A further study of the cytotoxic constituents of a milnamide-producing sponge

A reinvestigation of Auletta sp. yielded the novel compound milnamide C (3) plus the known compounds milnamide A (1), milnamide B (hemiasterlin) (2), jasplakinolide (5), and geodiamolides A (6), D (7), E (8), and G (9). The isolation work was guided by cytoskeletal bioactivity data. Compounds 2 and 3 were shown to cause microtubule depolymerization, and 6-9 were shown to cause microfilament disruption. This biological activity and the structural elucidation of 3, including X-ray analysis, are reported here. [structure: see text]     

A New Quinolizidine Alkaloid from Boehmeria siamensis

Boehmeria siamensis Craib is distributed in China, Vietnam, Laos and Thailand1. The whole plants of B. siamensis were used in folk medicine2,3. Previous studies on the plants of this genus led to the isolation of different compounds such as alkaloids, flavones, lignans, triterpenoids and its glycosides4-9. Some antimicrobial alkaloids were obtained from B. cylindrical4. In the investigation of the whole plant of B. siamensis, a new alkaloid, 3-(4-hydroxyphenyl)-4-(3-methoxy -4-hydroxypheny…     

A New Triterpenoid Saponin from Anemone tomentosa

TherootsofAnemonetomentosa(Maxim.)PeiareusedasafolkmedicineforthetreatmentofdysenteriainChinal.Recently,twonewcoumarinsandnineknowncompoundswereisolatedfromtheethylacetateeXtractwhichexhibitedstrongantifeedantactivityagainstLeucaniaSeparataWailiee.Duringthefurtherinvestigationofthetitleplant,anewminorsaponin,tomentoside,togetherwithfourknownoneswasisolated.Tomentoside(5),amorphouspowder,[a]D-41.5(MeOH,c0.26).MolecularformulawasdeterminedasC,,H,,.O,.byHRFABMS,m/zf1497.7166([M-H]-),caf…     

Cytotoxic diterpenoids from Podocarpus madagascariensis from the Madagascar rainforest

Bioassay-directed fractionation of an extract of the root and bark of Podocarpus madagascariensis resulted in the isolation of a new totarol diterpenoid (1) in addition to the three known cytotoxic diterpenoids 19-hydroxytotarol (2), totaradiol (3), and 4beta-carboxy-19-nor-totarol (4). The structure of the new compound 1 was established as methyl-13-hydroxy-14-isopropyl-9(11),12,14(8)-podocarpatriene-19-oate on the basis of 1D and 2D NMR spectroscopic interpretation and methylation of 4. All the compounds exhibited cytotoxic activity against the A2780 ovarian cancer cell line.     

Puerariafuran, a new inhibitor of advanced glycation end products (AGEs) isolated from the roots of Pueraria lobata

A new 2-arylbenzofuran, puerariafuran (1), as well as three known compounds, coumestrol (2), daidzein (3), and genistein (4), were isolated from a MeOH extract of the roots of Pueraria lobata as active constituents, using an in vitro bioassay based on the inhibition of advanced glycation end products (AGEs) to monitor chromatographic fractionation. The structure of 1 was determined by spectroscopic data interpretation, particularly by extensive 1D and 2D NMR studies. All the isolates (1-4) were evaluated for the inhibitory activity on AGEs formation in vitro.     

Structure elucidation and complete NMR spectral assignments of a new taxane glycoside from the needles of Taxus cuspidata

A new taxane glycoside was isolated from a methanol extract of the needles of Taxus cuspidata. The structure was established as 2alpha,9alpha,10beta-triacetoxytaxa-4(20),11-dien-13-one-5alpha-O-beta-D-glucopyranoside (1) on the basis of 1D- and 2D NMR and high-resolution fast atom bombardment mass spectral analyses.     

Iridoid glycosides from Globularia davisiana

From the ethanolic extract of the aerial parts of Globularia davisiana, a new iridoid glycoside, davisioside (1), was isolated. Davisioside (1) comprises a rare iridoid aglycone structure with a saturated double bond between C-3 and C-4. Nine known iridoid glycosides, asperuloside (2), alpinoside (3), geniposide (4), globularin (5), globularicisin (6), 10-O-benzoylcatalpol (7), lytanthosalin (8), melampyroside (9), agnuside (10), and three known phenylethanoid glycosides, verbascoside, isoacteoside and leucosceptoside A were also isolated and characterized. The structures of the isolates were established by spectroscopic methods (one-dimensional (1D)- and two-dimensional (2D)-NMR, MS).     

A novel 18-norclerodane diterpenoid from the roots of Tinospora sagittata var. yunnanensis

A novel 18-nor-clerodane diterpenoid named sagitone (1) was isolated from the 95% ethanol extract of dry roots of Tinospora sagittata var. yunnanensis together with the five known diterpenoids columbin (2), palmatoside C (3), fibleucin (4), tinophylloloside (5) and epitinophylloloside (6). The structure of the new compound 1 was determined based on MS, IR, 1D and 2D NMR spectral data. The compounds 1-6 did not show significant cytotoxic activity against cancer cell lines K562 and HL-60.     

