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1.
Summary The racemic form of homopterocarpin (V), a constituent of red sandal-wood, has been synthesized by a method which has previously been proposed by the authors. N. M. R. spectral studies in conjunction with the examination of models have enabled the assignment of thecis configuration (V) to homopterocarpin.

V. Mitteilung. IV. Mitteilung sieheH. Suginome, Exper.18, 161 (1962).  相似文献   

2.
Summary The capacity of binding copper ions of several aminoacids and peptides has been investigated. A direct colorimetric method measuring comparable values of bound Cu2+ has been developed.

37. Mitteilung; 36. Mitteilung:R. Gall undH. Erlenmeyer, Helv. chim. Acta38, 1421 (1955).  相似文献   

3.
Summary Reserpinine, a minor alkaloid ofRauwolfia serpentina Benth. accompanying Reserpine, has been isolated, and its structural formula is proposed.

10. Mitteilung über Rauwolfia Alkaloide. — 9. Mitteilung sieheF. Bader, D. F. Dickel undE. Schlittler, Amer. Soc.76 (1954) (im Druck).  相似文献   

4.
Zusammenfassung Die Struktur desAspidosperma-Alkaloids Pyrifolidin (I) wird durch Protonresonanz und durch Vergleich mit Aspidospermin und Aspidocarpin bewiesen. Dieses Alkaloid ist in seiner absoluten Konfiguration ein Antipode des Aspidospermins.

Paper XXV,C. Djerassi, A. A. P. G. Archer, T. George, B. Gilbert, J. N. Shoolery, andL. F. Johnson, Exper.16, 532 (1960).

Acknowledgement. Financial support has been provided by grant H-5048 of the National Heart Institute, National Institutes of Health (U.S. Public Health Service), and by the Conselho Nacional de Pesquisas (Brazil). The postdoctorate research fellowship ofB. Gilbert in Rio de Janeiro was financed from a grant of the Rockefeller Foundation in support of a collaborative research program between Stanford University and the Instituto de Quimica Agricola, Rio de Janeiro (Brazil).  相似文献   

5.
Summary Sodium acetate I-14C has been injected to the sea anemoneCalliactis parasitica (coelenterate,anthozoa). Sterols and squalene were found unlabelled in this experiment. An analysis of the sterol mixture is reported.

Nous remercionsMM. Cosson, Bardey etVarenne qui ont effectué les mesures de spectrométrie de masse sur un appareil AEI MS9, sous la direction du DrB. C. Das.

Nous remercions le ProfesseurE. Lederer pour l'intérêt qu'il a porté à ce travail.

Nous remercions la Station Biologique de Roscoff pour l'expédition de ces animaux.  相似文献   

6.
Summary Sodium acetate I-14C has been injected to the sea anemoneCalliactis parasitica (coelenterate,anthozoa). Sterols and squalene were found unlabelled in this experiment. An analysis of the sterol mixture is reported.

Nous remercionsMM. Cosson, Bardey etVarenne qui ont effectué les mesures de spectrométrie de masse sur un appareil AEI MS9, sous la direction du DrB. C. Das.

Nous remercions le ProfesseurE. Lederer pour l'intérêt qu'il a porté à ce travail.

Nous remercions la Station Biologique de Roscoff pour l'expédition de ces animaux.  相似文献   

7.
Summary The catalysis of H2O2 decomposition by Cu2+-complexes of RNA and DNA has been investigated. It is shown that both complexes decompose H2O2, but only the Cu2+-RNA-system shows peroxidative activity too, e.g. only in this case the nucleotide bases are degraded. Thermal denaturation of DNA also leads to a Cu2+-complex with peroxidative activity, the latter being dependent on the degree of denaturation.

V. Mitteilung:S. Petri, H. Sigel undH. Erlenmeyer, Helv. chim. Acta49, 1778 (1966).

12. Mitteilung überMetallionen und H 2 O 2; 11. Mitteilung:H. Ch. Curtius, P. Anders, R. Zell, H. Sigel undH. Erlenmeyer, Helv. chim. Acta49, 2256 (1966).  相似文献   

8.
Summary Twenty-one alkaloids have been identified from the root ofRauwolfia ligustrina R. & S. The more important ones are reserpine, pseudoreserpine and raugustine, a new base which is isomer to pseudoreserpine. The structure of the latter compound is discussed.

