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1.
Summary The 3,3,4,4-tetrahydroxy-2,2-bipyridyl-N-oxide has been synthesized by dealkylation of the corresponding tetramethyl derivative. The chemical properties of this compound are identical to those reported for the minor fungal toxin ofCortinarius orellanus, orellinine.This work is part of the Tesi di Laurea of Miss Cinzia Pierucci.  相似文献   

2.
Riassunto Un nuovo pigmento feomelanico, denominato tricosiderina B, è stato isolato dalle piume di pollo di razza New Hampshire. Sulla base delle proprietà chimiche e spettrali a tale pigmento, C23H20N4O9S2, è stata assegnata la struttura 2,2-bibenzotiazinica IV.

This work was supported by a grant from Laboratorio per la Chimica e Fisica di Molecole di Interesse Biologico del C.N.R., Napoli.  相似文献   

3.
Enterocytes isolated from rat jejunum were tested for the existence of a Cl/HCO 3 exchange, previously evidenced in basolateral membrane vesicles but not in brush border. Cells were found to retain functional integrity and transport capabilities long enough to allow Cl fluxes to be measured. Both efflux and uptake experiments indicate that a Cl/HCO 3 antiport, inhibited by 4,4-diisothiocyanostilbene-2-2-disulfonic acid (DIDS), is functional under resting conditions.  相似文献   

4.
Summary The mycotoxin alternariol (3,4,5-trihydroxy-6-methyldibenzo [a] pyrone) but not alternariol monomethyl ether (3,4-dihydroxy-5-methoxy-6-methyldibenzo [a] pyrone) is phototoxic toEscherichia coli in the presence of near UV light (320–400 nm). The phototoxicity bioassays with a DNA repair-deficient mutant ofE. coli suggested that DNA may be the molecular target for photo-induced toxicity of alternariol. Interactions between alternariol and double-stranded, supercoiled DNA suggest that alternariol interacts with DNA by intercalation. No DNA breakage was detected in this system; however, alternariol forms a complex and cross-links double-stranded DNA in near UV light. These results suggest that alternariol is a new phototoxic, DNA-intercalating agent and is a DNA cross-linking mycotoxin in near UV light.Acknowledgment. Dr Albert Stoessl (Agriculture Canada, London, Ontario, Canada) generously provided a mixture of alternariol and alternariol monomethyl ether, and made many helpful suggestions. Dr Ashwood-Smith (University of Victoria, Victoria, British Columbia, Canada) kindly supplied the microorganisms through Dr G.H.N. Towers (University of British Columbia, Vancouver). We gratefully acknowledge the gifts. It is a pleasure to acknowledge the able assistance of Mr S. Tallevi.  相似文献   

5.
Ecdysteroids in diapause eggs of the silkworm,Bombyx mori, were analyzed using high-performance liquid chromatography (HPLC) combined with radioimmunoassay (RIA). A relatively large amount of an unidentified free ecdysteroid and its phosphoric ester (conjugated form) were detected. These two compounds were isolated by a combination of column chromatography on silicic acid, thin-layer chromatography (TLC), and HPLC using a reverse-phase (RP) column. The purified compounds were identified as 3-epi-22-deoxy-20-hydroxyecdysone (22d20E) and 3-epi-22-deoxy-20-hydroxyecdysone 2-phosphate (22d20E2P) by means of mass spectrometry and nuclear magnetic resonance spectroscopy. to our knowledge, this is the first report of 22d20E and 22d20E2P.  相似文献   

6.
    
Summary Synthesis of 2,2-diphenylene chlorophosphonate and 2,2-diphenylene chlorothiophosphonate is described through the interaction of 2,2-dihydroxybiphenyl with phosphoryl chloride and thiophosphoryl chloride respectively. These compounds were screened for their fungicidal activity.  相似文献   

7.
Summary 3, 5-Dichloro-2,4-dihydroxybenzanilide, an inhibitor of histidine decarboxylase, inhibited skin tumor promotion induced by 12-O-tetradecanoylphorbol-13-acetate in mice.Acknowledgments. The authors wish to thank Miss H. Iwami for technical assistance and members of the Central Research Laboratory of Sanraku-Ocean Co., Ltd for supplying lecanoric acid analogues. This work was supported in part by the Grantsin-Aid for Cancer Research from the Ministry of Education, Science and Culture and the Ministry of Health and Welfare of Japan.  相似文献   

8.
Summary Ring fission ofp, p-DDT was studied in the rat following a single oral dose of 0.74 mg/kg (1.04 Ci) of uniformly ring-labeled14C-DDT. Expired air was passed through a solution of ethanolamine-ethylene glycol monomethyl ether (12) to trap14CO2. A total of 1.6% of the radioactivity administered was recovered in the expired air collected continually for 10 days, indicating that while degradation of the phenyl moiety is not a major route pfp, p-DDT metabolism in the rat, it is equal to the urinary excretion. Nevertheless, these results represent the most radical change accomplished in vivo of a residual insecticide yet reported in mammals.Acknowledgment. We acknowledge the secretarial work of Ms.Elaine Smolko. This study was supported by NIH fellowship No. 1 F22 ES01723-01 and No. HL16264.  相似文献   

9.
Zusammenfassung Es wird gezeigt, dass 3–5-cAMP (10–3 M) und Theophyllin (10–4 M) die Permeabilität derjenigen Lysosmen-Membranen steigern, die aus Rattenleberzellen in bezug auf saure Phosphatase and in bezug auf -Glucuronidase-Enzyme präpariert wurden.  相似文献   

10.
Summary During the development of anthers inTulipa cv. Apeldoorn the following chalcones were isolated: 2, 3, 4, 4, 6-pentahydroxychalcone as the main component and 2, 4, 4, 6-tetrahydroxy-3-methoxychalcone as well as 2, 4, 4, 6-tetrahydroxychalcone in a very small amount.