Izumiphenazine D, a new phenazoquinoline N-oxide from Streptomyces sp. IFM 11204

A new phenazine derivative named izumiphenazine D (1), together with three known metabolites, 1-hydroxyphenazine (2), phenazine-1-carboxylic acid (3) and 6-hydroxyphenazine-1-carboxylic acid (4) has been isolated from the ethyl acetate extract of culture of Streptomyces sp. IFM 11204. The structure of 1 was established via spectroscopic methods, including 1D- and 2D-NMR measurements.     

Rearranged lanostane triterpenoids from Abies sachalinensis (III)

To isolate more rearranged lanostane-type triterpenes from Abies sachalinensis, continuous chemical investigation of the ethyl acetate soluble fraction of the methanol extract of A. sachalinensis afforded two new rearranged lanostane-type triterpenes (1, 2). Their structures were elucidated to be 3,4-seco-4(28),7,12,24-mariesatetraen-26,23-olide-23-hydroxy-3-oic acid (1) and ethyl 3,4-seco-8(14-->13R)abeo-17,13-friedo-4(28),7,14,24-lanostatetraen-26,23-olide-23-hydroxy-3-oate (2), respectively. The structure of these compounds was determined by spectral studies, especially by two-dimensional (2D)-NMR and high-resolution (HR)-MS. Compounds 1 and 2 have a tautomeric lactone structure in the side chain.     

Isolation and identification of a new neo-clerodane diterpenoid from Teucrium chamaedrys L.

Teucrium chamaedrys L. is an aromatic and medicinal plant used as traditional medicine. Aerial parts of the plant material were dried and extracted with hexane–dichloromethane (extract 1), ethyl acetate–dichloromethane (extract 2) and methanol–dichloromethane (extract 3) in a ratio of 1:1 at rt successively. The solvents were evaporated to give crude extracts. Extract 1 was suspended in water at 60°C then partitioned successively with hexane and ethyl acetate to give hexane and ethyl acetate portions. After the column chromatography (silica gel) of ethyl acetate extract, one new and four known compounds were isolated. The new compound was named as 1(12S,18R)-15,16-epoxy-2β,6β-dihydroxy-neo-cleroda-13(16),14-dien-20,l2-olide-l8,l9-hemiacetal (teuchamaedryn D) (4). The known compounds were teucrin A (1), dihydroteugin (2), teucroxide (3), syspirensin A (5). The chromatographic methods were also applied for extract 3 to isolate verbascoside (6) and teucrioside (7). The structure of isolated compounds was elucidated by spectroscopic methods including LC-TOF/MS, 1D NMR and 2D NMR.     

A new flavanone glycoside from the dried immature fruits of Poncirus trifoliata

A new flavanone glycoside, (2R)-5-hydroxy-4'-methoxyflavanone-7-O-{beta-glucopyranosyl-(1-->2)-beta-glucopyranoside} (1), was isolated from the EtOAc extract of dried immature fruit of Poncirus trifoliata, together with three known compounds, (2S)-poncirin (2), (2S)-naringin (3), and (2S)-poncirenin (4). The structure of compound 1 was elucidated by spectroscopic data analysis, including 1D and 2D NMR experiments. Among the isolates, compound 2 exhibited considerable inhibitory activity against lipopolysaccharide (LPS)-induced prostaglandin E(2) (PGE(2)) and interleukin-6 (IL-6) production, and mRNA expression in RAW 264.7 murine macrophage cells.     

A new anti-diabetic sesquiterpenoid from Acorus calamus

A new sesquiterpenoid,1β,5α-guaiane-4β,10α-diol-6-one(1),was isolated from 70%EtOH extract of the rhizomes of Acorus calamus.The structure was determined on spectroscopic methods,especially 2D NMR techniques.The absolute configuration of 1 was confirmed by TDDFT quantum chemical calculation of its ECD spectrum.Compound 1 showed promising anti-diabetic activity on a insulin-mediated glucose consumption model of HepG2 cells.     

Isolation of a novel flavanone 6-glucoside from the flowers of Carthamus tinctorium (Honghua) by high-speed counter-current chromatography

A novel flavanone glycoside, (2S)-4',5,6,7-tetrahydroxyflavavone 6-O-beta-D-glucopyranoside was isolated from the ethyl acetate extract of the flowers of Carthamus tinctorium by high-speed counter-current chromatography (HSCCC). Using an optimized two-phase solvent system composed of ethyl acetate-methanol-water (5:1:5, v/v), target compound (52 mg) with purity of 98.0% was obtained from 2.0 g of sample by HSCCC in seven times run. The structure of the target compound was elucidated by means of spectroscopic methods including IR, MS, 1D and 2D NMR techniques.     