Mitteilung über Rauwolfia-Alkaloide

Mitteilung sieheC. F. Huebner undE. Schlittler, J. Amer. chem. Soc.79, 250 (1957).  相似文献   

9.
Summary The incorporation of tyrosine-2-14C-15N into xanthocillin X (I) byPenicillium notatum Westling has been investigated showing that nitrogen of the isocyano groups originates from tyrosine, which is incorporated as C6-C2-N-unit.

1. Mitteilung:H. Achenbach undH. Grisebach, Z. Naturforsch.20b, 137 (1965).  相似文献   

10.
Summary Ser4-Glu(NH2)8-Oxytocin has been synthesized. The identity of the synthetic compound with the neurohypophysal hormone (Glumitocin) recently isolated from species of cartilaginous is demonstrated.

Über Peptidsynthesen XLIII. Mitteilung,E. Klieger, Experientia23, 620 (1967).  相似文献   

11.
Summary A yellow flavonoid pigment, which occurs as a companion of the lignan glycosides inPodophyllum peltatum L. andP. emodi Wall. has been identified as astragalin (=kaempferol-3-glucoside).

18. Mitt. über mitoschemmende Naturstoffe. 17. Mitt.:E. Schreier, Helv. chim. Acta47, 1529 (1964).  相似文献   

12.
Summary A strain ofStreptomyces contains a mixture (ca. 3:1) of 2d-hydroxy-12l-methyltetradecanoic and 2d-hydroxy-13-methyltetradecanoic acids; it has the same properties as a similar mixture prepared by synthesis.

11e Communication sur la chimie des micro-organismes; 10e communication:C. Lacave, J. Asselineau etR. Toubiana, Europ. J. Biochem.2, 37 (1967).  相似文献   

13.
Summary The triazine herbicides are potent inhibitors of theHill reaction, resembling the phenylureas, acylanilides and carbamates. The inhibition of the photosynthesis by the triazines is the most obvious explanation for their mode of action in plant metabolism. Besides this there are also effects on light independent reactions where the effective concentrations are higher than those inhibiting the photosynthesis. Particularly, a positive influence of the triazines on the uptake of the nutrients by the roots was noted. Changes in the nitrogen metabolism of the plants, due to increased uptake of nitrate from the medium, result in a higher content of organic nitrogen in the plants.Several enzyme systems in plants and in micro-organisms are influenced by the triazine herbicides. Until now, the mechanism of action has not been elucidated.Concerning the phenomenon of the selectivity of the triazine herbicides, several factors may be responsible. The different abilities of the plant species to metabolize the herbicide and to translocate it to the active centres in the cells are significant from the biochemical point of view.

Une partie de ce travail a été présentée lors de la 463e séance de la Biochemical Society, Aberystwyth, septembre 1966.P. W. Müller, Biochem. J.101, 1P. (1966).Nous tenons à exprimer nos remerciements àR. Truan qui a bien voulu se charger de la version française ainsi qu'àG. Dupuis pour sa participation à la mise au point du manuscrit.  相似文献   

14.
Résumé L'examen cytologique de la descendance de 2Xenopus borealis révéla 50% d'individus dotés de noyaux à 1 et 2 nucléoles (situation normale) et 50% à 1, 2 et 3 nucléoles. Le caryotype de ces derniers démontra la présence de 3 organisateurs nucléolaires, au lieu de 2, l'origine de l'élément supplémentaire relevant d'une translocation réciproque entre 4 et 7.

Supported by a grant (No. 3.60.68) from the Fonds national suisse de la Recherche Scientifique and the George and Antoine Claraz donation.

Unpublished research in this laboratory has shown thatXenopus laevis borealis (Parker) is a species on its own right and we propose to name itXenopus borealis (Parker).

Material collected byFischberg andKobel, who express their gratitude to the Fisheries and Game Dept. of Kenya for permission to collect frogs of the genusXenopus.

