE)

Recently, the isolation from Teucrium fruticans of neo-clerodanes, namely 7beta-hydroxyfruticolone, 11-hydroxyfruticolone, deacetylfruticolone and 6-acetyl-10-hydroxyteucjaponin B, in addition to fruticolone, isofruticolone and 8beta-hydroxyfruticolone (three out of the four previously reported ones), and 6-acetylteucjaponin B (isolated from T. scordium and T. grisebachii) was reported. Minor compounds presumably of neo-clerodane nature were shown by HPLC analysis on a new extract. Three new compounds, difuranofruticol, deoxyfruticolone and 10-hydroxyteucjaponin B, and the known 7,8-didehydrofruticolone were unambiguously elucidated based on extensive NMR spectral studies (one- and two-dimensional experiments). The compounds were assayed for their antifeedant activity against Spodoptera littoralis and for their antifungal activity against Rhizoctonia solani. Compounds 9-11 showed low antifeedant activity and the feeding ratio of 12 was moderate-low. None of the tested compounds displayed significant activity against R. solani.     

Cytotoxic constituents of Viscum coloratum

Phytochemical studies on Viscum coloratum have resulted in the isolation of nineteen compounds. The structures of the isolated compounds were identified on the basis of 1D, 2D NMR and HR-ESI-Q-TOF-MS. Pachypodol (4) and ombuine (6) were characterized in the family Loranthaceae for the first time. 1,7-Bis(4-hydroxyphenyl)-1,4-heptadien-3-one (8) and 5-hydroxy-3,7,3'-trimethoxyflavone-4'-O-beta-D-glucoside (13) were two new natural compounds, which exhibited cytotoxic activities against four human tumour cell lines (HeLa, SGC-7901, MCF-7, and U251).     

Cytotoxic terpenoids from Juglans sinensis leaves and twigs

Bioassay-guided fractionation of an 80% MeOH extract of Juglan sinensis leaves and twigs has resulted in the isolation of three new triterpenes (1-3) and two new sesquiterpenes (4-5) along with two known sesquiterpenes (6-7). The new compounds were determined to be 3β, 11α, 19α, 24, 30-pentahydroxy-20β, 28-epoxy-28β-methoxy-ursane (1), 1α, 3β-dihydroxy-olean-18-ene (2), 2α, 3α, 23-trihydroxy-urs-12-en-28-oic acid 28-O-β-d-glucopyranoside (3), (4S, 5S, 7R, 8R, 14R)-8, 11-dihydroxy-2, 4-cyclo-eudesmane (4), 15-hydroxy-α-eudesmol-11-O-β-d-glucopyranoside (5), by spectroscopic analysis. The cytotoxicity of compounds (1-7) against four cancer cell lines such as B16F10, Hep-2, MCF-7 and U87-MG was evaluated. Compounds 1, 2, 6 and 7 showed potent cytotoxicity against all of four cancer cell lines, respectively.     

Spirostanol saponins from the rhizomes of Tacca chantrieri and their cytotoxic activity

The rhizomes of Tacca chantrieri have been analysed for steroidal saponin constituents, resulting in the isolation of four new spirostanol saponins (1-4), along with one known saponin (5); their structures were elucidated on the basis of extensive spectroscopic analysis, including 2D NMR, and the results of hydrolytic cleavage. The isolated compounds were evaluated for their cytotoxic activity against HL-60 human promyelocytic leukemia cells.     

Cytotoxic alkaloids from the bulbs of Fritillaria hupehensis

Phytochemical investigation of the bulbs of Fritillaria hupehensis resulted in the isolation and structural elucidation of four new steroidal penta- and hexacyclic veratraman- and cevan-based alkaloids, respectively, compounds 1-4. They were obtained together with the known constituents ebeinine (5) and zhebeinine (6), which were isolated for the first time from this plant. The structures of the new isolates were established by spectroscopic and mass-spectrometric analyses, in combination with chemical methods. All compounds were assayed for their cytotoxic effects towards HeLa and HepG2 cell lines. Compounds 1 and 2 showed significant inhibitory effects against both types of tumor cells, with IC(50) values in the range 2.52-0.23 microM, similar as those for 5-fluorouracil used as positive control.     

Cytotoxic bromoindole derivatives and terpenes from the Philippine marine sponge Smenospongia sp

A detailed chemical analysis of a Philippine marine sponge Smenospongia sp. has been performed. This study yielded four new metabolites, 5-bromo-L-tryptophan (1), 5-bromoabrine (2), 5,6-dibromoabrine (3) and 5-bromoindole-3-acetic acid (4). The pyrroloiminoquinone alkaloid, makaluvamine O (5) as well as 5,6-dibromotryptamine (6), aureol (7) and furospinulosin 1 (8) were also isolated. Although 1 and 4 have been synthesized previously, this is the first report on the isolation of these compounds from a natural source. The furanosesterterpene furospinulosin 1 (8) was obtained for the first time from the genus Smenospongia. The structures of all compounds were established by spectroscopic methods (UV, IR, 1D and 2D NMR, MS, [alpha]D). The cytotoxic potential of 1-8 was evaluated in a panel of isogenic HCT-116 human colon tumor cell lines.     

New Cytotoxic Bibenzyl and Other Constituents from Bauhinia ungulata L. (Fabaceae)

A new bibenzyl, 2′‐hydroxy‐3,5‐dimethoxy‐4‐methylbibenzyl ( 1 ) and four known compounds identified as 2′‐hydroxy‐3,5‐dimethoxybibenzyl ( 2 ), liquiritigenin ( 3 ), guibourtinidol ( 4 ) and fisetinidol ( 5 ) were isolated from the roots of Bauhinia ungulata L. Phytochemical investigations of the stems of B. ungulata led to the isolation of the known compounds identified as liquiritigenin ( 3 ), guibourtinidol ( 4 ), fisetinidol ( 5 ), taraxerol ( 6 ), betulinic acid ( 7 ), taraxerone ( 8 ), glutinol ( 9 ), a mixture of sitosterol ( 10 ) and stigmasterol ( 11 ), pacharin ( 12 ), naringenin ( 13 ) and eriodictyol ( 14 ). The structures of these compounds were elucidated on the basis of their spectral data (IR, MS, 1D‐ and 2D‐NMR). The cytotoxicity of the bibenzyl 1 has been evaluated against four human cancer cell lines, showing the IC₅₀ values of 4.3 and 6.5 μg ml^?1 against pro‐myelocytic leukemia (HL‐60) and cervical adenocarcinoma (HEP‐2) cell lines, respectively. This article also registers for the first time the ¹³C‐NMR data of the known bibenzyl 2 .