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1.
Zusammenfassung Zwei neue, furanoide Metaboliten wurden aus einer Kultur vonRhizoctonia solani isoliert und als 2-Furyl-hydroxymethyl-Keton und 1,2-bis-(2-Furoyl)-1,2-Dihydroxyaethan identifiziert und durch Totalsynthese bestätigt.  相似文献   

2.
Summary The chloroform extract of anthers ofSolandra nitida contains 3-acethyl-6-methyl-1,2-pyran-2,4(3H)dione (dehydroacetic acid) as one of the main products.  相似文献   

3.
Summary The anthelmintic properties of several imidazo[1,2-a]pyridine carbamates and benzimidazole carbamates againstHymenolepis nana are compared. The results of this study, coupled with previous work, indicate that methyl 6-(trichloroethenyl)-imidazo[1,2-a]pyridine-2-carbamate has the potential of being a broad spectrum anthelmintic, effective against both nematodes and cestodes.Acknowledgments. We are indebted to Miss Marianne Hardy for excellent technical assistance. Our sincere thanks are extended to the Merck, Sharp & Dohme and Hoechst companies for the compounds tested in the present study.  相似文献   

4.
Zusammenfassung Ausgew?hltecis- undtrans-Isomere, Derivate des 1,2,3,4-Tetrahydro-1,2-diphenylnaphthalins, wurden beschrieben. Der basische ?ther VII blokkierte die Nidation in der Ratte bei einer t?glichen Dosis von 20γ/kg per os.   相似文献   

5.
Zusammenfassung Aus den Biberdrüsen wurdecis-Cyclohexan-1,2-diol isoliert und charakterisiert.

The support of this work by the Colombo Plan administration of Canada is gratefully acknowledged.  相似文献   

6.
Riassunto L'acido 1,2 benzisotiazol-3-ilacetico (BIA) ha mostrato una forte azione sulla proliferazione cellulare di espianti di tuberi dormienti diHelianthus tuberosus, sostanzialmente simile a quella indotta dall'acido indol-3-acetico.  相似文献   

7.
Zusammenfassung 2-Methyl-1,2-bis-(3-pyridyl)-1-propanon (Su 4885) hemmt beim Hund die Ausscheidung von 17-OH-Steroiden aus den Nebennieren und hemmtin vitro ähnlich wie Amphenon den ACTH-Effekt auf Ratten-, Meerschweinchen-und Hunde-Nebennieren.In situ bei der Ratte hat es jedoch keine Amphenon-Wirkung, von dem es sich auch sonst unterscheidet.  相似文献   

8.
Insulin action is initiated by binding to its cognate receptor, which then triggers multiple cellular responses by activating different signaling pathways. There is evidence that insulin receptor signaling may involve G protein activation in different target cells. We have studied the activation of G proteins in rat hepatoma (HTC) cells. We found that insulin stimulated binding of guanosine 5′-O-(3-thiotriphosphate) (GTP-γ-35S) to plasma membrane proteins of HTC cells, in a dose-dependent manner. This effect was completely blocked by pertussis toxin treatment of the membranes, suggesting the involvement of G proteins of the Gα i/Gα o family. The expression of these Gα proteins was checked by Western blotting. Next, we used blocking antibodies to sort out the specific Gα protein activated by insulin stimulation. Anti-Gα il,2 antibodies completely prevented insulin-stimulated GTP binding, whereas anti-Gα o,i3 did not modify this effect of insulin on GTP binding. Moreover, we found physical association of the insulin receptor with Gα i1,2 by copurification studies. These results further support the involvement of a pertussis toxin-sensitive G protein in insulin receptor signaling and provides some evidence of specific association and activation of Gα i1,2 protein by insulin. These findings suggest that Gα i1,2 proteins might be involved in insulin action. Received 23 September 1998; received after revision 23 November 1998; accepted 25 November 1998  相似文献   

9.
Zusammenfassung Die Reaktion gewisser heterocyclischer Ketone mit Äthanol in Gegenwart von Säure ist abhängig von der Ringgrösse und wird plötzlich durch die Wechselwirkung von 1,2-cis- oder 1,3-diaxalen Substituenten beeinflusst.  相似文献   

10.
An improved test for Africanized honeybee mitochondrial DNA   总被引:2,自引:0,他引:2  
Mitochondrial DNA derived fromApis mellifera scutellata, the ancestor of the Africanized bees of the New World, lacks aBglII restriction site found in other types of honeybee1,2. We present primers allowing amplification of a 485-bp section of the cytochrome b gene containing this site, using the polymerase chain reaction. Digestion of the amplifiel product withBglII yields contrasting patterns between Africanized and other honeybees.  相似文献   

11.
Five novel 1,2-sn-diacylglycerols with diterpenoid acyl moieties in thesn-1 position were isolated and characterized, together with the corresponding 1,3-sn-diacylglycerols, from three species of dorid nudibranchs molluscs. Their potent activity as morphogens in vivo in theHydra tentacle regeneration assay and their parallel activity as activators of rat brain protein kinase C (PKC) in vitro are reported here. Our findings promote the use of these compounds as useful molecular probes for both in vivo and in vitro studies on the participation of PKC in cell development.  相似文献   

