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1.
Four new β-carboline alkaloids, eudistomidins H-K (1-4), were isolated from an Okinawan marine tunicate Eudistoma glaucus and the structures of 1-4 were elucidated on the basis of spectroscopic data. Eudistomidins H (1) and I (2) were new β-carboline alkaloids possessing a unique fused-tetracyclic ring system consisting of a tetrahydro β-carboline ring and a hexahydropyrimidine ring. Eudistomidin J (3) showed relatively potent cytotoxicity against murine leukemia cells P388 and L1210, and human epidermoid carcinoma cells KB in vitro. 相似文献
2.
Xiao WL Huang SX Wang RR Zhong JL Gao XM He F Pu JX Lu Y Zheng YT Zheng QT Sun HD 《Phytochemistry》2008,69(16):2862-2866
Nortriterpenoids, sphenadilactone C (1) and sphenasin A (2), together with four known lignans (3-6), were isolated from the leaves and stems of Schisandra sphenanthera. Their structures were elucidated by extensive analysis of 1D and 2D NMR spectroscopic data and compound 2 was further confirmed by single-crystal X-ray diffraction. Compound 1 features a partial enol moiety and an acetamide group in its structure. In addition, compounds 1, 3-6 showed weak anti-HIV-1 activity with EC50 values in the range of 15.5-29.5 μg/mL. 相似文献
3.
Marcelo Telascrea Carla C. de Araújo Márcia O.M. Marques Roselaine Facanali Pedro L.R. de Moraes Alberto J. Cavalheiro 《Biochemical Systematics and Ecology》2007
The composition of the essential oil from leaves of Cryptocarya mandioccana has been determined by chromatographic fractionation and GC–FID, GC–MS and 13C NMR analyses, yielding the identification of 64 compounds with predominance of isomeric sesquiterpenes with molecular weights of 204. The main components of the oil obtained by hydrodistillation were β-caryophyllene, spathulenol, caryophyllene oxide, δ-cadinene, germacrene D, benzaldehyde and bicyclogermacrene. However, the oil obtained by steam distillation contained higher levels of sesquiterpene hydrocarbons, with predominance of β-caryophyllene (C), germacrene D (G) and bicyclogermacrene (B), and was considered to be more representative of the composition of the oil in its natural state. The intraspecific chemical variability of the essential oil obtained by steam distillation was evaluated within populations of trees growing at three separate locations in the state of São Paulo, Brazil. Three distinct chemical groups could be characterised due to differences in the relative percentages of the three main sesquiterpenes from essential oil: CGB [relative contents of C (14–34%), G (5–28%), B (8–15%)], BCG [B (17–34%), C (9–24%), G (12–25%)] and GCB [G (22–42%), C (4–17%), B (7–15%)]. Individuals from groups CGB and BCG were found to be more frequent at south locations while group GCB is predominant in north location. 相似文献
4.
The extracts of a selection of 150 foliar fungal endophytes isolated from Picea rubens (red spruce) needles were screened by LC-MS and assayed for toxicity. Three of these strains that were toxic to the forest pest Choristoneura fumiferana (eastern spruce budworm) in dietary bioassays were selected for further study. Their culture extracts were analyzed by LC-NMR spectroscopy, and the major metabolites were isolated by LC-MS-SPE or PTLC/column chromatography and characterized. The structures were elucidated by spectroscopic analyses including 2D NMR, HRMS and by comparison to literature data. Compounds 1 and 5-7 are hitherto unknown whereas compounds 2 and 3 are natural products described for the first time. Compound 4 is reported for the first time as a fungal metabolite and 8-9 were identified as known fungal metabolites in genera. 相似文献
5.
Radwan MM Elsohly MA Slade D Ahmed SA Wilson L El-Alfy AT Khan IA Ross SA 《Phytochemistry》2008,69(14):2627-2633
Six new non-cannabinoid constituents were isolated from a high potency Cannabis sativa L. variety, namely 5-acetoxy-6-geranyl-3-n-pentyl-1,4-benzoquinone (1), 4,5-dihydroxy-2,3,6-trimethoxy-9,10-dihydrophenanthrene (2), 4-hydroxy-2,3,6,7-tetramethoxy-9,10-dihydrophenanthrene (3), 4,7-dimethoxy-1,2,5-trihydroxyphenanthrene (4), cannflavin C (5) and β-sitosteryl-3-O-β-d-glucopyranoside-2′-O-palmitate (6). In addition, five known compounds, α-cannabispiranol (7), chrysoeriol (8), 6-prenylapigenin (9), cannflavin A (10) and β-acetyl cannabispiranol (11) were identified, with 8 and 9 being reported for the first time from cannabis. Some isolates displayed weak to strong antimicrobial, antileishmanial, antimalarial and anti-oxidant activities. Compounds 2-4 were inactive as analgesics. 相似文献
6.