Acaricidal daphnane diterpenoids from Trigonostemon reidioides (KURZ) CRAIB roots

A new daphnane diterpenoid, rediocide F (1), was isolated together with three known compounds, rediocides A (2), C (3) and E (4), from the hexane extract of Trigonostemon reidioides roots by bioassay-guided fractionation for acaricidal activity on Dermatophagoides pteronyssinus, Thai common house dust mite. The structure of rediocide F (1) was established as the demethyl analog of rediocide C (3) on the basis of spectral analysis. Compounds 1-4 exhibited potent activity against D. pteronyssinus with respective LC50 values of 2.53, 0.78, 5.59 and 0.92 microg/cm2.     

New constituents from the rhizomes of Egyptian Iris germanica L

Chemical investigation of the methanolic extract of the rhizomes of Iris germanica L. (Iridaceae) afforded two new compounds; irigenin S (7) and iriside A (12), together with ten known compounds: stigmasterol (1), a-irone (2), γ-irone (3), 3-hydroxy-5-methoxyacetophenone (4), irilone (5), irisolidone (6), irigenin (8), stigmasterol-3-O-β-D-glucopyranoside (9), irilone 4'-O-β-D-glucopyranoside (10) and iridin (11). Their structures were established by UV, IR, 1D (1H and 13C) and 2D (1H-1H COSY, HMQC, and HMBC) NMR spectroscopy, in addition to mass spectroscopic data and comparison with literature data. The methanolic extract was evaluated for its antimicrobial activity. Both the methanolic extract and the isolated flavonoids were tested for their anti-inflammatory activity.     

Amplexicine, an antioxidant flavan-3-ol from Polygonum amplexicaule

Bioassay guided fractionation of an ethanolic extract of Polygonum amplexicaule D. Don led to the isolation of amplexicine, a new flavan-3-ol (1), along with khellactone (2). The structure of the isolates was established by UV, IR, HRESI/MS and NMR, including 1D and 2D experiments. Compound 1 exhibited considerable antioxidant activity in a 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging assay.     

Lignans from Arctium lappa and their inhibition of LPS-induced nitric oxide production

A new butyrolactone sesquilignan, isolappaol C (1), together with four known lignans, lappaol C (2), lappaol D (3), lappaol F (4), and diarctigenin (5), were isolated from the methanolic extract of the seeds from the Arctium lappa plant. The structure of isolappaol C (1) was determined by spectral analysis including 1D- and 2D-NMR. All the isolates were evaluated for their inhibitory effects on the LPS-induced nitric oxide production using murine macrophage RAW264.7 cells. Lappaol F (4) and diarctigenin (5) strongly inhibited NO production in the LPS-stimulated RAW264.7 cells with IC(50) values of 9.5 and 9.6 microM, respectively.     

Flavonoid constituents and free radical scavenging activity of Alchemilla mollis

Antioxidant capacity of the methanolic extract of Alchemilla mollis was measured by its ability to scavenge the DPPH radical. The EtOAc fraction obtained after partition of the total extract was found to be the most active radical scavenger (IC50 9.8 +/- 1.8 microg/mL) and was subjected to fractionation by Sephadex LH-20 CC. Further purification by RP-18 CC led to the isolation of eight flavonoid glycosides: cis- and trans-tiliroside (1 and 2), rhodiolgin (3), hyperoside (4), isoquercitrin (5), miquelianin (6), sinocrassoside D2 (7), and gossypetin-3-O-beta-D-galactopyranosyl-7-O-alpha-L-rhamnopyranoside (8). It was found that 8 is a new compound and its antioxidant activity is also reported. Identification of the isolated compounds was carried out by spectroscopic and spectrometric analysis (1D and 2D NMR, UV and MS).     

Fusaroside, a unique glycolipid from Fusarium sp., an endophytic fungus isolated from Melia azedarach

Fusaroside (1), a unique trehalose-containing glycolipid composed of the 4-hydroxyl group of a trehalose unit attached to the carboxylic carbon of a long-chain fatty acid, was isolated from the organic extract of fermentation broths of an endophytic fungus, Fusarium sp. LN-11 isolated from the leaves of Melia azedarach. Six known compounds, phalluside (2), (9R*,10R*,7E)-6, 9,10-trihydroxyoctadec-7-enoic acid (3), porrigenic acid (4), (9Z)-2,3-dihydroxypropyl octadeca-9-enoate (5), cerevisterol (6) and ergokonin B (7), were also isolated from this fungus. The glycolipid contains a rare branched long-chain fatty acid (C(20:4)) with a conjugated diene moiety and a conjugated ketone moiety. The structure of the new compound 1 was elucidated by spectroscopic methods (1D and 2D NMR experiments, MS) and chemical degradations. The metabolites 1-5 were shown to have moderate to weak active against the brine shrimp larvae. To our knowledge, this is the first report of isolation of the first representative of a new family of glycolipids from natural sources.