12.
Lectin binding, endo-chitinase binding and enzymatic degradation studies show that the epidermal cuticle of the bony fishParalipophrys trigloides (Blenniidae) is chitinous. This is the first evidence that a vertebrate species possesses a chitinous tissue. Recently aXenopus gene has been identified which has significant sequence similarity to the catalytic domain of yeast chitin synthase III, a chitin producing enzyme1,2. Taken together these two findings imply that chitin synthesis capability may be a basic vertebrate feature.  相似文献   

13.
Zusammenfassung Die hauptsächlichsten pharmakologischen Eigenschaften von 3-(p-Propionyl-o-methoxy-phenoxy)-1,2-propandiol (DA 1128) werden beschrieben. Wie Mephenesin zeigt DA 1128 eine beträchtliche depressorische Wirkung auf das Z.N.S. Das neue Arzneimittel jedoch zeigt — in Abweichung von Mephenesin — nur eine schwache paralytische Wirkung und eine geringe muskelrelaxierende Wirkung, ist weniger toxisch und besitzt keine hämolytische Wirkung. DA 1128 wird bei Versuchstieren rasch resorbiert.  相似文献   

14.
Zusammenfassung Die polarographische Reduktion polyzyklischer are matischer Verbindungen kann als 1,2-, 1,4- oder 1,6 Addition erfolgen. Der Verlauf der Reaktionen lässt sic aus der Abnahme der Resonanzenergie ableiten.

F. T. Wallenberger, Tetrahedron Letters9, 5–9 (1959).  相似文献   

15.
The non-steroidal ecdysone agonist RH-5849 (1,2-dibenzoyl-l-tert-butylhydrazine) was found to be an effective neurotoxicant on injection into the American bird grasshopper,Schistocerca americana (Drury). Treated grasshoppers became immediately hyperactive, followed by loss of coordination, paralysis and eventually death. We also discovered that this compound induced bilateral autotomy of the metathoracic legs during the early stages of intoxication. However, no evidence of ecdysonergic or morphogenetic activities was observed. Synergism studies with neurotoxins of known mode of action suggested that RH-5849 has a mechanism of action similar to that of 4-amino pyridine, which blocks potassium channels.  相似文献   

16.
Zusammenfassung Auf Grund stereochemischer Überlegungen wird angenommen, dass eine ionische 1,2-cis-Abspaltung in der Cyclopentan-Reihe leichter erfolgt als im Cyclohexan-System. In Übereinstimmung damit wird eine gute Methode für die Herstellung von 1-Cyclopentennitril beschrieben.  相似文献   

17.
4-Hydroxyurazole     
Zusammenfassung Durch Hydroxylaminolyse von 1,2-bis (äthoxycarbonyl)hydrazin wurde Natriumsalz von 1-Äthoxycarbonyl-2-hydroxylaminocarbonylhydrazin hergestellt und mit wässeriger Salzsäure auf pH<1 in 4-Hydroxyurazol (N-Hydroxybicarbamimid) synthetisiert.

This investigation was supported by Contract No. PH43-65-94 with Chemotherapy, National Cancer Institute, National Institutes of Health, U.S. Public Health Service.  相似文献   

18.
Zusammenfassung Mit Hilfe der PM-Methode ist die molekulare Rotation von (–)-1,2/3,4-Cyclohexantetrol untersucht worden. Daraus geht hervor, dass diese Verbindung in wässeriger Lösung als Gemisch der C 1- und 1 C-Konstellationen vorliegt.

Part III. Part II, seeS. Yamana, Bull. chem. Soc. Japan34, 1212 (1961).  相似文献   

19.
Summary The soil fumigant 1,2-dibromo-3-chloropropane (I) undergoes hydrolysis in the rat to a series of epoxide metabolites. Alkylation of glutathione by these epoxides produces 2 urinary metabolites identified as the mercapturic acids VI (R=COCH3) and VII (R=COCH3). Hydrolysis of the epoxides produces the male antifertility agentsa-chlorohydrin (IX, X=Cl) anda-bromohydrin (IX, X=Br) which are oxidatively metabolized to oxalic acid (XII), thus causing renal damage. These metabolic pathways can explain the toxic nature of the fumigant as a carcinogen, a male chemosterilant and as an agent causing kidney damage.This work was supported in part by the National Health and Medical Research Council of Australia.  相似文献   

20.
Summary The addition of citraconic anhydride to 1-vinyl-6-methoxy-3,4-dihydro-naphthalene according toDiels-Alder's method yielded two isomeric hydro-phenanthrene-dicarboxylic acids. One of these two acids has been converted into 2-methyl-7-methoxy-1,2,3,4,9,10-hexahydro-1,2-dicarboxylic-acid.

Mitteilung « Über Steroide » (65. Mitt. siehe Helv. chim. Acta30, 1037 [1947]), sowie XX. Arbeit « Über östrogene Carbonsäuren » (XIX. siehe Exper.3, 279 [1947]).  相似文献   

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