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1.
The components of individual Dufours glands excised fromAnoplolepis custodiens workers were analysed by GC-MS. In addition to then-alkanes andn-alkenes previously reported2 in these glands, primary alcohols (C19-C22), secondary alcohols (C20-C23), 2-ketones (C20-C23) and possibly carboxylate ethyl esters (C19 and C21) were identified as components of these glands. It seems possible that these high-boiling compounds are used by the workers in laying trails on the hot sandy surfaces of their characteristic habitat and in lining of the inner walls of nests, but no standard compounds have been available to us for any behavioral studies.  相似文献   

2.
Summary Pheromonal secretions produced by females and males of the noctuid moth,Mocis megas (Guénée) have been analyzed by gas chromatography and mass spectrometry (EI (electron impact) and CI (chemical ionization)). The female sex pheromone was a blend of (Z,Z,Z) 3,6,9 heneicosatriene (55%) and (Z,Z) 3,6-cis-9S, 10R-epoxyheneicosadiene (45%). Male secretion produced at the level of a prothoracic organ was a blend of two unsaturated major hydrocarbons: (Z,Z) 6,9 heneicosadiene, (64%) and (Z,Z,Z) 3,6,9 heneicosatriene (24%) and C19, C20 and C22 homologues (total ratio 12%), as minor components. The trienic hydrocarbon was present in both sexes. The behavioral role of this male secretion has not yet been elucidated.  相似文献   

3.
Summary The synthesis of some unsaturated polychloro compounds, starting from the heptachloropropanes, octachloropropane and hexachloropropane, by means of aluminium in ether is described. For four compounds C6Cl8, subject to some conversions, the structure of octachlorohexatriene-(1, 3, 5) has been made probable, and the possibility of a special stereoisomerism is discussed.

Mitteilung «über Polyhalogenverbindungen»; 1. Mitteilung siehe Chem. Ber.80, 206 (1947). Die ausführliche Veröffentlichung dieser Arbeit folgt ebendort.  相似文献   

4.
Summary 4 cocarcinogenic compounds have been isolated from croton oil by combination of countercurrent distribution and column chromatography without chemical procedures. The hitherto unknown component A3 is described as an acetic acid and palmitic acid Phorboldiester with the formula C38H60O8.

Der Deutschen Forschungsgemeinschaft danke ich für Personal- und Sachbeihilfen, Fräulein G.Bingmann für ihre Mitarbeit.  相似文献   

5.
Summary The chemical structure of the polyenoic fatty acids occuring in organ phosphatides and in fish oils is reviewed. The double bonds of all these polyenoic acids are arranged in divinylmethane pattern. Except some of the C16-polyenoic acids of fish oils, these polyenoic acids belong either to the oleic, linoleic or linolenic acid type and have chain lengths C18, C20, and C22. Polyenoic acids of the oleic acid type are present only in small amounts in phosphatides of mammalian origin. Fish oils are lacking in these but predominantly contain polyenoic acids of the linolenic acid type.Metabolic studies have shown that polyenoic acids of linoleic acid type (e.g. arachidonic acid) originate from linoleic acid and those of the linolenic acid type (e.g. C20-pentaenoic and C22-hexaenoic acid) from linolenic acid-both supplemented exogenous-by extension of the carbon chain by acetate on the side of the carboxylic acid group and introduction of additional double bonds in the divinylmethane pattern directed toward the carboxylic acid group. There is some evidence, however, that a total synthesis of the polyenoic acids of the oleic acid type occurs in the animal body.The transformation of linolenic to C22-hexaenoic acid and some intermediate reactans have been investigated more precisely by means of the tracer method. As far as the biosynthesis of the polyenoic fatty acids is concerned there are no fundamental differences in different vertebrates.

