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1.
Salvatore A. Sparace J.Brian Mudd Basil A. Burke Arne J. Aasen 《Phytochemistry》1984,23(11):2693-2694
The structure of pyrenocine C, a new metabolite isolated from onion pink root fungus, Pyrenochaeta terrestris (Hansen) has been elucidated as (±)-(2′E)-5-(1′-hydroxybut-2′-enyl)-4-methoxy-6-methyl-2-pyrone by spectroscopic methods and chemical correlation with pyrenocine A. 相似文献
2.
The wood of Zollernia paraensis contains (+)-medicarpin, (+)-vestitol, isoliquiritigenin, formononetin, (±)-7-hydroxy-4′-methoxyisoflavanone, (±)-liquiritigenin and (+)-α-2′,4,4′-tetrahydroxydihydrochalcone. 相似文献
3.
The biosynthetic relations between protoberberine-, benzo[C]phenanthridine- and B-secoprotoberberine type alkaloids were demonstrated by use of (±)-tetrahydrocoptisine-[8,14-3H HCl, (±)-tetrahydrocorysamine-[8,14-3H]HCl and corynoline-[6-3H]HCl in Corydalis incisa, and the following results were presented. (±)-Tetrahydrocoptisine was converted to corynoline, corydalic acid methyl ester and corydamine hydrochloride. (±)-Tetrahydrocorysamine was converted to corynoline and corydalic acid methyl ester. Evidence that N-methyl-3-[6′-(3′,4′-methylenedioxyphenethylalcohol)]-4-methyl-7,8-methylenedioxy-1,2,3,4-tetrahydroisoquinoline-[α-3H] HCl was incorporated into corynoline-[11-3H] indicates the occurrence of the ring fission at C6-N followed by linking ofthe C6 and C13 positions in (±)-tetrahydrocoptisine and (±)-tetrahydrocorysamine, and suggests the participation of one of two possible intermediates in the biosynthesis of these alkaloids. 相似文献
4.
The debarked roots of Tamarix nilotica contain the furanofuran lignan (±)-syringaresinol so far not reported from the Tamaricaceae, and the new natural product ellagic acid 3,3′-dimethyl ether 4-O-β-d-glucopyranoside. Further constituents were isoferulic acid, gallic acid, dehydrodigallic acid and ellagic acid. The structure of the isolated compounds was determined mostly by 1H and 13C NMR spectroscopy. 相似文献
5.
The synthesis of (±)-licarin-B, a neolignan of Licaria aritu Ducke (Lauraceae), was achieved by pyrolysis of 3-hydroxy-3-piperonyl-1-propyl-2-methoxy-4-(E)-propenylphenyl ethers. 相似文献
6.
The trunk wood of Iryanthera elliptica Ducke (Myristicaceae) contains, besides 2-(ω-piperonyltridecyl) -4-methylidenetetronic acid (iryelliptin), three biogenetically related compounds: (±)-7,4′-dihydroxy-3′-methoxyflavan, 1-(4′-hydroxy-2′-methoxyphenyl)- 3-(4″-hydroxy-3″-methoxyphenyl)-propane and spiro-[3-methoxy-2,5-cyclohexadien-1.1′-6′,7′- dihydroxy-5′-methoxy-1′,2′,3′,4′-tetrahydronaphthalen]-4-one-(spiroelliptin). Spiroelliptin rearranges upon methylation to 2,2′-trimethylene-3,4,5,4′,5′-penta-methoxybiphenyl. 相似文献
7.
《Bioscience, biotechnology, and biochemistry》2013,77(10):1709-1711
For use as the internal standards in a quantitative analysis of natural jasmonic acid (JA) and methyl jasmonate (JAMe) by gas chromatography-mass spectrometry-selected ion monitoring, (±)-2-(2,3–2H2)JA and its methyl ester, (±)-2-(2,3–2H2)JAMe, were efficiently prepared from 2-(2–pentyl)-2-cyclopentenone through catalytic semi-deuteriogenation of acetylenic intermediates with deuterium gas in pyridine. 相似文献
8.
Three further compounds have been isolated from Zollernia paraensis: 2,7-dihydroxy-4′-methoxy-3-phenylcoumarin, (±)-5,7-dihydroxy-2′,4′-dimethoxyisoflavanone and the new 7,2′,4′-trihydroxy-3′-methoxyisoflavone. 相似文献
9.
2′,4′-Dihydroxychalcone, 4′-hydroxy-2′-methoxychalcone and 2′,4′-dihydroxy-3′-methoxychalcone were isolated and characterized from the resinous exudate produced by Acacia neovernicosa. Smaller amounts of isoliquiritigenin, pinocembrin and chrysin were also found and identified by their chromatographic properties and UV spectra. The material of one collection contained galangin, 3-methylkaempferol and 3,3′ -dimethylquercetin. 相似文献
10.
The new (±)-bacillipyrrole A (1) and bacillipyrazine A (2), together with seven known compounds, were isolated from a culture of the Mariana Trench sediment-derived bacterium Bacillus subtilis SY2101 in rice medium. Structures of the new compounds were elucidated by their HRESIMS data and NMR spectroscopic analyses. The known compound 3,5,6-trimethylpyrazine-2-methyl acetate (4) showed antiproliferative activity against human glioma U87MG cells with an IC50 value of 22.6 ± 2.8 μM. 相似文献
11.
