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1.
Zusammenfassung Nebennierenschnitte von Ratten, Meerschweinchen und Menschen synthetisierten 17-Hydroxyprogesteron, 11-Deoxycortisol und Cortisol aus 17-Hydroxypregnenolon. Diese Verbindung, als Ausgangsprodukt für die Cortisolsynthese, ist ebenso wirksam wie pregnenolon. Die Umwandlung von 17-Hydroxypregnenolon in Dehydroepiandrosteron verläuft weniger vollkommen als zu 17-Hydroxycorticoiden.  相似文献   

2.
Summary The conversion of cholesterol into 19-nor-5-cholestan-3-ol by the spongeAxinella polypoides involves a partial loss (40%) of the 3-hydrogen atom; moreover administration to the sponge of [4-14C]cholesterol tritiated at C-4 and C-7 showed that the 4- and 7-hydrogen atoms are retained in this conversion. A competitive uptake experiment, [4-14C]cholesterol vs. [7-3H2]5-cholestanol, showed that the sponge utilized exclusively cholesterol for the production of 19-nor-5-cholestan-3-ol.Part of this work has been presented at the Nato Conference on Marine Natural Products (Jersey, Great Britain, October, 1976).-This contribution is part of the Programma finalizzato Oceanografia e Fondi marini-sottoprogetto Risorse biologiche C.N.R. Italy.  相似文献   

3.
Summary In a group of 84 pairs of 11-year-old children of both sexes, the level of the 1-antitrypsin ( 1-AT) were ascertained in the autumn and spring. Although the mean levels of 1-AT in the two seasons hardly differed, the highly significant seasonal changes in the distribution curves of 1-AT values were noted in boys, whereas the levels showed higher stability in girls.  相似文献   

4.
Summary Claviceps purpurea 275 F.I. fed with -aminobutyric acid produces ergostine with the corresponding -hydroxy--aminoacid undiluted by endogenous aminoacid. Almost all the -aminobutyric acid not incorporated into the ergostine remains unchanged in the medium. The significance of these results in the biosynthesis of ergot alkaloids is discussed.  相似文献   

5.
Summary On treatment of 3-hydroxy-5-steroids with lead tetra-acetate formation of 3, 9-oxides is observed. The yields of this ring closure reaction decrease significantly in the order 11-keto, 9, 11-ene and ring-C saturated compounds.  相似文献   

6.
    
Zusammenfassung Lokale Kühlung des Rückenmarks bei Katzen in Barbituratnarkose führte zu einer Steigerung der Aktivität sowohl der - als auch der-Motoneurone, die durch Wiedererwärmung wieder rückgängig gemacht werden konnte. Die Schwelle für diese Aktivitätssteigerung lag bei den-Motoneuronen niedriger als bei den -Motoneuronen. Erwärmung über die Ausgangstemperaturen unterdrückte eine bei normaler Temperatur vorhandene Spontanaktivität der-Motoneurone.  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.
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   

9.
Zusammenfassung Mit Hilfe von Immunoelektrophorese und Doppeldiffusiontechnik wurden in Humanmilch an Blutplasmaproteinen serologisch identifiziert: Praealbumin, Albumin, Acid Seromucoid, 1-Glykoprotein (3·5 S), Coeruloplasmin, Haptoglobin, 2- oder-Lipoprotein, Transferrin, Fibrinogen, 2A-Globulin, 2M-Globulin und-Globulin.  相似文献   

10.
Zusammenfassung Es wurde gefunden, dass die strukturverwandte Verbindung,-Dimethylphenethylaminopropan-2-on (AY-18 627) für das Blockieren der Norepinephrinaufnahme im Rattenherzen wirksamer ist als AY-14 948. Unter gegebenen Versuchsbedingungen riefen diese Verbindungen weder eine Änderung im endogenen Bereich der Hirn- und Herzkatecholamine noch im Serotoningehalt des Rattenhirns hervor.  相似文献   

11.
Summary Tritium distribution on randomly labelled taurocholate (TC) was estimated at 28%, 4%, 1% and <0.5% on the hydrogens opposite the 3-, 7- and 12-OH groups and taurine moiety respectively. Anomalously,C. perfringens 3-hydroxysteroid dehydrogenase (3-HSDH) catalyzed tritium loss of 36% on formation of 7-, 12-dihydroxy-3-keto-5-cholanoate, implying additional losses of tritium at other sites by this enzyme.This work is supported by the National Cancer Institute.  相似文献   

12.
Zusammenfassung Während unserer Untersuchungen über die mikrobiologische Dehydrierung verschiedener 16-Methylsteroide durch Bakterienkulturen vonCorynebacterium simplex, wurde eine neue Art von Umwandlung beobachtet. Von 16-Methyl-9(11)-pregnen-17, 21-diol-3, 20-dion-21-acetat ausgehend, gelang es aus den Kulturfiltraten 16-Methyl-1, 4-pregnadien-9, 11-epoxy-17, 21-diol-3, 20-dion zu isolieren. In einigen Fällen wurde auch das4-Derivat dieser Verbindung als Nebenprodukt erhalten.  相似文献   

