C-glycosylflavones from the leaves of Iris tectorum Maxim.

A new C-glycosylflavone, 5-hydroxyl-4′,7-dimethoxyflavone-6-C-[O-(α-l-3′′′-acetylrhamnopyranosyl)-1→2-β-d-glucopyranoside] (1), along with five known C-glycosylflavones, 5-hydroxy-4′,7-dimethoxyflavone-6-C-[O-(α-l-2′′′-acetylrhamnopyranosyl)-1→2-β-d-glucopyranoside] (2), embinin (3), embigenin (4), swertisin (5) and swertiajaponin (6) were isolated from the leaves of Iris tectorum Maxim. Their structures were elucidated on the basis of extensive NMR experiments and spectral methods and their cytotoxic activities against A549 (lung cancer) human cell lines were determined.     

Flavonoid glycosides from leaves and straw of Oryza sativa and their effects of cytotoxicity on a macrophage cell line and allelopathic on weed germination

Five new flavonoids namely, 5-hydroxy-6-isoprenyl-7,4′-dimethoxyflavonol-3-O-β-d-arabinofuranoside (1), 5,7-dihydroxy-4′-methoxyflavone-7-O-β-d-arabinopyranosyl-2′′-n-decan-1′′′-oate (2), 3-butanoyl-5,6,8-trihydroxy-7,4′-dimethoxyflavonol--5-O-β-d-glucopyranoside (3), 7, 4′-dimethoxy-5-hydroxyflavone-5-O-α-d-arabinopyranosyl-(2′′?→?1′′′)-O-α-d-arabinopyranoside (4), and 5,6-dihydroxy-7, 4′-dimethoxyflavone-5-O-α-d-glucopyranoside (5), together with two known compounds, were isolated from the methanol extract of Oryza sativa leaves and straw. Their structures of new compounds were elucidated by 1D and 2D NMR spectral methods, viz: COSY, HMBC and HSQC aided by mass techniques and IR spectroscopy. The cytotoxicity of these compounds (1–7) were assessed by using (RAW 264.7) mouse macrophages cell line, and allelopathic effects of compounds (1–7) on the germination characteristics of barnyardgrass (Echinochloa oryzicola) and pigweed (Chenopodium album L.) were also evaluated. The compounds 1, 6 and 7 showed cytotoxicity and compounds 1–7 exhibited significant inhibitory activity on the seed germination of two weed species.     

Four new antioxidant phenylpropanoid glycosides from Microlepia pilosissima

Four new phenylpropanoid glycosides, 9-O-[β-D-glucopyranosyl-(1→2)-α-L-rhamnopyranosyl]-3,4-dimethoxy-cinnamic acid (1), 9-O-[β-D-glucopyranosyl-(1→2)-α-L-rhamnopyranosyl]-4-methoxycinnamic acid (2), 9-O-α-L-rhamnopyranosyl-3,4-dimethoxy-cinnamic acid (3), and 9-O-[6-Oacetyl-β-D-glucopyranosyl]-4-methoxy-cinnamic acid (4), together with three known compounds 9-O-α-L-rhamnopyranosyl-4-hydroxy-cinnamic acid (5), 9-O-β-D-glucopyranosyl-4-methoxycinnamic acid (6), and 9-O-β-D-glucopyranosyl-3,4-dimethoxy-cinnamic acid (7) were isolated from the 70% EtOH extract of the dry fronds of Microlepia pilosissima. Their chemical structures were elucidated by spectroscopic analysis. Moreover, 1 and 2 exhibited comparable scavenging activities with (±)-α-tocopherol against DPPH radicals, while compounds 3–7 displayed moderate antioxidant activities.     

