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1.
Zusammenfassung Die Struktur desp-Brombenzoates des Benzilsäureumlagerungsproduktes von 3, 17-Diacetoxy-11-hydroxy-12-oxo-5-9(11)-androsten wurde durch dreidimensionale Röntgenstrukturanalyse eines Einkristalls als 3-p-Brombenzoat des 11-Carboxy-3, 11, 17-trihydroxy-13-C-nor-5-androstan 11a, 17-Laktons erkannt.  相似文献   

2.
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   

3.
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   

4.
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   

5.
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   

6.
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   

7.
Summary The synthesis of 17-hydroxy-17-hydroxymethyl-4-androsten-3-one fromReichsteins compound S is described. Transformation of 3,3-ethylenedioxy-17-hydroxy-17-hydroxymethyl-5-androsten into 17-methyl-isotestosterone demonstrates the configuration of the substituents at C-17.  相似文献   

8.
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   

9.
Defensive steroids from a carrion beetle (Silpha americana)   总被引:2,自引:0,他引:2  
Summary The defensive anal effluent discharged bySilpha americana in response to disturbance contains a mixture of steroids stemming from a glandular annex of the rectum. The compounds have been characterized as 15-hydroxyprogesterone (1, principal component), 5-pregnan-15-ol-3, 20-dione (2), 5-pregnan-3, 15-diol-20-one (3), 5-pregnan-7, 15-diol-3,20-dione (4), 5-pregnan-3, 7, 15-triol-20-one (5), 5-pregnan-16-ol-3,20-dione (6), and 5-pregnan-3, 16-diol-20-one (7), none previously found in insects. Bioassays with jumping spiders showed compounds1 and6 to be feeding deterrents at the 1 g level.Paper No. 78 of the series: Defense Mechanisms of Arthropods. Study supported by NIH (Grants AI-02908, AI-12020). We thank Maura Malarcher and Maria Eisner for excellent technical help, and the Squibb Institute of Medical Research for samples of authentic reference compounds.  相似文献   

10.
Zusammenfassung Die Bildung von 11-Carboxy-3, 11, 17-trihydroxy-13-C-nor-5-androstan 11a,17-Lakton aus 3, 17-Diacetoxy-11-hydroxy-12-oxo-5-9(11)-androsten wird beschrieben. Der Mechanismus und die Stereochemie dieser Umwandlung (Retro-Aldolkondensation und Benzilsäureumlagerung) wird diskutiert.  相似文献   

11.
Riassunto La valutazione istochimica delle attività 3-idrossisteroide deidrogenasica (3-HSD), glucoso-6-fosfato deidrogenasica (G-6-PD) e 20-idrossisteroide deidrogenasica (20-HSD) a livello dell'ovaio di ratte trattate per 20 giorni con progesterone, testosterone, estradiolo o con l'associazione progesterone-estradiolo, permette di rilevare che, a dosi inibenti l'ovulazione, solo negli animali trattati con estradiolo o con progesterone ed estradiolo si inibisce la comparsa dell'attività 20-HSD nei corpi lutei (C.L.) e si riduce quella 3-HSD e G-6-PD nei follicoli e nella interstiziale.  相似文献   

12.
Zusammenfassung Es wurde der Abbau von Aminosäuren durch Wasserstoffsuperoxyd in Gegenwart von Eisensalzen untersucht. Papierchromatographische Analyse zeigte, dass dabei aus-Aminobuttersäure-Alanin und Glycin, aus-Alanin und Serin Glycin entsteht. Die Bildung von-Alanin und Asparaginsäure aus-Aminobuttersäure und von Asparaginsäure aus Glutaminsäure konnte ebenfalls festgestellt werden. Diese Resultate werden in Zusammenhang gebracht mit dem Mechanismus der Photolyse von Aminosäuren in Gegenwart von TiO2.  相似文献   

13.
Riassunto È stata studiata con metodi istochimici la distribuzione della 5-3-idrossisteroide deidrogenasi ( 5-3-HSDH) e delle 17-idrossisteroide deidrogenasi (17-HSDH), DPN- e TPN-dipendenti, nell'ovario di gallina ovulante. Mentre la 5-3-HSDH è presente in tutti i tessuti a secrezione steroide dell'ovario, la 17-HSDH è localizzata solo nelle cellule della granulosa.  相似文献   

14.
Summary Photolysis of N-nitroso-22,26-imino-5-cholestane-3,16-diols in acidic solution leads to the corresponding spirosolane alkaloids soladulcidine, solasodine and tomatidine, respectively.