Nach einem Vortrag auf der gemeinsamen Tagung der deutschen, französischen und schweizerischen Biochemiker in Zürich vom 10.–12. Oktober 1960.  相似文献   

6.
Alcohol dehydrogenase 3 (ADH3) has been assigned a role in nitric oxide homeostasis due to its function as an S-nitrosoglutathione reductase. As altered S-nitrosoglutathione levels are often associated with disease, compounds that modulate ADH3 activity might be of therapeutic interest. We performed a virtual screening with molecular dockings of more than 40,000 compounds into the active site of human ADH3. A novel knowledge-based scoring method was used to rank compounds, and several compounds that were not known to interact with ADH3 were tested in vitro. Two of these showed substrate activity (9-decen-1-ol and dodecyltetraglycol), where calculated binding scoring energies correlated well with the logarithm of the k cat/K m values for the substrates. Two compounds showed inhibition capacity (deoxycholic acid and doxorubicin), and with these data three different lines for specific inhibitors for ADH3 are suggested: fatty acids, glutathione analogs, and cholic acids.  相似文献   

7.
Summary Investigations of the chemical changes in fats subjected to cathode rays (100 Mrad) indicated the formation of shorter fatty acid chains. Besides splitting off the terminal methyl groups, especially the medial C-C-bonds are readily split and saturated and unsaturated C6-C11-fragments are formed. The double bond is relatively resistant, but the C-C-bond near the double bond is easily fractured.  相似文献   

8.
Summary 1-O-Monoalkylglycerols with C12 to C20 chains were identified in the scent, gland secretions of the western diamondback rattlesnake (Crotalus atrox). This is the first documentation of these compounds in the skin secretions of a reptile.  相似文献   

9.
Summary The intoxication of 15-day-old green pea seedlings with 1% gaseous SO2 causes an important concentration fall of some free ketoacids (pyruvic, oxalacetic, -ketoglutaric) and of glyceraldehyde in the roots and shoots. This fall is a consequence of the reaction of these carbonyl compounds with SO2 in the plant tissue under the formation of bisulphite adducts (-hydroxysulfonic acids), which have been chemically proved and quantitatively estimated.  相似文献   

10.
Summary Fine divided HF-etched quartz was dissolved in a 0.2M solution of pyrocatechol at pH 9.6. Between 17 and 40 °C the dissolution rate (v s ) follows the equation: logv s =0.0295 T-20.87 At 25 °Cv s amounts to 0.8 · 10–12 g cm–2 sec–1. With several phenols the dissolution rate of quartz decreases in the order: pyrocatechol > pyrogallol > 2, 3-dihydroxynaphthalene.  相似文献   

11.
Summary On the basis of nuclear magnetic resonance measurements and in agreement with recently reported mass-spectrometric investigations it is shown that the molecular formulae of Helvolic acid and Cephalosporin P1 must be revised to C33H44O8 and C33H50O8 respectively, and that the additional carbon atom is present as an angular methyl group.A comparison with the data obtained with fusidic acid points to a similarity among the three substances which is closer than hitherto suspected.  相似文献   

12.
The nest cell lining ofHylaeus bisinuatus (Hymenoptera: Colletidae) was shown by high-resolution solidstate [13C]NMR to be composed of lipid polymer and protein. The lipid polymer was shown by reduction and subsequent GC/MS analysis to be comprised of -hydroxy fatty acids (C20, C22, C24 and C26) and fatty alcohols (C16 to C30). The protein portion of the lining had a silk-like amino acid composition.  相似文献   

13.
Acyl-CoA thioesterase (ACOT) activities are found in prokaryotes and in several compartments of eukaryotes where they hydrolyze a wide range of acyl-CoA substrates and thereby regulate intracellular acyl-CoA/CoA/fatty acid levels. ACOT9 is a mitochondrial ACOT with homologous genes found from bacteria to humans and in this study we have carried out an in-depth kinetic characterization of ACOT9 to determine its possible physiological function. ACOT9 showed unusual kinetic properties with activity peaks for short-, medium-, and saturated long-chain acyl-CoAs with highest V max with propionyl-CoA and (iso) butyryl-CoA while K cat/K m was highest with saturated long-chain acyl-CoAs. Further characterization of the short-chain acyl-CoA activity revealed that ACOT9 also hydrolyzes a number of short-chain acyl-CoAs and short-chain methyl-branched CoA esters that suggest a role for ACOT9 in regulation also of amino acid metabolism. In spite of markedly different K ms, ACOT9 can hydrolyze both short- and long-chain acyl-CoAs simultaneously, indicating that ACOT9 may provide a novel regulatory link between fatty acid and amino acid metabolism in mitochondria. Based on similar acyl-CoA chain-length specificities of recombinant ACOT9 and ACOT activity in mouse brown adipose tissue and kidney mitochondria, we conclude that ACOT9 is the major mitochondrial ACOT hydrolyzing saturated C2-C20-CoA in these tissues. Finally, ACOT9 activity is strongly regulated by NADH and CoA, suggesting that mitochondrial metabolic state regulates the function of ACOT9.  相似文献   