Two new phenylpropane glycosides from <Emphasis Type="Italic">Allium tuberosum</Emphasis> Rottler

A phytochemical investigation of Allium tuberosum Rottler afforded two new phenylpropane glycosides, named tuberonoid A (1) and B (2), along with four known flavonoids, kaempferol 3-O-β-sophoroside (3), 3-O-β-d-(2-O-feruloyl)-glucosyl-7,4′-di-O-β-d-glucosylkaempferol (4), 3-O-β-sophorosyl-7-O-β-d-(2-O-feruloyl)glucosyl kaempferol (5), kaempferol 3,4′-di-O-β-d-glucoside (6). The identification and structural elucidation of the new compounds were carried out based on spectral data analyses (¹H and ¹³C NMR, ¹H–¹H COSY, HMQC) and HR-MS.     

Phytochemical screening and evaluation of the antimicrobial and antioxidant activities of Ferula caspica M. Bieb. extracts

Chloroform, ethyl acetate and methanol extracts from the aerial parts of Ferula caspica M. Bieb. were tested for their antioxidant capacities by CUPRAC, ABTS, FRAP, Folin–Ciocalteu and aluminum chloride methods and for antimicrobial activities by the broth microdilution method. Chloroform and ethyl acetate extracts showed the highest antioxidant capacity and antimicrobial activity. Three known sesquiterpene derivatives; 1-(2′,4′-dihydroxyphenyl)-3,7,11-trimethyl-3-vinyl-6(E),10-dodecadien-1-one (1), 2,3-dihydro-7-hydroxy-2,3-dimethyl-2-[4′,8′-dimethyl-3′,7′-nonadienyl]-furo[3,2,c]coumarin (2), 2,3-dihydro-7-hydroxy-2,3-dimethyl-3-[4′,8′-dimethyl-3′,7′-nonadienyl]-furo[3,2,c]coumarin(3); phenylpropanoid; laserine/2-epilaserine (4/5) and steroid mixtures; stigmasterol and β-sitosterol (6/7) were isolated from chloroform extract; three known flavonoids; kaempferol-3-O-β-glucopyranoside (8), kaempferol-3-O-α-rhamnopyranoside (9), quercetin-3-O-β-glucopyranoside (10), and one benzoic acid derivative; 2,4-dihydroxybenzoic acid (11) were isolated from the ethyl acetate extract. The structures were elucidated by spectroscopic methods.     

PTP1B inhibitors from Ardisia japonica

In bioassay-directed isolation from the whole plant of Ardisia japonica, sixteen known compounds: chrysophanol (1), physcion (2), oleanolic acid (3), euscaphic acid (4), tormentic acid (5), quercetin (6), quercitrin (7), myricitrin (8), kaempferol 3-O-α-l-rhamnopyranoside (9), cyclamiretin A 3-O-α-l-rhamnopyranosyl(1→4)-β-d-glucopyranosyl(1→2)-[β-d-glucopyranosyl(1→4)]-α-l-arabinopyranoside (10), (7E)-9-hydroxymegastigma-4, 7-dien-3-on-9-O-β-d-glucopyranoside (11), bergenin (12), norbergenin (13), rutin (14), kaempferol 3,7-O-α-l-dirhamnopyranoside (15), (?)-epigallacatechin 3-O-gallate (16) were obtained. Compounds 1–5, 9, 11 and 14–16 have not been reported previously from this plant. Among these isolates, 2, 3, 6 and 12 showed moderate bioactivity against PTP1B in vitro with IC₅₀ values of 121.50, 23.90, 28.12 and 157?μM, respectively.     

