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1.
Summary -Asp1-Angiotensin II had a more pronounced action on the blood pressure of nephrectomized rats than the corresponding-compound.-Asp1-Angiotensins were more slowly destroyed by rat serum, rat kidney homogenate, and human plasma than-compounds, especially-Asp1-Angiotensin II amide.  相似文献   

2.
    
Zusammenfassung Behandlung von 1-o-Acetyl-2,3,5-tri-o-benzoyl--d-ribofuranosid mit Bortrifluorid-ätherat gibt ein Diribosid-hexabenzoat, welches zu reinem, kristallinem-d-Ribofuranosyl--d-ribofuranosid hydrolysiert werden kann.

On leave at the Eidg. Technische Hochschule, Zürich (Switzerland).  相似文献   

3.
Summary Uptake ofd-glucose anomers by isolated rat retina was studied. After 3 min incubation at 37°C in the presence of or anomer (750 g/ml), a significantly greater uptake (1.32 mg/g wet tissue) of -anomer was observed compared with that of -d-glucose (1.11 mg/g wet tissue). This result and other data suggest that the carrier ford-glucose transport in the retina prefers the -anomer stereospecifically.Acknowledgment. The authors are grateful to Mr S. Suzuki for his technical assistance.  相似文献   

4.
Summary 1--d-arabinofuranosylcytosine-5-triphosphate and 9--d-arabinofuranosyladenosine-5-triphosphate were found to have no inhibitory potency for both mammalian DNA-dependent RNA polymerase II andE. coli DNA-dependent RNA polymerase.  相似文献   

5.
Riassunto Si descrive la sintesi dei due dipeptidi isomeri acido N-acetil--l-aspartil-l-glutammico (I) e acido N-acetil--l-aspartil-l-glutammico (II). Il loro confronto con il NAAGA, dipeptide precedentemente isolato dal tessuto nervoso di alcuni mammiferi, ha dimostrato l'identità del nuovo metabolita con il-dipeptide (II).  相似文献   

6.
Summary Starting from 17-hydroxy-17-hydroxymethyl-4-androsten-3-one, we synthesized 4-chloro-17-hydroxy-17-hydroxymethyl-4-androsten-3-one-17, 20-acetonide and 17-hydroxy-17-hydroxymethyl-1, 4-androstadien-3-one. 11, 17-dihydroxy-17-hydroxymethyl-4-androsten-3-one was obtained from cortisone via methyl-17-hydroxy-3, 11-dioxo-4-etienate.  相似文献   

7.
Summary The new methods for the production of 19-norsteroids described involve the conversion of 5-halogen-6-hydroxy-steroids into the corresponding 5-halogen-6:19-ethers either with lead tetraacetate or by the hypoiodite reaction8,10. The 6:19-oxygen bridge is then opened reductively either directly or after oxidation of the 6:19-ethers to lactones or preferably after introduction of a 4,6-3-oxo grouping. Acylolytic cleavage of the 4-3-oxo-6:19-ethers followed by alkaline hydrolysis gives 4,6-3-oxo-19-hydroxy-steroids. The 19-hydroxycompounds formed are easily converted into 19-norsteroids by known methods.

Über Steroide, 189. (vorläufige) Mitteilung; 188. Mitt. vgl.J. Kalvoda, J. Schmidlin, G. Anner undA. Wettstein, Exper.18, 398 (1962).  相似文献   

8.
A major cytokinin found in coconut milk was isolted by using the tobacco callus growth-promoting assay as a guide during purification. The structure of the factor was determined to be 14-O-{3-O-[-d-galactopyranosyl-(12)--d--galactopyranosyl-(13)--L-arabinofuranosyl]-4-O-(-L-arabinofuranosyl)--d-galactopyranosyl}-trans-zeatin riboside [G3A2-ZR] by various NMR techniques, including heteronuclear multiple bond connectivity by 2D multiple quantum NMR (HMBC), as well as mass spectroscopy and sugar analysis. The optimum concentration of G3A2-ZR for cytokinin activity in the tobacco callus assay was estimated to be 5×10–6 M, so that G3A2-ZR is one order of magnitude more potent than 1,3-diphenylurea and one order less potent than zeatin riboside. At least 20% of the cytokinin activity of coconut milk could be attributed to G3A2-ZR.  相似文献   

9.
Summary In isolated guinea-pig atria, the-adrenolytic isomerd(–)INPEA provoked a stronger prolongation of the refractory period (rp) than did the inactivel(+) isomer. The-adrenolytic drug MJ 1999 prolonged likewise the rp, although it caused no unspecific effect, i.e. an inhibition of contractile force. These observations lead to the conclusion that not only the unspecific local anaesthetic but also the specific-adrenolytic effect is of importance for the prolongation of rp.  相似文献   

10.
Zusammenfassung Die als Alexandrin beschriebene Substanz, die als Bestandteil vonCentaurea alexandrina isoliert worden ist, wurde als -sitosterol--d-glukosid identifiziert.  相似文献   

