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1.
Summary The structures of 2 new polyhydroxylated cannabinoids, (±)9, 10-dihydroxy- 6a(10a)-tetrahydorcannabinol and (±)8, 9-dihydroxy- 6a(10a)-tetrahydrocannabinol, obtained from a hexane extract of an IndianCannabis variant were determined by spectral means and correlation with cannabinol.Acknowledgments. Supported by contract No. HSM-42-70-109 from the National Institute on Drug Abuse and the Research Institute of Pharmaceutical Sciences, School of Pharmacy, University of Mississippi. The authors are grateful to Mrs Glenda Lewis (Research Institute) for running the gas chromatographic analyses and to Mr C. Versluis (Analytical Chemistry Laboratory, University Of Utrecht, The Netherlands) for recording an element list of both compounds.Cannabis Herbarium specimens are stored in the herbarium, Department of Pharmacology, School of Pharmacy, University of Mississippi, University, MS 38677, USA.  相似文献   

2.
Summary A novel sesquiterpene lactone, 9--hydroxyparthenolide (1) was isolated from a chloroform extract ofAnvillea garcini that was collected in Iran. The structure of1 was assigned on the basis of high field NMR decoupling experiments and other spectroscopic evidence. This -methylene lactone has shown significant activity in both the 9KB cell culture and P388 mouse leukemia test systems.The authors acknowledge the support of contract No. N01-CM-97296 from the National Cancer Institute and the use of the Purdue University Biochemical Magnetic Resonance Laboratory (NIH grant No. RR01077). This is paper 16 in the series Potential Antitumor Agents.  相似文献   

3.
Summary -(4-chlorophenyl)-GABA (Baclofen, Lioresal antagonized the excitant actions of acetylcholine and substance P to comparable extents.L-glutamate-induced excitation was affected to a lesser extent These findings do not support the suggestion that -(4-chlorophenyl)-GABA is a specific substance P antagonist.Acknowledgments. The author is indebted to Ciba-Geigy (Canada) Ltd. for a gift of -COPG.Brenda Robson provided technical assistance. This work was supported by grants from the CanadianM. R. C. and the university of Saskatchewan.  相似文献   

4.
Summary -L-aspartyl-L-alanine, a dipeptide found in the brain, increases the amplitude of the miniature endplate potentials (MEPPs) in phrenic nerve-diaphragm preparations from rats. The peptide also stimulates the appearance of a population of giant MEPPs.This work was supported by NSF grant BNS 79-00352 and NIH grant CA-27031 to R. Lim.  相似文献   

5.
Summary Cyanidin-3--glucoside was shown to be an important factor of resistance in cottonGossypium hirsutum L. leaves to the tobacco budwormHeliothis virescens (Fab.). This provides a potential basis for achieving insect resistance in non-glanded cotton and other crops infested byHeliothis.In cooperation with the Mississippi Agriculture and Forestry Experiment Station, Mississippi State. Mention of a trademark, proprietary product or vendor does not constitute a guarantee or warranty of the product by the U.S. Department of Agriculture and does not imply its approval to the exclusion of other products or vendors that may also be suitable.  相似文献   

6.
Summary (E)-3-Formylbut-2-enenitrile (4) is synthesized in 2 steps by reacting pyruvaldehyde dimethylacetal and acetonitrile in the presence of sodium methoxide, followed by acid hydrolysis to give 58% overall yield on distillation. The aldehyde4 can be stepwise and selectively reduced to (E)-3-hydroxymethylbut-2-enylamine (7a) in 37% total yield or exhaustivelyb reduced in 1 step to (±)-4-hydroxy-3-methylbutylamine (6) in 46% total yield. Compound7a and6 can be condensed with 6-chloropurine to give zeatin and (±)dihydrozeatin respectively. This provides a readily accessible method for isotope-labelled zeatin and its derivatives at side chain.Contribution No. 1064, Alberta Research CouncilProcess for the Preparation oftrans-3-formylbut-2-enenitrile S. Chen and J. MacTaggart, patent applicatioin registered in Canada and the United States of America.Acknowledgment. The author thanks Mr J. M. MacTaggart and Mrs C. M. Goulet for valuable experimental assistance and Dr R. M. Elofson for helpful discussions.  相似文献   

7.
Zusammenfassung An Glukorons?ure gebundenes 1-(3′-Methoxy-4′-hydroxy-phenyl)-6, 7-dimethoxy-chinolin ist als Metabolit des Papaverins beim Menschen und bei S?ugetieren erkannt und isoliert worden. Ein in den Lebermikrosomen enthaltenes Ferment, dassauerstoff-und TPNH-abh?ngig ist, bewirkt die Methoxylspaltung, und ein weiteres Ferment übertr?gt die Glukurons?ure aus ihrer Verbindung mit Uridinphosphat auf die entstandene phenolische Verbindung.   相似文献   

8.
修正的Kleene系统中的Σ-(α-重言式)理论   总被引:12,自引:1,他引:11  
证明了关于全体赋值而言 ,修正的Kleene系统中只有 3种α 重言式 .在赋值域为有限集的情形证明了当α过半时α 重言式的类类互异定理 .最后 ,在有限值系统中证明了广义重言式的重言式表示定理 .  相似文献   

9.
Summary N-(5-Phosphopyridoxyl)-4-aminobutyric acid, a stable adduct of pyridoxal phosphate and 4-aminobutyric acid, has been shown to be a potent inhibitor of rat brain 4-aminobutyric acid aminotransferase (GABA-T) with a Ki of 1.4 M.Acknowledgments. This work was supported in part by the United Parkinson Foundation, l'Association Canadienne l'Ataxie de Friedreich, and the Medical Research Council of Canada.  相似文献   