7.
Namdeo N. Bhujbal 《Carbohydrate research》2009,344(6):734-2895
Synthesis of catechuic acid (1) and ethyl 2,4,5-trihydroxybenzoate (2) from d-glucose-derived β-ketoester is described. The polyhydroxylated β-ketoester obtained from the hydrolysis of sugar β-ketoester 3 was subjected to an aldol-type condensation to get 4 that on enolization, dehydration, and hydrogenation afforded ethyl 2,4,5-trihydroxybenzoate (2). On the other hand, hydrogenation of aldol product 4 afforded polyhydroxylated keto-carbasugar 6, which on mild acid treatment and ester hydrolysis in basic media led to catechuic acid 1. Intermediate 4 is co-related to 3-dehydroshikimic acid, a biochemical intermediate from d-glucose in the synthesis of pro-catechuic acid. 相似文献
8.
Aher RB Wanare G Kawathekar N Kumar RR Kaushik NK Sahal D Chauhan VS 《Bioorganic & medicinal chemistry letters》2011,21(10):3034-3036
A series of dibenzylideneacetones (A1-A12) and some of their pyrazolines (B1-B4) were synthesized and evaluated in vitro for blood stage antiplasmodial properties in Plasmodium falciparum culture using SYBR-green-I fluorescence assay. The compound (1E, 4E)-1,5-bis(3,4-dimethoxyphenyl)penta-1,4-dien-3-one (A9) was found to be the most active with IC50 of 1.97 μM against chloroquine-sensitive strain (3D7) and 1.69 μM against chloroquine-resistant field isolate (RKL9). The MTT based cytotoxicity assay on HeLa cell line has confirmed that A9 is selective in its action against malaria parasite (with a therapeutic index of 166). Our results revealed that these compounds exhibited promising antiplasmodial activities which can be further explored as potential leads for the development of cheaper, safe, effective and potent drugs against chloroquine-resistant malarial parasites. 相似文献
9.
Regioselective facile one-pot synthesis of 16 different sugar-based quinoline, naphthyridine, and xanthone derivatives is reported. The compounds are characterized by NMR spectroscopy and elemental analysis. The β-Anomeric form of the sugar moiety was identified from 1H NMR studies. Antimicrobial studies of these sugar-heterocyclic derivatives, 3a, 3b, 3f, 5c, 7a, 7b, and 7c show excellent activity against different microbes. 相似文献
10.
Cui YM Wang H Liu QR Han M Lu Y Zhao CQ 《Bioorganic & medicinal chemistry letters》2011,21(15):4400-4403
Two new flavans (1, 2) and a new flavanone (3), together with three known compounds (4-6), were isolated from the roots of Iris tenuifolia. Their structures were elucidated by means of spectroscopic methods including 1D and 2D NMR techniques and mass spectrometry. Compounds 1, 4, and 6 were further confirmed by single-crystal X-ray diffraction analysis. Biological evaluation showed that compounds 1 and 4 were positive in inhibiting β-amyloid (Aβ) aggregation and promoting neural stem cells (NSCs) proliferation, respectively. 相似文献
11.
Yanxiang Cheng 《Inorganica chimica acta》2009,362(13):4678-4684
The crystalline compounds [LnCl2(L)(thf)2] [Ln = Ce (1), Tb (2), Yb (3)], [NdI2(L)(thf)2] (4), [LnCl(L′)2] [Ln = Tb (5), Yb (6) (a known compound)] and [YbCl(L′′)(μ-Cl)2Li(OEt2)2] (7) have been prepared [L = {N(C6H3Pri2-2,6)C(H)}2CPh, L′ = {N(SiMe3)C(Ph)}2CH, L′′ = {N(SiMe3)C(C6H4Ph-4)}2CH]. The X-ray molecular structures of 2-7 have been established; in each, the monoanionic ligand L, L′ or L′′ is N,N′-chelating and essentially π-delocalised. Each of 1-7 was prepared from the appropriate LnCl3, or for 4 [NdI3(thf)2], and an equivalent portion of the appropriate alkali metal [Li for 7, Na for 2, 3 and 5, or K for 1, 4 and 6] β-diiminate in thf; the isolation of exclusively 5 and 6 (rather than the L′ analogues of 2 or 3) is noteworthy, as is the structure of 7 which has no precedent in Group 3 or 4f metal β-diiminato chemistry. 相似文献
12.