Acknowledgments. The authors wish to thank Mrs.J. Tymowska and MissE. Ackermann for their technical advice; they are grateful to Mr.J. Jackson, MissM. C. Payot, MissL. Ricard and Mr.P. Grutter for their assistance and useful help.  相似文献   

15.
Summary Condensation of benzil with two monosubstituted guanidines in the presence of 50 mol% of potassium hydroxide leads to the formation of 2-(subst. imino)-4, 4-diphenyl-imidazolidin-5-ones (Ia, b); by reduction of the potassium hydroxide used the formation of these products is more or less driven back in favour of the formation of 3-substituted 5, 5-diphenyl-glycocyamidines (Ic, d). A possible explanation for these orientation phenomena is given.

5. Mitteilung über Hydantoine, Thiohydantoine und Glykocyamidine2.

4. Mitteilung sieheK. Lempert undJ. Breuer Chem. Ber.92, 1710 (1959).  相似文献   

16.
Summary The mechanism of incorporation of different mental ions into phthalocyaninetetrasulfonic acid in aqueous solution has been investigated. It was found that the rate of the reacion with Cu2+ depends on the dissociation rate of the N-H-bond of this porphyrin-like chelating agent, whereas the reaction rate with other metal ions, like Zn2+, does not.

II. Mitt. Siehe I. Mitt.:K. Bernauer undS. Fallab, Helv.44, 1287 (1961).

Herrn Prof. Dr.H. Erlenmeyer sind wir für sein reges Interesse an dieser Arbeit zu bestem Dank verpflichtet.  相似文献   

17.
Summary The most important facts and conceptions regarding the mechanism of blood coagulation, supplemented by our own as yet unpublished findings, are represented in a schematically simplified Table. The process of co-agulation is subdivided into five phases, i.e. the prephase (vasoconstriction, agglutination), the first principal phase (formation of thromboplastin), the second principal phase (formation of thrombin), the third principal phase (formation of fibrin), as well as a post-phase (retraction, fibrinolysis). In this new scheme, recently discovered clotting factors and the various inhibitors could easily be incorporated into the classical picture of Morawitz. The scheme is explained briefly.

9. Mitteilung über Probleme der Blutgerinnung.—8. Mitteilung sieheR. Marbet undA. Winterstein, Die Medizinische1954, 877.  相似文献   

18.
Summary The chloride electrochemical potential difference between the inside of cells ofNitella translucens and some external solutions, where Cl has been progressively replaced by benzenesulphonate, has been measured by means of Ag-AgCl electrodes. It appears that benzenesulphonate moves into the cell by an electrogenic pump and that the uptake of Cl byNitella is not in contradiction with a carrier hypothesis.

This work was supported by grants from the F.N.R.S. and was carried out in the Biophysics Section of the Edinburgh University. We are indebted to Dr. E. J.Williams and Dr.Hogg for having sponsored this research and kindly provided the material.  相似文献   

19.
Summary Reference is made to a treatise published in 1756 byJoseph Black (1728–1799), which was the first work to contain conclusive evidence of a gas bound to solid bodies; and in this connection the historical significance of the earliest studies on carbon dioxide is emphasised. Attention is drawn in particular to a subject about which little has hitherto been known,i.e., the use whichBlack and his contemporaries (notablyDavid Macbride) made of this discovery by applying it to animal and human physiology.

Eine ausführlichere Würdigung dieses geschichtlichen Sachverhalts erscheint in Gesnerus (Schweiz)1956, Heft 3/4.  相似文献   

20.
Zusammenfassung Aus den Wurzeln vonArnebia nobilis wurden 4 antibiotisch wirksame Stoffe isoliert. Die Struktur von dreien wurde aufgeklärt.

On deputation from the Chemistry Department, Lucknow University.

To whom enquiries should be made. The isolation of shikonin monoacetate and,-dimethylacrylate fromLithosperm erythrorhizon, I.Morimoto, T.Kishi, S.Ikegana and Y.Hirata, Tetrahedron Lett.4737 (1965), has been brought to our notice since communicating this paper.

Communication No. 1305 from the Central Drug Research Institute.  相似文献   

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