Die Untersuchungen wurden mit Mitteln der Deutschen Forschungsgemeinschaft unterstützt.  相似文献   

11.
Summary The effect of potassium ions on the formation of adenosine 3,5-monophosphate (cAMP) in the rat cerebral cortex in vivo was studied under conditions where development of spreading depression had been blocked by pretreatment of the cerebral cortex by topically applied magnesium ions. A linear relationship between potassium concentrations applied to the cortical surface and levels of cAMP has been found. Moreover, potentiation of the K+-effect by magnesium ions has been observed.  相似文献   

12.
Summary An acidic fraction of Panamenian variant ofCannabis sativa L., afforded upon repeated chromatography a new non-cannabinoid phenol {5-hydroxy-7-methoxy spiro-(cyclohexane-1, 1-indan)-4-one}Ia, named iso-cannabispiran.Acknowledgment. Supported in part by NIDA contract No. 271-78-3527 and by the Research Institute of Pharmaceutical Sciences.  相似文献   

13.
Zusammenfassung Nach Eingabe vontrans-Stilben bei Ratten wurden die grössten Mengen im Harn als 3,4,4-Trihydroxystilben, 3,4,4-Trihydroxybibenzyl und 3,3, 4,4-Tetrahydroxybibenzyl nachgewiesen. Die Bibenzylderivate werden nachscheinlich nach Ausscheidung in der Galle von Darmbakterien metabolisiert.  相似文献   

14.
Summary Anti-Fusarium oxysporum f. sp.carthami activity of 2,2,4-tri-hydroxybenzophenone was evaluated. Pretreatment with the benzophenone offered complete protection to safflower seeds and seedlings, and recovery of the latter from the fungal infection.  相似文献   

15.
Summary A new synthetic phenyl-ethyl-amine derivative, the 2-[N- (3, 4-methylen-dioxyphenylethyl)-methylaminomethyl]-tetrahydrofuran, No. 11 081, exhibits a strong protective effect against cardiac fibrillation and arrhythmias produced by various experimental methods: against fibrillation due to aconitine 3 × 10–8 on the isolated cat's heart, it is active in a concentration of 10–6–2 × 10–6. Against cardiac arrhythmias produced in the cat by adrenaline + CHCl3 or cyclopropane, it shows a protective effect by 5–10 mg/kg i.v. and even perorally by 50 mg/kg. In these tests, the antifibrillatory activity of the new compound seems to be roughly the same as that of -fagarine, and higher than that of procaine.

9e communication sur les dérivés des alcoylène-imines; 8e communication, cf. Exper.10, 261 (1954).  相似文献   

16.
Summary A blue carotenoprotein from the crayfishProcambarus clarkii was extracted and purified. This carotenoprotein contains the carotenoid astaxanthin as a prosthetic group. In the present work we have identified by reconstitution, after removing the native carotenoid, some characteristics of the carotenoids that could bind to the apoprotein. The carotenoid must have two oxo groups at positions 4, 4 and two hydroxyl groups at positions 3, 3 the hexagonal or pentagonal end structure being indifferent. It has been proved that changes in the polyene chain structure such as triple bonds destroy this binding capacity.  相似文献   

17.
Zusammenfassung Uridylyl-(3–5)-adenosin und Uridylyl-(3-5)-ionosin wurden durch Umsetzung eines passenden 5-chloro-5-deoxy-2, 3-O-isopropylidene-Nukleosids mit Uridin-3-phosphat synthetisiert.  相似文献   

18.
Summary BacteriaVibro sp. isolated from the spongeDysidea sp. were shown to biosynthesize brominated diphenyl ethers. We identified one of the bacterial brominated metabolites using gas liquid chromatography and mass spectrometry to compare this product with standard 3,5-dibromo-2-(3,5-dibromo-2-methoxyphenoxy)phenol. The latter has been isolated from ethanol extracts of the spongeDysidea sp.  相似文献   

19.
Zusammenfassung Nachweis, dass Ftorafur, N1-(2-Furanidyl)-5-Fluorouracil das Überleben leukämischer Mäuse deutlich steigert und ausserdem als Lysosomen-Stabilisator wirken könnte, wobei die in vivo Stabilisierung der Lysosomen den antileukämischen Effekt dieses Zytostatikums unterstützen könnte.  相似文献   

20.
Summary Studies of the interaction between vinblastine-like alkaloids and their receptor, i.e. tubulin, are reported. They shed some light on the structure-activity relationships in this medicinally important series: the configurations at C14 and C16 as well as the presence of the methoxycarbonyl group on C16 seem to play an essential role in the determination of biological activity.This work was supported by CNRS (A.T.P. No 3232).We thank Dr D. Pantaloni for interesting discussions, Drs N. and Y. Langlois for discussions and for supplying synthetic material, and Eli Lilly Laboratories for gifts of vinblastine, vincristine and leurosidine.  相似文献   

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