A new indole glycoside from the seeds of <Emphasis Type="Italic">Raphanus sativus</Emphasis>

A new indole glycoside, β-d-glucopyranosyl 2-(methylthio)-1H-indole-3-carboxylate, named raphanuside A (1), as well as eight known compounds, β-d-fructofuranosyl-(2 → 1)-(6-O-sinapoyl)-α-d-glucopyranoside (2), (3-O-sinapoyl)-β-d-fructofuranosyl-(2 → 1)-α-d-glucopyranoside (3), (3-O-sinapoyl)-β-d-fructofuranosyl-(2 → 1)-(6-O-sinapoyl)-α-d-glucopyranoside (4), (3,4-O-disinapoyl)-β-d-fructofuranosyl-(2 → 1)-(6-O-sinapoyl)-α-d-glucopyranoside (5), isorhamnetin 3,4′-di-O-β-d-glucoside (6), isorhamnetin 3-O-β-d-glucoside-7-O-α-l-rhamnoside (7), isorhamnetin 3-O-β-d-glucoside (8) and 3'-O-methyl-(?)-epicatechin 7-O-β-d-glucoside (9) were isolated from the seeds of Raphanus sativus. Furthermore, compounds 1–3 and 6–9, were isolated from this plant for the first time. The structures of compounds 1–9 were identified using 1D and 2D NMR, including ¹H–¹H COSY, HSQC, HMBC and NOESY spectroscopic analyses. The inhibitory activity of these isolated compounds against interleukin-6 (IL-6) production in TNF-α stimulated MG-63 cells was also examined.     

Raddeanalin,a new flavonoid glycoside from the leaves of Salix raddeana Laksh.

A new flavonoid glycoside, diosmetin 7-O-β-D-xylopyranosyl(1–6)-β-d-glucopyranoside, named raddeanalin (1), was isolated from the ethanolic extract of the leaves of Salix raddeana Laksh. together with three known compounds, kaempferol 3-O-glucoside (2), quercetin 3-O-glucoside (3) and quercetin 3-O-rutinoside (4). The structure of new compound was established by the spectral data and chemical properties.     

A new acylated flavonol glycoside from Derris triofoliata

A new acylated flavonol glycoside, kaempferol 3-O-[(6″″-feruloyl)-β-D-glucopyranosyl-(1 → 3)]-[α-L-rhamnopyranosyl-(1 → 6)]-β-D-glucopyranoside and two known cyclolignan glycosides, (+)-lyoniresinol-3α-O-β-D-glucopyranoside and ( ? )-lyoniresinol-3α-O-β-D-glucopyranoside were isolated from n-BuOH extracts of the aerial parts of Derris triofoliata, their structures were determined from spectroscopic and chemical evidences.     

A novel spinosin derivative from Semen Ziziphi Spinosae

A novel spinosin derivative, 6?-(4?′-O-β-d-glucopyranosyl)-vanilloyl spinosin (1) was isolated from the methanol extract of Semen Ziziphi Spinosae, together with five known flavonoids, swertish (2), spinosin (3), 6?-feruloylspinosin (4), isospinosin (5) and kaempferol 3-O-α-l-rhamnopyranosyl-(1 → 2)-O-[O-α-l-rhamnopyranosyl-(1 → 6)]-β-d-glucopyranoside (6), and two alkanoids, zizyphusine (7) and 6-(2′,3′-dihydroxyl-4′-hydroxymethyl-tetrahydro-furan-1′-yl)-cyclopentene[c]pyrrole-1,3-diol (8). The structure of compound 1 was elucidated by spectroscopic methods including UV, IR, ESI-TOF-MS, 1D, and 2D NMR techniques.     

Triterpene saponins from the leaves of Ilex kudingcha

Three new triterpene saponins, ilekudinosides T–V (1–3), along with six known saponins were isolated from the 70% ethanolic extract of the leaves of Ilex kudingcha. The new saponins were characterized as 3-O-β-d-glucopyranosyl-(1 → 3)-[α-l-rhamnopyranosyl-(1 → 2)]-α-l-arabinopyranosyl-3β,19α-dihydroxy-urs-12(13)-en-28,20β-lactone (1), 3-O-β-d-glucopyranosyl-(1 → 3)-[α-l-rhamnopyranosyl-(1 → 2)]-α-l-arabinopyranosyl-3β,19α-dihydroxy-12-ethoxy-urs-13(18)-ene-28,20β-lactone (2), 3-O-β-d-glucopyranosyl-(1 → 3)-[α-l-rhamnopyranosyl-(1 → 2)]-α-l-arabinopyranosyl-3β,19α-dihydroxy-11-oxo-urs-13(18)-ene-28,20β-lactone (3), respectively. The structures of compounds 1–3 were elucidated on the basis of the chemical and spectroscopic evidence, and the structures of known compounds were identified by comparison of their spectroscopic data with those reported in the literature.     