Photochemische Reaktionen, 5. Mitteilung. — 3. und 4. Mitteilung vgl.2. Die vorliegende Arbeit ist zugleich 62. Mitteilung der ReiheSolanum-Alkaloide.  相似文献   

15.
Summary 6-Methoxy-9,10 -pregna-4,6-diene-3,20-dione inhibites the 4-3-oxosteroid-5-reduction in microsomes and the 4-3-oxosteroid-5-reduction in the soluble fraction of male rat liver. The 3- and 3-hydroxysteroid dehydrogenase are not inhibited by this substance.

Diese Arbeit wurde von der Firma Hoffmann-La Roche, Basel, unterstützt.  相似文献   

16.
Summary Two new syntheses of Chloramphenicol are described starting from the diastereoisomers of -phenylserinmethyl ether and cinnamyl alcohol methyl ether respectively. The configurational correlation of the diastereoisomers of -phenylserin-methyl ether with -phenylserin and chloramphenicol is discussed. A new method for transforming erythro--phenylserinol into threo--phenylserinol is described. New examples of the Neighboring group effect were studied. The sterical course of the addition of methylhypobromite to the double bond is discussed.  相似文献   

17.
Summary The structure of Cinobufagin is shown to be 3-Hydroxy-14, 15-epoxy-16-acetoxy-5-bufa-20, 22-dienolide.

Die ausführliche Publikation erscheint demnächst in den Helv. chim. Acta.  相似文献   

18.
Summary 5-pregnane 11, 17, 21-triol 3, 20-dione (dihydrocortisol) has been isolated and identified in the urine of patients with feminizing adrenal cortical cancer. This steroid showed the same Rf as synthetic dihydrocortisol in six different chromatographic systems. After acetylation, its Rf was the same as that of 21 monoacetate of dihydrocortisol. After bismuthic or chromic oxydation, it had the same chromatographic Rf as 5-androstane 11-ol 3, 17-dione and 5-androstane 3, 11, 17-trione respectively. After chromic oxydation of its acetate, the Rf was the same as that of 21 monoacetate of cortisone.  相似文献   

19.
G-protein signaling: back to the future   总被引:14,自引:0,他引:14  
Heterotrimeric G-proteins are intracellular partners of G-protein-coupled receptors (GPCRs). GPCRs act on inactive G·GDP/G heterotrimers to promote GDP release and GTP binding, resulting in liberation of G from G. G·GTP and G target effectors including adenylyl cyclases, phospholipases and ion channels. Signaling is terminated by intrinsic GTPase activity of G and heterotrimer reformation – a cycle accelerated by regulators of G-protein signaling (RGS proteins). Recent studies have identified several unconventional G-protein signaling pathways that diverge from this standard model. Whereas phospholipase C (PLC) is activated by Gq and G, novel PLC isoforms are regulated by both heterotrimeric and Ras-superfamily G-proteins. An Arabidopsis protein has been discovered containing both GPCR and RGS domains within the same protein. Most surprisingly, a receptor-independent G nucleotide cycle that regulates cell division has been delineated in both Caenorhabditis elegans and Drosophila melanogaster. Here, we revisit classical heterotrimeric G-protein signaling and explore these new, non-canonical G-protein signaling pathways.Received 21 October 2004; received after revision 20 November 2004; accepted 30 November 2004  相似文献   

20.
Summary The-d-fucosidase and -l-fucosidase activities of digestive juice ofHelix pomatia have been studied.-d-fucosidase can be separated from-d-galactosidase by heat inactivation.  相似文献   

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