14.
Summary A gustatory mutant ofDrosophila melanogaster insensitive to the taste of salt has been isolated. Genetic crosses and a deletion mapping analysis show that this mutation, designatedgust-M 1 is located in the 93C3–6-93D6–7 region of the third chromosome.gust-M 1 is also insensitive to the taste of quinine sulfate. The behavior of this mutant may be explained by assuming thatgust-M 1 could be a mutation perturbing functions in the central nervous system affecting the responses to both compounds.  相似文献   

15.
Summary By condensing 2:4:5-triamino-6-hydroxy-pyrimidine with dihydroxyacetone (diacetate), diaminoacetone or acetone-1,3-di (p-formylaminobenzoic acid) not the expected 8- or 9-oxymethyl resp. -aminomethyl-pteridines but 8-or 9-methyl-pteridines were obtained. With p-tolyl-d-isoglucosamine not a tetrahydroxybutyl-pteridine but a trihydroxybutyl-pteridine was formed. For an explanation of these results it is supposed that from the dihydro-pteridines formed at first by intramolecular splitting off of H2O or R·NH2 aromatization takes place.  相似文献   

16.
Summary The biosynthesis of reserpinine (II) and vincamedine (IVa) in Vinca plants has been investigated with the help of labelled precursors. Incorporation of 1-14C-Sodium acetate into the non-tryptophan C10-moiety of these alkaloids occurred only with extensive randomization of the label. In addition, indications were obtained that the methyl group of methionin is not involved in the formation of this fragment.  相似文献   

17.
Summary Female gametes of the marine brown algaAnalipus japonicus secrete a complex bouquet of olefinic C11-hydrocarbons. The major compound is ectocarpene, while hormosirene and dictyotene are present at levels of 2%. Although a minor constituent of the pheromone bouquet, hormosirene is 100 times more active as a male-attractant than ectocarpene. Thus, sex attraction inAnalipus is mediated by two compounds, which diverge largely in concentration and biological activity.  相似文献   

18.
A possible new role for the anti-ageing peptide carnosine   总被引:5,自引:0,他引:5  
The naturally occurring dipeptide carnosine (β-alanyl-L-histidine) is found in surprisingly large amounts in long-lived tissues and can delay ageing in cultured human fibroblasts. Carnosine has been regarded largely as an anti-oxidant and free radical scavenger. More recently, an anti-glycating potential has been discovered whereby carnosine can react with low-molecular-weight compounds that bear carbonyl groups (aldehydes and ketones). Carbonyl groups, arising mostly from the attack of reactive oxygen species and ow-molecular-weight aldehydes and ketones, accumulate on proteins during ageing. Here we propose, with supporting evidence, that carnosine can react with protein carbonyl groups to produce protein-carbonyl-carnosine adducts (‘carnosinylated’ proteins). The various possible cellular fates of the carnosinylated proteins are discussed. These proposals may help explain anti-ageing actions of carnosine and its presence in non-mitotic cells of long-lived mammals. Received 29 November 1999; accepted 27 December 1999  相似文献   

19.
Zur Kenntnis des Muscarins   总被引:1,自引:0,他引:1  
Summary The alkaloid muscarin was isolated from fly agaric. The analyses of crystallized salts (chloride, tetra-chloroaurate,Reinecke's salt) led to C9H20O2N+ as the simplest formula. The presence of aldehyde and tri-methyl-ammonium groups, which had been assumed hitherto, could not be proved. The quaternary nature of the nitrogen atom was shown. Pharmacological tests on frog heart, rabbit gut and cats show the purely peripheral parasympathomimetic effect of the smallest doses.  相似文献   

20.
Summary The effect of irradiation (500 R) on the cell cycle of the diploid (EATdipl.) and the hypertetraploid (ELT) Ehrlich ascites tumor growing in the peritoneal cavity of male NMRI mice has been studied autoradio-graphically by the double labelling technique (H3- and C14-thymidine) and the method of labelled mitoses. The results suggest that the proliferation kinetics of tumor cells after irradiation depends on the type of tumor cell strain tested. Identical results were obtained after application of the alkylating agent cyclophosphamide (100 mg/kg).  相似文献   

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