10.
Summary The profile of action in animals of CQP 201-403, a novel 8-amino-ergoline, is in most aspects that of a very potent dopaminomimetic, both as a prolactin secretion inhibitor, and at the levels of the CNS and the cardiovascular system. Qualitatively CQP 201-403 differs slightly from bromocriptine and apomorphine in its effects on the CNS (no influence on serotonin metabolism in the rat cortex; induction of masculine mounting behavior in rats) and the cardiovascular system of the dog (reflex tachycardia in response to a blood-pressure fall). In man the new compound proved to be highly active in lowering prolactin serum levels and to be more potent than bromocriptine (Parlodel®).In memory of Dr Annemarie Closse, who died 14 June 1987.  相似文献   

11.
Summary Clausarin (1), a novel coumarin, has been isolated along with methyl linolenate, dentatin, clausenidin, -sitosterol and heptaphylline from the roots of Clausena pentaphylla. Based on spectroscopic evidence, its structure has been established as 3, 10-bis (1, 1-dimethylallyl)-8, 8-dimethyl-5-hydroxy-2H, 8H-benzo (1, 2-b5, 4-b) dipyran-2-one.  相似文献   

12.
Zusammenfassung Bei chinesischen Hamstern aus Inzuchten mit erblicher Zuckerkrankheit wurden erhöhte Serum--2-Eiweisswerte konstatiert. Die Erhöhung erfolgt vor Auftreten der Hyperglykämie oder Blutgefäss- und anderen sekundären pathologischen Veränderungen. Es wird gefolgert, dass die Eiweisserhöhung gen-bedingt ist und wahrscheinlich chemisch abnormales Eiweiss betrifft.

This investigation was supported in part by research grants from the National Institutes of Health, USPHS #E1560 and #CY3335, the National Science Foundation (#6-9602), and the Damon Runyon Memorial Fund (#293).  相似文献   

13.
Summary A new sesquiterpene alcohol, 12-hydroxy-E--bisabolene, is reported from an undescribed Caribbean sea whip of the genusPseudopterogorgia. The structure of this new alcohol was established based upon spectral analyses and through chemical interconversions.Acknowledgment. This research was supported by NOAA, Office of Sea Grant, Department of Commerce, under grant NA80AA-D-00120, and in part by the California State Resources Agency, project R/MP-22. The U.S. Government is authorized to reproduce and distribute reprints. We wish to acknowledge the mass spectral support provided by the Bioorganic Biomedical Mass Spectrometry Resource Center, University of California, San Francisco (A.L. Burlingame, Director) which is supported through NIH grant RR00719.  相似文献   

14.
Summary A new series of O-glycosyl enkephalins has been prepared, following a convergent strategy, with high chemical yields. The galactosyl analogue,O 1.5-(-D-galactopyranosyl) [DMet2, Hyp5] enkephalin amide proved to be one of the most potent in vivo opioid agonists synthesized up to now.  相似文献   

15.
Summary In synthesizing 6-(4-pyridyl)-3-mercapto-1,2,4-tria-zin-5-one from the oxime of 4-pyridyl-glyoxylic acid, isonicotinaldehyde-thiosemicarbazone is obtained through decarboxilation as a by-product, which is mainly responsible for the tuberculostatic properties.  相似文献   

16.
苯并(a)芘的环境污染、健康危害及研究热点问题   总被引:30,自引:0,他引:30  
本文主要介绍了多环芳烃类中致癌性最强的化合物之一-苯并(a)芘对人体健康的危害,污染来源和程度,环境质量和污染排放标准,以及目前的科研热点问题。  相似文献   

17.
Summary The cells of heterogametic females with ZW sex chromosomes express H-Y or H-W antigen. A hypothesis is formulated to explain why these animals are capable of practicingamphigonia retardata, i.e. delay in actual fertilization of eggs by retaining viable sperm within the oviduct for a considerable time (several months).  相似文献   

18.
对一类简单一维平板液-固相变过程进行了研究,在过程总时间一定的条件下,以过程的(火积)耗散最小为优化目标,应用最优控制理论导出了外界热源温度随时间变化的最优规律,得出了对应于相变过程耗散最小最优换热策略下的(火积)耗散为恒温换热策略下的(火积)耗散的8/9,且与系统其它参数无关的结论.给出了数值算例,并与传统的恒温换热策略和熵产生最小最优换热策略进行了比较.本文研究结果对实际液-固相变过程最优换热策略的选取具有一定的理论指导作用.  相似文献   

19.
提出了由模糊子集生成的(λ,T)-模糊理想(滤子)的概念,并且用三角范数的性质及生成理想的概念刻画了(λ,T)-模糊理想(滤子)。研究了由模糊集生成的(λ,T)-模糊理想的逆像在同态映射下与模糊集的逆像生成的(λ,T)-模糊理想是相等的。  相似文献   

20.
An early example is von Neumann's and Charney's Princeton Meteorological Project in the period 1946–53 which ended with daily numerical prediction in less than 2 hours. After this stage, the questions of long-range forecasting and general circulation of the atmosphere became of greater importance. The late 1950s saw the emergence of an alternative: were atmospheric models used mainly for prediction or understanding? This controversial debate in particular occurred during an important colloquium in Tokyo in 1960 which gathered together J. Charney, E. Lorenz, A. Eliassen, and B. Saltzman, among others, and witnessed discussions on statistical methods for predictions and/or maximum simplification of dynamic equations. This phase ended in 1963 with Lorenzs seminal paper on “Deterministic non periodic flows.” (Received February 11, 2000)  相似文献   

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