Chung SC Lee SH Jang KH Park W Jeon JE Oh H Shin J Oh KB 《Bioorganic & medicinal chemistry letters》2011,21(11):3198-3201
Oxazole-containing macrolides (1-5) isolated from the marine sponge Chondrosia corticata were evaluated for their actin depolymerizing activities by monitoring fluorescent intensity of pyrene F-actin. These studies led to the identification of (19Z)-halichondramide (5) as a new actin depolymerizing agent. The actin depolymerizing activity by (19Z)-halichondramide (5) was four times more potent than that of halichondramide (1). Compounds 1 and 5 also have potent antifungal activity. The preliminary structure-activity relationship of these compounds is described to elucidate the essential structural requirements. 相似文献
13.
Bringmann G Rüdenauer S Irmer A Bruhn T Brun R Heimberger T Stühmer T Bargou R Chatterjee M 《Phytochemistry》2008,69(13):2501-2509
From the methanolic extracts of solid callus cultures from two species of the closely related palaeotropical plant families Dioncophyllaceae and Ancistrocladaceae seven new natural naphthoquinones were isolated, dioncoquinones A (4) and B (5) from Triphyophyllum peltatum, and ancistroquinones B (6), C (7), D (9), E (10), and F (12) from Ancistrocladus abbreviatus. Their structures were elucidated by spectroscopic, chemical, and computational methods. Furthermore, the already known naphthoquinones plumbagin (2), droserone (3), malvone A (8), and nepenthone A (11) were found in the extract of A. abbreviatus. Dioncoquinones A (4) and B (5) showed good - and specific - activity against Leishmania major, while they were not active against other protozoic parasites. Moreover, treatment with 4 and 5 strongly induced apoptosis in human tumor cells derived from two different B cell malignancies, B cell lymphoma and multiple myeloma, without any significant toxicity towards normal peripheral mononuclear blood cells. 相似文献
14.
Sergio Rosselli Antonella Maggio Muhammad Safder Chin-Yu Lai Kuo-Hsiung Lee 《Phytochemistry》2011,72(9):942-945
The analysis of the aerial parts of Bonannia graeca led to the isolation and characterization of polar geranylated flavonoids (6 and 7). The structure elucidation was performed by extensive spectroscopic methods (1D and 2D NMR) and comparison with literature data. All natural flavonoids isolated from B. graeca (1-7) and some synthetic derivatives (8-11) were tested for cytotoxic activity against four human tumor cell lines. Preliminary structure-activity relationship correlations are discussed. 相似文献
15.
The phenyl - and -L-idopyranosiduronic acids and some other aryl glycopyranosiduronic acids 总被引:3,自引:0,他引:3
Condensation of 1,2,3,4,6-penta-O-acetyl-á-l-idopyranose (1) with phenol yielded phenyl 2,3,4,6-tetra-O-acetyl-α- (2) and α-l-idopyranoside (4). Deacetylation of 2 and 4 afforded phenyl α and β-l-idopyranosides (3 and 5), respectively, the structures of which were verified by periodate oxidation studies. A platinum-catalyzed oxidation of 3 and 5 produced the amorphous phenyl α- and β-L-idopyranosiduronic acids (9 and 11), respectively, which were isolated as the crystalline cyclohexylammonium salts. Phenyl β- and α-d-glucopyranosiduronic acids are apparent minor byproducts of the catalytic oxidations, resulting from an inversion at C-5. p-Nitrophenyl α-d-mannopyranosiduronic acid and p-nitrophenyl α- and β-d-galactopyranosiduronic acids are also described. 相似文献
16.
Three new compounds (3, 7, and 11) together with eight known phytoecdysteroids (1, 2, 4-6, and 8-10) were isolated from the rhizomes of common polypody, Polypodium vulgare L. The structures of compounds were elucidated by spectroscopic methods including 1D and 2D NMR measurements. The 1H and 13C NMR assignments of compounds 1, 6, 9 and 10 are included. 相似文献
17.