13.
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   

14.
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   

15.
-Tocopheryl-succinate (TS) is a synthetic, anti-neoplastic derivative of -tocopherol. Here we studied the effects of free and high-density lipoprotein subclass 3 (HDL3)-associated TS on the growth of human (A549) and mouse Lewis (LL2) lung carcinoma cells. Both free and HDL3-associated TS inhibited A549 growth in a time- and concentration-dependent manner. Treatment of A549 cells with TS-enriched HDL3 led to DNA fragmentation and a time-dependent decrease in immunoreactivity of poly(ADP-ribose)polymerase. Uptake experiments revealed a high capacity for selective TS uptake in excess of holoparticle endocytosis. Overexpression of scavenger receptor class B, type I (SR-BI), the prime receptor mediating selective lipid uptake, in A549 cells resulted in significantly increased selective TS uptake, a finding associated with complete cellular growth arrest. The present in vitro findings were verified in an in vivo model: tumor inoculation in C57BL6 was performed with either wild-type, -galactosidase- or SR-BI-overexpressing LL2 cells. After tumor inoculation, the animals received six consecutive intravenous injections of TS. This experimental setup resulted in significantly reduced tumor burden in animals that were inoculated with SR-BI-overexpressing LL2 cells but not in animals inoculated with wild-type or -galactocidase-transfected cells. Based on our in vitro and in vivo findings, we propose that SR-BI could provide a novel route for HDL3-mediated drug delivery of anti-neoplastic drugs.Received 8 March 2004; received after revision 7 April 2004; accepted 26 April 2004  相似文献   

16.
Summary The sterol fraction from leaves of the potato plant,Solanum tuberosum, was found to contain a minor constituent, the structure of which has been established as 4-methyl-5-stigmasta-7,24(28)-diene-3-ol (I). This sterol is most probably identical with 1-sitosterol and has the same constitution as citrostadienol, differing only in the configuration of the 24 (28)-double bond.

Sterine und Triterpenoide. III. Mitteilung. — II. Mitteilung s. 3.  相似文献   

17.
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   

18.
Summary The amino acid sequence was compared among the three allelic variants (allozymes) ofsn-glycerol-3-phosphate dehydrogenase inD. virilis, which are detected by one-dimensional electrophoresis. The GPDHf variant was different from the GPDHm by only one substitution of 68-lysine for asparagine; GPDHs differed from GPDHm by substitution of 127-glycine for arginine. No electrophoretically silent substitutions were found in a total of 352 amino acid residues.  相似文献   

19.
Previous studies conducted in cytosolic extracts of the freshwater hydrozoanHydra vulgaris led to the finding of an abundant 11(R)-lipoxygenase catalyzing the peroxidation of polyunsaturated fatty acid (PUFAs) on the tenth carbon atom from the aliphatic end (10 peroxidation). Here we describe experiments aimed at identifying the actual metabolites generated in vivo by such enzymic activity. Homogenates ofH. vulgaris polyps were analyzed by HPLC. This showed the presence of three major components chromatographically identical to three metabolites obtained when incubating the homogenates with exogenous -linolenic acid (-LA). The presence, in extracts of polyps prelabelled with [14C]--linolenic acid, of radioactive metabolites displaying the same chromatographic properties, substantiated the hypothesis that the natural products isolated in vivo are derived from -LA. Gas chromatographic analyses revealed that this was the most abundant PUFA in both free and phosphoglyceride-bound fatty acid pools. [1H]-NMR analysis of the endogenous substances, carried out in comparison with products obtained from exogenously incubated -LA, indicated that their structures were those of 9-hydroxy-, 9-hydroperoxy- and 9-keto-octadeca-10E-12Z-15Z-trienoic acids (9--HOTrE,-HPOTrE and-KOTrE).Hydra homogenates transformed 9--HPOTrE partly into 9--HOTrE and partly into 9--KOTrE. Chiral phase HPLC conducted on 9--HOTrE established that this metabolite was composed mostly of theR anantiomer. These observations, and the finding that the presence of exogenous arachidonic acid in incubated homogenates significantly reduces the production of -LA metabolites, provide strong evidence that these compounds are produced by an enzymic activity identical to the previously-describedH. vulgaris (R)-10-lipoxygenase. Further experiments suggested that -LA, acting as the native substrate for this enzyme, is mainly esterified on the 2 position ofHydra phosphoglycerides, and that the production of the -LA metabolites described here for the first time from natural sources, can be potentially enhanced in vivo by stimuli activating phospholipase A2.  相似文献   

20.
Zusammenfassung 4-C14-Testosteron wurde durch Mäuseplazenta in vitro zu Steroiden umgesetzt: 3-Hydroxy-5-androstan-3, 17-dion, 3-Hydroxy-5-androstan-3, 17-dion, 4-Androsten-3, 17-dion und 5-Androstan-3, 17-dion. Eine Umsetzung von Testosteron zu Östrogenen wurde nicht nachgewiesen.  相似文献   

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