11.
Zusammenfassung Eine Halogen enthaltende Indolverbindung wurde zum Nachweis der-d-Glucuronidase benutzt. Die Methode eignet sich zur Lokalisierung von reaktiven Kleinzellen im reticuloendothelialen System.  相似文献   

12.
Riassunto Dalla Stella alpina (Leontopodium alpinum Cass, Gnaphalieae-Asteraceae) vengono isolati la luteolina (3, 4, 5, 7 tetraidrossiflavone) ed i suoi 4-e 7-O--d glucosidi.  相似文献   

13.
Summary 3, 16-diacetoxy-5-pregnane-20-one and the analogue pregn-5-ene derivative have been converted into (22R, 25R)-22, 26-imino-5-cholestane-3, 16-diol. The configuration at C-22 and C-25 was determined by transformation into the known (22R, 25R)-5-solanidane-3-one. Application of the Ruschig method led to (25R)-22,26-imino-5-cholest-22(N)-ene-3, 16-diol.

Solanum-Alkaloide. XVI. Mitteilung. — XV. Mitteilung:K. Schreiber undH. Ripperger, Tetrahedron Letters Nr.27, 9 (1960).  相似文献   

14.
- . 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   

15.
Summary Starting from methyl 3-oxo-4-etienate, the authors prepared 17-hydroxymethyl-4-androsten-3-one and 11-hydroxy-17-hydroxymethyl-4-androsten-3-one. Chlorination of 17-acetoxymethyl-4-androsten-3-one yielded 4-chloro-17-acetoxymethyl-4-androsten-3-one. 17-Hydroxymethyl-1, 4-androstadien-3-one was obtained from 17-hydroxymethyl-4-androsten-3-one, both by chemical and biological methods.  相似文献   

16.
A new radioimmunoassay has been developed for thymosin 4 by generating rabbit polyclonal antibodies against the synthetic N-terminal peptide fragment 1–15 coupled to KLH. The synthetic analogue [Tyr12]-thymosin 4 (1–15) was used as tracer. This radioimmunoassay, with a useful range of 10–1000 pmoles, showed cross-reactivity with the second homologous -thymosin of man and rat (thymosin 10) but not of calf (thymosin 9). This radioimmunoassay, together with an improved radioimmunoassay for the N-terminus of parathymosin , was employed for the measurement of the levels of thymosin 4 and parathymosin in nuclear and extranuclear extracts of calf thymus. The bulk of these polypeptides was found in the extranuclear material whereas only traces were observed in the nuclear environment, which indicates the extranuclear localisation of - and -thymosins.  相似文献   

17.
Zusammenfassung Ecdyson, ein Häutungshormon der Insekten, wurde ausgehend von Ergosterin in 14 Stufen synthetisiert. Wesentliche Zwischenprodukte waren (20S)-2, 3-Diacetoxy-20-formyl-5-pregn-7-en-6-on und (22R)-2, 3-Diacetoxy-14, 22-dihydroxy-25-(tetrahydropyran-2-yloxy)-5-cholest-7-en-6-on.  相似文献   

18.
Zusammenfassung Papierelektrophoretische Lipiduntersuchungen von- und-Plasmacytom — Paraproteinseren nach Kolloidaldextranbelastung erfassen eine neue, in der Diagnostik des Plasmocytoms verwertbare Eigenschaft: die Paraproteinlipidkomponente (PL) vermag, entgegen den-Lipoproteinen, mit Dextran keine Assoziationsfraktion zu bilden.

My thanks are due toJosipa Franjkovi for her technical assistance.  相似文献   

19.
Zusammenfassung Die Aktivität der Aminopeptidasen in Ohrspeicheldrüsen wurde gemessen. Glycyl-Prolin-naphthylamid, Alanin-naphthylamid, Leucin-naphthylamid, Methionin-naphthylamid, und Arginin-naphthylamid wurden von der Mikrosomenfraktion und der löslichen Fraktion schnell gespalten. Das Glycyl-Prolin-naphthylamid spaltende Enzym war in Ohrspeicheldrüsen in relativ grösserer Menge vorhanden. Die Aufspaltung von Glycyl-Prolin-naphthylamid in Glycyl-Prolin und-Naphthylamin wurde papierchromatographisch nachgewiesen.  相似文献   

20.
Zusammenfassung Die optischen Drehungen einiger 20, 25d; 20, 25l; 20, 25d; und 20, 25-l-Sapogenine wurden bestimmt. Die ersten drei Serien gaben übereinstimmend linksdrehende Werte, aber die letztere Gruppe erwies sich als rechtsdrehend.Die Struktur der vier Serien der Sapogenine folgte aus der Analyse dieser Befunde. Der mögliche Mechanismus bei der Entstehung dieser Verbindungen aus Pseudosapogeninen wurde besprochen. Die Autoren gelangen zum Schluss, dass sterische Faktoren an C20 und C25 die Richtung der Ringschliessung beeinflussen.
Steroidal sapogenins. XXX stereochemistry of the side chain
  相似文献   

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