4,4,6-Trimethyl-2-(3-phenylpropionyl)cyclohexane-1,3,5-trione, 2′-hydroxy-4′,6′-dimethoxy-3′-methyldihydrochalcone, 2′,6′-dihydroxy-4′-methoxy-3′,5′-dimethyldihydrochalcone and 2,2,5-trimethyl-4(3-phenylpropionyl)cyclopent-4-ene-1,3-dione, constituents of Myrica gale, have been synthesized. 相似文献
12.
13.
Maryam Gilandoust Kachigere B. Harsha Chakrabhavi Dhananjaya Mohan Ainiah Rushdiana Raquib Shobith Rangappa Vijay Pandey Peter E. Lobie Kanchugarakoppal S. Rangappa 《Bioorganic & medicinal chemistry letters》2018,28(13):2314-2319
Vascular endothelial growth factor (VEGF) and its receptor (VEGFR) is essential for physiological functions of tissues and neovasculature. VEGFR signaling is associated with the progression of pathological angiogenesis in various types of malignancies, making it an attractive therapeutic target in cancer treatment. In the present work, we report the synthesis of 1,4-disubstituted 1,2,3-triazoles and 1,2,4-triazolo[1, 5-a]pyrimidine derivatives via copper (I)-catalyzed azide-alkyne cycloaddition (CuAAC) reaction and screened for their anticancer activity against MCF7 cells. We identified 1-(2′-ethoxy-4′-fluoro-[1,1′-biphenyl]-4-yl)-4-phenyl-1H-1,2,3-triazole (EFT) as lead cytotoxic agent against MCF7 cell lines with an IC50 value of 1.69?µM. Further evaluation revealed that EFT induces cytotoxicity on Ishikawa, MDA-MB-231 and BT474 cells with IC50 values of 1.97, 4.81 and 4.08?µM respectively. However, EFT did not induce cytotoxicity in normal lung epithelial (BEAS-2B) cells. Previous reports suggested that 1,2,3-triazoles are the inhibitors of VEGFR1 and therefore, we evaluated the effect of EFT on the expression of VEGFR1. The results demonstrated that EFT downregulates the expression of VEGFR1 in MCF7 cells. In summary, we identified a potent cytotoxic agent that imparts its antiproliferative activity by targeting VEGFR1 in breast cancer cells. The novel compound could serve as a lead structure in developing VEGFR1 inhibitors. 相似文献
14.
D.R. Thakker H. Yagi H. Akagi M. Koreeda A.Y.H. Lu W. Levin A.W. Wood A.H. Conney D.M. Jerina 《Chemico-biological interactions》1977,16(3):281-300
(±)-7β,8α-Dihydroxy-9β,10β-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (diol epoxide-1) and (±)-7β,8α-dihydroxy-9α,10α-epoxy-7,8,9,10-tetrahydrobenzo[a]pyrene (diol epoxide-2) are highly mutagenic diol epoxide diastereomers that are formed during metabolism of the carcinogen (±)-trans-7,8-dihydroxy-7,8-dihydrobenzo[a]pyrene. Remarkable stereoselectivity has been observed on metabolism of the optically pure (+)- and (?)-enantiomers of the dihydrodiol which are obtained by separation of the diastereomeric diesters with (?)-α-methoxy-α-trifluoromethylphenylacetic acid. The high stereoselectivity in the formation of diol epoxide-1 relative to diol epoxide-2 was observed with liver microsomes from 3-methylcholanthrene-treated rats and with a purified cytochrome P-448-containing monoxygenase system where the (?)-enantiomer produced a diol epoxide-2 to diol epoxide-1 ratio of 6 : 1 and the (+)-enantiomer produced a ratio of 1 : 22. Microsomes from control and phenobarbital-treated rats were less stereospecific in the metabolism of enantiomers of BP 7,8-dihydrodiol. The ratio of diol epoxide-2 to diol epoxide-1 formed from the (?)- and (+)-enantiomers with microsomes from control rats was 2 : 1 and 1 : 6, respectively. Both enantiomers of BP 7,8-dihydrodiol were also metabolized to a phenolic derivative, tentatively identified as 6,7,8-trihydroxy-7,8-dihydrobenzo[a]pyrene, which accounted for ~30% of the total metabolites formed by microsomes from control and phenobarbital-pretreated rats whereas this metabolite represents ~5% of the total metabolites with microsomes from 3-methylcholanthrene-treated rats. With benzo[a]pyrene as substrate, liver microsomes produced the 4,5-, 7,8- and 9,10-dihydrodiol with high optical purity (>85%), and diol epoxides were also formed. Most of the optical activity in the BP 7,8-dihydrodiol was due to metabolism by the monoxygenase system rather than by epoxide hydrase, since hydration of (±)-benzo[a]pyrene 7,8-oxide by liver microsomes produced dihydrodiol which was only 8% optically pure. Thus, the stereospecificity of both the monoxygenase system and, to a lesser extent, epoxide hydrase plays important roles in the metabolic activation of benzo[a]pyrene to carcinogens and mutagens. 相似文献
15.