Two new isoflavone triglycosides from the small branches of Sophora japonica

Two new isoflavone triglycosides, genistein 4′-O-(6″-O-α-l-rhamnopyranosyl)-β-sophoroside (1), and genistein 4′-O-(6?-O-α-l-rhamnopyranosyl)-β-sophoroside (2), together with five known compounds, namely, sophorabioside, genistin, rutin, quercetin 3-O-β-d-glucopyranoside, and kaempferol 3-O-β-d-glucopyranoside, were isolated from the small branches of Sophora japonica L. Their structures were elucidated on the basis of spectroscopic analyses and chemical evidence.     

Three new steroidal saponins from Fritillaria pallidiflora

Three new steroidal saponins, pallidiflosides A (1), B (2), and C (3), have been isolated from the dry bulbs of Fritillaria pallidiflora Schrenk. Their structures were elucidated as 26-O-β-d-glucopyranosyl-(25R)-furost-5,20(22)-dien-3β,26-diol-3-O-β-d-xylopyranosyl(1?→?4)-[α-l-rhamnopyranosyl(1?→?2)]-β-d-glucopyranoside (1); 26-O-β-d-glucopyranosyl-3β,26-dihydroxyl-20,22-seco-25(R)-furost-5-en-20,22-dione-3-O-α-l-rhamnopyranosyl(1?→?2)-β-d-glucopyranoside (2); and (25R)-spirost-5-ene-3β,17α-diol-3-O-β-d-glucopyranosyl(1?→?4)-β-d-galactopyranoside (3) by spectroscopic techniques and chemical means.     

Analysis of bioactive constituents from the leaves of Amorpha fruticosa L.

Amorpha fruticosa L. is a Chinese folk medicine and rich in polyphenols. Fifteen known compounds were isolated and identified from the leaves of A. fruticosa L. They are tephrosin (1), 6a,12a-dehydrodeguelin (2), vitexin (3), afrormosin-7-O-β-d-glucopyranoside (4), 2″-O-α-l-rhamnopyranosyl isovitexin (5), rutin (6), chrysoeriol (7), 7-O-methylluteolin (8), trans-p-coumaric acid (9), 2-benzyl-4,6-dihydroxybenzoic acid-4-O-β-d-glucopyranoside (10), formononetin (11), quercetin (12), apigenin (13), β-sitosterol (14), and β-daucosterol (15). Compounds 3, 4, 5, and 7–9 were isolated from A. fruticosa L. for the first time. Cytotoxicity of individual compounds 3–10 and 90% ethanol extract against human cancer cell lines HCT116 and HepG2 were reported. The results suggested that compounds 7 and 8, and the crude extract exhibited inhibitory effects on human cancer cell line HCT116, at concentrations of 100 μg/mL, 5 μg/mL, and 25 μg/mL at <60% of cell viability rate, respectively. In addition, a valid high-performance liquid chromatography diode array detector method was established to quantitatively analyze compounds 1–12 in the leaves of A. fruticosa L., which was harvested at three different stages of maturity from May 20 to August 10, 2014. The results demonstrated that contents were greatly influenced by the maturity. Total amounts of the analytical constituents gradually increased from May 20 to August 10, with the values ranging from 10.86 mg/g to 18.84 mg/g, whereas bioactive compounds 7 and 8 presented the opposite variation trend. The results of this study may provide data for further study and comprehensive utilization of A. fruticosa L. resource.     

