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1.
Zusammenfassung Axillarin (5, 7, 3, 4-Tetrahydroxy-3,6-dimethoxyflavon). 5,3,4-Trihydroxy-3,6,7-trimethoxyflavon und 5,7,3,4-Tetrahydroxy-3,8-dimethoxyflavon wurden synthetisiert.  相似文献   

2.
Zusammenfassung Die Injektion von N6-2-O-Dibutyryl-adenosin-3 5-monophosphat in den lateralen Hirnventrikel von Kaninchen führt zu einer langanhaltenden Fieberreaktion, was vermuten lässt, dass zyklisches Adenosin-35-monophosphat als weiterer Mediator in der Genese des Fiebers fungiert.  相似文献   

3.
a aaa a aa aa a a E. coli aa, a aa aa a , a a aa - a .

Laboratory of Biological Investigations.

Laboratory for Chemistry of Antibiotics.  相似文献   

4.
Die Induktion lysogener Bakterien durch Nitrosamide   总被引:1,自引:0,他引:1  
Summary N, N-dinitroso-N, N-dimethyloxamide and N, N-dinitroso-N, N-dimethylterephtal acid amide, both mutagenic for yeast cells, induce phage production by lysogenicEscherichia coli K12 () cells.  相似文献   

5.
Two pteridine-containing bromophysostigmine alkaloids, urochordamine A and B, which were isolated from ascidians as larval metamorphosis promoters, were converted to more polar compounds, urochordamine A and B, respectively, when left standing in protic solvents. These four compounds promoted larval metamorphosis of the ascidianHalocynthia roretzi in the order A>A>B>B, and induced metamorphosis of the pediveliger larvae of the musselMytilus edulis galloprovincialis.  相似文献   

6.
- . Ovis musimon (2n=54) O. orientalis (2n=54) - - -O. canadensis mexicana (2n=54) O. musimon x O. canadensis 12 - . 2 27 . - .

Supported by National Science Foundation Grant no. GB 32114X and the Sprague Foundation. We thank Dr. T. C. Hsu for assistance in making the chromosome preparations and for advice and encouragement. The Trustees of the Rachelwood Wildlife Research Preserve generously allowed the biopsy of specimens of their custody. Mr.Arthur Popham kindly provided the specimens from Iran while Dr.R. M. Robinson obtained biopsies from the desert sheep.  相似文献   

7.
Zusammenfassung Die Synthese von Toxicarol Isoflavon (2, 2-Dimethylpyrano(6, 5: 7,8)-5-hydroxy-2,4 5-trimethoxyisoflavon) aus 2,2-dimethyl-5-hydroxy-7-methoxychroman wird beschrieben.  相似文献   

8.
Summary Extracts of the marine spongeAxinella polycapella contain 1,2,4-trihydroxybenzene (1) and 2,2,4,4,5,5-hexahydroxybiphenyl (3) as antimicrobial constituents. Methods of synthesizing3 by, oxidative dimerization of1 were examined.Acknowledgment. We are grateful to Dr Klaus Reutzler for identifying the sponge and one of us (SW) is pleased to acknowledge fellowship support (1-F32-AI_05883-02) from the Public Health Service.  相似文献   

9.
Summary Incubation of 5,5-7,7-tetramethoxy-8,8-biflavone withAspergillus niger results in the formation of 4,4-dihydroxy-5,5-7,7-tetramethoxy-8,8-biflavan.Part of this work was done at Allahabad University, Chemical Laboratories.  相似文献   

10.
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   

11.
    
Riassunto Gli autori hanno studiato l'inibizione dellal-glutamina-d-fruttosio-6-fosfato amidotransferasa per 5-nucleotidi in estratti crudi di cartilagine di pollo. L'inibizione per 5-adenilato e altri 5-nucleotidi segue una cinetica competitiva. Il 2- e 3-adenilato, così come il ribosio 5-fosfato non sono inibitori. Gli autori prospettano una possibile participazione nelle regolazione della sintesi degli aminozuccheri.  相似文献   

12.
Zusammenfassung Die Behandlung von 8-5-Anhydro-8-mercapto-2-o-mesylguanosin mit (1,2 Äquivalent) Tributylammonium-uridylat in siedendem DMF lieferte das Dinucleosidphosphat Uridyl-(3-5)-8-mercapto-2-o-mesylguanosin. Weitere Behandlung mit Raney Ni führte zum Uridyl-(3-5)-2-o-mesylguanosin.  相似文献   

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17.
1--8- () -3- () . []:[]<10:1 140 000 3±1 5×10–5 . , i 5×10–5 –6×10–5 M. , .  相似文献   

18.
Summary By oxidative degradation of capsorubin, it could be demonstrated that the methyl groups are in position 1, 1, 5 (1, 1, 5) and the OH-group is attached to carbon atom 3 (3). An analogous structure may be assumed for capsanthin and cryptocapsin.  相似文献   

19.
Summary The synthesis of 3-acetoxy-16, 20-dihydroxy-4-methyl-18-nor-5, 14-pregnano[13,14-f]hexahydro-1, 4-oxazepin-3-one (20a) is described.  相似文献   

20.
Summary A new chalcone glucoside has been isolated from the flowers ofAcacia dealbata and shown to be 4,2,4,6-tetrahydroxy-3-methoxychalcone 2-O--D-glucoside (1) by chemical degradations and spectroscopic methods. Cernuoside (4,6,3,4-tetrahydroxyaurone 4-O--D-glucoside), (2) has also been found in this plant material.Acknowledgments. The author thanks Prof. H. Wagner, Institut für pharmazeutische Arzneimittellehre der Universität München, for a sample of homoeriodictyol, and Prof. J.B. Harborne, University of Reading, for a sample of aureusidin.  相似文献   

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