Matthew S. Varonka 《Inorganica chimica acta》2007,360(1):317-328
The β-diketiminato zinc halide [Me2NN]ZnCl2Li(THF)3 (1) is prepared in 51% isolated yield by addition of the lithium β-diketiminate Li[Me2NN] to ZnCl2 in THF. Reaction of 1 with 2 equiv. of the thallium thiolate TlSCy provides {[Me2NN]Zn(μ-SCy)2Tl}2 (2), a TlSCy adduct of [Me2NN]ZnSCy, as colorless crystals in 51% yield. Reaction of 1 with 1 equiv. TlSR provides the dinuclear {[Me2NN]Zn(μ-SR)}2 (R = Cy (3), tBu (4)) which possess unsymmetrically bridging thiolate ligands with pairs of dissimilar Zn-S distances in the solid state (2.350(3) and 2.417(3) Å for 3; 2.312(1) and 2.415(1) Å for 4). Reaction of 1 with LiSCPh3 results in the mononuclear zinc thiolates [Me2NN]ZnSCPh3(THF) (5) and [Me2NN]ZnSCPh3 (6) with shorter, but similar Zn-SR distances of 2.225(2) and 2.214(1) Å. Variable temperature 1H NMR studies of 3 and 4 in CDCl3 suggest that the aliphatic thiolates exist predominately as monomeric species in solution near room temperature, though at −50 °C two different β-diketiminato species are observed for 3. Thiolate exchange among 3, 4, and 6 also takes place on the NMR timescale near room temperature. Both 4 and 6 undergo transnitrosylation with CySNO in CDCl3 to give {[Me2NN]ZnSCy}2 (3) and the corresponding S-nitrosothiol tBuSNO or Ph3CSNO. Nitric oxide does not react with 4 or 6 under anaerobic conditions, but in the presence of O2, NO cleaves the zinc-thiolate bond of 4 to rapidly give tBuSNO. Similarly, anaerobic NO2 reacts with 4 to give tBuSNO providing insight into the active nitrogen oxide species capable of cleaving Zn-SR bonds. 相似文献
18.
Maldaner G Marangon P Ilha V Caro MS Burrow RA Dalcol II Morel AF 《Phytochemistry》2011,72(8):804-809
Scutianene E (1), 3,4,28-tris-epi-scutiaene E (2), 28-epi-scutianene E (3) and scutianene L (4), four neutral cyclopeptide alkaloids, were isolated from Scutia buxifolia Reiss, together with four known cyclopeptide alkaloids, scutianines B, C, D and E. Scutianenes 1-3 are diastereoisomeric compounds, with 3-hydroxyleucine as a β-hydroxy amino acid unit, which is connected to the styryl fragment via an ether bridge, β-phenylserine, as a common ring-bonded amino acid residue. Attached to the amino group of β-hydroxyamino acid is a side chain [trans-CH = CH-Ph]. The structures of the peptides were elucidated by means of spectroscopic analysis, including extensive 2D NMR studies. The stereochemistry for the diastereomeric 3,4,28-tris-epi-scutiaene E and 28-epi-scutianene E was confirmed by X-ray diffraction analysis of their O-acetyl derivatives. 相似文献
19.
Porntep Chomcheon Suthep Wiyakrutta Nattaya Ngamrojanavanich Surapong Kengtong Somsak Ruchirawat Prasat Kittakoop 《Phytochemistry》2009,70(3):407-413
Isolation of a broth extract of the endophytic fungus Corynespora cassiicola L36 afforded three compounds, corynesidones A (1) and B (3), and corynether A (5), together with a known diaryl ether 7. Compounds 1, 3, 5, and 7 were relatively non-toxic against cancer cells, and inactive toward normal cell line, MRC-5. Corynesidone B (3) exhibited potent radical scavenging activity in the DPPH assay, whose activity was comparable to ascorbic acid. Based on the ORAC assay, compounds 1, 3, 5, and 7 showed potent antioxidant activity. However, the isolated natural substances and their methylated derivatives (1−8) neither inhibited superoxide anion radical formation in the XXO assay nor suppressed TPA-induced superoxide anion generation in HL-60 cell line. Corynesidone A (1) inhibited aromatase activity with an IC50 value of 5.30 μM. 相似文献
20.
Hirotaka Takahashi Akihiko Ozawa Keiichirou Nemoto Akira NozawaMotoaki Seki Kazuo ShinozakiHiroyuki Takeda Yaeta Endo Tatsuya Sawasaki 《FEBS letters》2012,586(19):3134-3141
Plant genome possesses over 100 protein phosphatase (PPase) genes that are key regulators of signal transduction via phosphorylation/dephosphorylation event. Here we report a comprehensive functional analysis of protein serine/threonine, dual-specificity and tyrosine phosphatases using recombinant PPases produced by wheat cell-free protein synthesis system. Eighty-two recombinant PPases were successfully produced using Arabidopsis full-length cDNA as templates. In vitro PPase assay was performed using phosphorylated myelin basic protein as substrate. Among the AtPPases examined, 26 serine/threonine, three dual-specificity and one tyrosine PPases exhibited catalytic activity, including 20 serine/threonine and one dual-specificity PPases that showed in vitro activities for the first time. Our study demonstrates genome-wide biochemical analysis of AtPPases using wheat cell-free system, and provides new information and insights on enzyme activities.