凤眼草化学成分的分离与鉴定

目的对凤眼草的质量分数95%乙醇提取物进行分离并鉴定。方法采用硅胶柱色谱、聚酰胺柱色谱等方法分离纯化,1H-NMR、13C-NMR等方法进行结构鉴定。结果分离得到5个黄酮类化合物,分别鉴定为kaempferol(1)、quercetin(2)、kaempferol3,7-O-bis-α-L-rhamnopyranoside(3)、kaempferol-3-O-α-L-arabinofuranosyl-7-O-α-L-rhamnopyranoside(4)、quercetin3-O-β-D-glucopyrano-side(5)。结论化合物3~5为首次从臭椿属植物中分离得到。     

Triterpenoids from the roots ofDipsacus asper

Four triterpenoids were isolated from the roots ofDipsacus asper. On the basis of chemical and spectral evidence, the structures of these compounds have been elucidated to be hederagenin (1), hederagenin 3-O-α-L-arabinoside (2). 3-O-α-L-arabinopyranosyl hederagenin 28-O-β-D-glucopyranosyl ester (3) and hederagenin 28-O-β-D-glucopyranosyl (1→6)-β-D-glucopyranosyl ester (4). The new glycoside,4, was named dipsacus saponin A.     

Flavonoid constituents in the leaves of Myrica rubra sieb. et zucc. with anti-inflammatory activity

The leaves of Myrica rubra sieb. et zucc. have been used in oriental traditional medicine for the treatment of burns, skin diseases, and as an antidiarrheal in China, Japan, and Korea. Activity guided isolation of the leaves of M. rubra has led to the isolation of five flavonoid: myricetin (1), myricitrin (2), myricetin 3-O-(2″-O-galloyl)-α-L-rhamnopyranoside (3), myricetin 3-O-(2″-O-galloyl)-β-D-galactopyranoside (4), and quercetin 3-O-(2″-O-galloyl)-β-D-galactopyranoside (5). All isolates were evaluated for their antioxidant potency against the superoxide anion (O₂ ^?), and compounds 3–5 showed potent scavenging activities with 50 % inhibition concentration (IC₅₀) values compared to the positive control, allopurinol. Compounds 1–5 were evaluated as inhibitors of various macrophage functions involved in the inflammatory process. These five compounds significantly and dose dependently inhibited lipopolysaccharide (LPS)-stimulated nitric oxide (NO), pro-inflammatory cytokines, and the protein levels of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in LPS-stimulated RAW 264.7 macrophages. Our results suggest that galloyl flavonol glycosides (3–5) isolated from M. rubra might be beneficial for the treatment of inflammation‐related diseases.     

Phytochemical analysis and anti-diabetic,anti-inflammatory and antioxidant activities of Loranthus acaciae Zucc. Grown in Saudi Arabia

The Loranthus genus has been demonstrated to be used in the treatment of wide range of diseases e.g. diabetes, inflammations and cancers. Many species of Loranthus represent a major source of biologically active constituents. Therefore, our study was carried out to investigate the anti-diabetic, anti-inflammatory and antioxidant effects of Loranthus acaciae Zucc. (Loranthaceae) grown in Saudi Arabia. Moreover, our research concerned the guided-fractionation and isolation of possible active compounds from this species. The crude ethanolic extract and its n-hexane, chloroform and n-butanol fractions were investigated for antidiabetic activity utilizing two methods namely, in alloxan-induced diabetic rats and glucose tolerance test in normal rats. Additionally, the anti-inflammatory activity was studied by the carrageenan-induced rat paw oedema method while DPPH free radical scavenging and β-carotene bleaching assays were utilized to determine the antioxidant activity. Various chromatographic and spectroscopic techniques were utilized for the isolation and characterization of the active compounds. Our results exhibited that the crude extract and chloroform fraction has the greatest hypoglycemic and antidiabetic effects. The chloroform fraction and crude extract produced at a dose of 500 mg/kg a significant hypoglycemic effect in diabetic rats with 47.0 and 33.6% reduction in blood sugar levels and in normoglycemic rats 35.6 and 35.4% respectively. A potent anti-inflammatory effect (67.2% at 500 mg/kg) was detected for the chloroform fraction. In addition, the chloroform fraction exhibited a high antioxidative and DPPH-radical inhibitory activity (85.4 and 88.3% respectively). The phytochemical analysis of L. acaciae led to the isolation and characterization of four compounds namely, quercetin 3-O-β-D-glucopyranoside (compound 1), quercetin 3-O-β-(6-O-galloyl)-glucopyranoside (compound 2), (-) catechin (compound 3), and catechin 7-O-gallate (compound 4). Among these compounds quercetin 3-O-β-D- glucopyranoside, quercetin 3-O-β-(6-O-galloyl)-glucopyranoside and catechin 7-O-gallate, are isolated for the first time from this plant.     