A new dihydrofuranochalcone has been identified in seeds of Psoralea corylifolia and its structure confirmed by synthesis. 相似文献
16.
Irene Domínguez-Pérez Ramiro Téllez-Sanz Isabel Leal Luis M. Ruíz-Pérez Dolores González-Pacanowska Luis García-Fuentes 《Biochimica et Biophysica Acta - Proteins and Proteomics》2004,1702(1):33-40
We have investigated the binding of 2′-deoxyuridine 5′-monophosphate (2′-dUMP) to Leishmania major deoxyuridine 5′-triphosphate nucleotide hydrolase (dUTPase) by isothermal titration microcalorimetry under different experimental conditions. Binding to dimeric L. major dUTPase is a non-cooperative process, with a stoichiometry of 1 molecule of 2′-dUMP per subunit. The utilization of buffers with different ionization enthalpies has allowed us to conclude that the formation of the 2′-dUMP–dUTPase complex, at pH 7.5 and 30 °C, is accompanied by the uptake of 0.33±0.05 protons per dUTPase subunit from the buffer media. Moreover, 2′-dUMP shows a moderate affinity for the enzyme, and binding is enthalpically driven across the temperature range studied. Besides, whereas ΔG° remains practically invariant as a function of temperature, both ΔH and ΔS° decrease with increasing temperature. The TS and TH were 23.4 and 13.6 °C, respectively. The temperature dependence of the enthalpy change yields a heat capacity change of ΔCp°=?618.1±126.4 cal·mol?1·K?1, a value low enough to discard major conformational changes, in agreement with the fitting model. An interpretation of this value in terms of solvent-accessible surface areas is provided. 相似文献
17.
Vittorio Vecchietti Giorgio Ferrari Fulvia Orsini Francesca Pelizzoni 《Phytochemistry》1979,18(11):1847-1849
A new lignan glycoside, 5-methoxy-9-β-xylopyranosyl-(-)- isolariciresinol and two indole alkaloids have been characterised from the bark of Cinnamosma madagascariensis. 相似文献
18.
《Journal of enzyme inhibition and medicinal chemistry》2013,28(3):422-429
A new bis heterocycle comprising both bioactive 2-aminopyrimidine and thiazolidin-4-one nuclei namely 3-(4′-(4″-fluorophenyl)-6′-phenylpyrimidin-2′-yl)-2-phenylthiazolidin-4-one 3 was synthesized, characterized with the help of melting point, elemental analysis, FT-IR, MS, one-dimensional NMR (1H, 13C) spectra and we evaluated the chemopreventive potential of 3-(4′-(4″-fluorophenyl)-6′-phenylpyrimidin-2′-yl)-2-phenylthiazolidin-4-one based on in vivo inhibitory effects on 7,12-dimethylbenz[a]anthracene (DMBA)-induced hamster buccal pouch carcinogenesis. Administration of 3 effectively suppressed oral carcinogenesis initiated with DMBA as revealed by the reduced incidence of neoplasms. Lipid peroxidation, glutathione (GSH) content, and the activities of glutathione peroxidase (GPx), glutathione S-transferase (GST) were used to biomonitor the chemopreventive potential of 3. Lipid peroxidation was found to be significantly decreased, whereas GSH, GPx, GST, and GGT were elevated in the oral mucosa of tumor-bearing animals. Our data suggest that 3 may exert its chemopreventive effects in the oral mucosa by modulation of lipid peroxidation and enhancing the levels of GSH, GPx, and GST. 相似文献
19.
Sheila A. Doggrell 《Chirality》1993,5(1):8-14
The effects of (±)-, (+)-, and (?)-atenolol, sotalol, and amosulalol alone on the rat left atria and portal vein and on the respective β1- and β2-adrenoceptor-mediated responses to isoprenaline have been determined. (±)-Atenolol at 10?6 M had no effect whereas high concentrations of (+)- and (?)-sotalol, 10?5–10?4 M, and (±)-, (+)-, and (?)-amosulalol depressed the response of the rat left atria to cardiac stimulation which indicates membrane stabilizing activity. None of the drugs tested had any effect alone on the rat portal vein. The order of potency as antagonists was (±)-amosulalol > (±)-atenolol > (±)-sotalol at β1-adrenoceptors and (±)-amosulalol > (±)-sotalol > (±)-atenolol at β2-adrenoceptors. (±)-Atenolol and (±)-amosulalol are β1-selective whereas (±)-sotalol is β2-selective. For each of the racemic β-blockers, the β1- and β2-adrenoceptor blocking activity was predominantly due to the (?)-enantiomer. © 1993 Wiley-Liss, Inc. 相似文献
20.
In addition to sitosterol and taraxerone, a new substituted 1,2-diarylethane, gigantol has been isolated from Cymbidium giganteum and characterized as 1-(3′-hydroxy-5′-methoxyphenyl-2-(4″-hydroxy-5″-methoxyphenyl)ethane on the basis of physicochemical data and through synthesis of its derivative. 相似文献