Phenolic and Terpenoid Constituents from the Sri Lankan Medicinal Plant Osbeckia aspera.

Abstract

A crude aqueous acetone extract of Osbeckia aspera. Blume (Melastomataceae), a plant from Sri Lanka used traditionally to treat liver disease, was fractionated by column and preparative paper chromatography, and the fractions were analyzed by high-performance liquid chromatography (HPLC) using diode array and mass spectrometric detection. Phenolic acids (gallic, protocatechuic, and ellagic acid), flavonol glycosides [quercetin 3-O.-β-galactopyranoside, quercetin 3-O.-β-glucopyranoside, kaempferol 3-O.-β-glucopyranoside, and kaempferol 3-O.-(6″-O.-p.-coumaroyl-β-glucopyranoside) (tiliroside)] and flavonol aglycones (quercetin and kaempferol) were identified by comparison of their retention times, UV and MS spectra with those of authentic standards. Five compounds from a methanol extract were identified by NMR spectroscopy as the flavonol glycosides, quercetin 3-O.-(3″-O.-acetyl-β-galactopyranoside) and kaempferol 3-O.-[2″,6″-di-O.-(E.,E.)-p.-coumaroyl-β-glucopyranoside], and the norsesquiterpenoids 6,9-dihydroxy-4,7-megastig-madien-3-one, 9-hydroxy-4,7-megastigmadien-3-one and 9-hydroxy-4-megastigmen-3-one. A crude water extract, 50% acetone extract and fractions from this extract, a 100% methanol extract, and three of the phenolic acids in the fractions were tested for in vitro. hepatoprotective activity against bromobenzene and 2,6-dimethyl-N.-acetyl p.-quinoneimine toxicity to HepG2 liver-derived cells. The crude water extract showed protective activity against both liver toxins, whereas the fractions and compounds were more protective against 2,6-dimethyl-N.-acetyl p.-quinoneimine than bromobenzene. Of the three phenolic acids present in the extracts that were tested, gallic and protocatechuic acids were more active at protecting the liver cells from the two toxic compounds than ellagic acid.     

Novel quercetin glucosides from Helminthostachys zeylanica root and acceleratory activity of melanin biosynthesis

Two novel quercetin glucosides, namely 4′-O-β-d-glucopyranosyl-quercetin-3-O-β-d-glucopyranosyl-(1→4)-β-d-glucopyranoside (compound 1) and 4′-O-β-d-glucopyranosyl-(1→2)-β-d-glucopyranosyl-quercetin-3-O-β-d-glucopyranosyl-(1→4)-β-d-glucopyranoside (compound 2), were isolated from Helminthostachys zeylanica root 50 % EtOH extract. Structural analysis of isolated compounds was achieved mainly by 600 MHz and 800 MHz NMR, UPLC–TOFMS and GC–MS. Of the two quercetin glucosides, compound 1 showed a high melanogenic acceleratory effect, 2.7 times higher than control, at 10 μM concentration in murine B16 melanoma cells, with no cytotoxic effect.