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1.
The isolation of N-quinaldyl-L-arginine·HCl (1) from the CoccinellidaeSubcoccinella-24-punctata is reported. The structure, first established on the basis of the analysis of the spectral properties of1, has been confirmed by synthesis. The alkaloid is of endogenous origin and markedly deterrent to ants.  相似文献   

2.
Summary The structure 3-butyl-5-propylindolizidine (2), tentatively assigned to a minor alkaloid in skin extracts from a number of poison frogs of the Neotropical genusDendrobates, has been confirmed and its stereochemistry determined as 5E, 9E (2d) by comparison on GC and GC-MS with the four synthetic diastereomers2a-2d.  相似文献   

3.
Summary The blood of the Mexican bean beetle (Epilachna varivestis) contains a homotropane alkaloid, euphococcinine (1). The beetles reflex bleed when disturbed, thereby deploying the alkaloid, which is provenly deterrent to spiders and ants. Newly emerged adults lack the alkaloid, but the compound builds up to deterrent levels in their blood within days. Eggs and larvae ofEpilachna are devoid of the compound.Paper No 79 of the series: Defense Mechanisms of Arthropods. Study supported by NIH (Grants AI-02908 and AI-12020) and Hatch Funds (NYC-191409). We thank G. Eidens, K. Hicks, and M. Eisner for excellent technical help, and an anonymous reviewer for calling two critical references to our attention. The ant tests were done at the Archbold Biological Station, Lake Placid, Florida. The hospitality of the Fogarty Scholar-in-Residence Program (to J.M.) is acknowledged with pleasure.  相似文献   

4.
Summary A bromine-containing alkaloid, oxysceptrin, has been isolated as a potent actomyosin ATPase activator from the Okinawan marine spongeAgelas cf.nemoechinata, and the structure elucidated to be1 on the basis of the 2D NMR spectral data.Acknowledgments. We thank Mr Z. Nagahama for his help in sponge collecting and Ms M. Takamatsu for her technical assistance.  相似文献   

5.
Summary A new bromotyrosine-derived alkaloid with antileukemic activity, purealidin A (5), has been isolated from the Okinawan marine spongePsammaplysilla purea and its chemical structure elucidated on the basis of the spectroscopic data.  相似文献   

6.
Zur Stereochemie der Propandioldehydrase-Reaktion   总被引:2,自引:0,他引:2  
Summary Propanedioldehydrase is shown to convert both (+)-(S)-2-2H-propanediol,3, and (–)-(R)-1-2H2-propanediol,5, to specimens of deuterated propion-aldehyde, for which the (S)-configuration has been established. Thus, in the propanedioldehydrase reaction migration of hydrogen atoms from C–1 to C–2 always occurs with inversion of configuration.  相似文献   

7.
Summary The phenylpropylamine fraction ofCatha edulis FORSK. grown in Kenya has been investigated. The major components have been found to be (S)-(–)--aminopropiophenone (1), (+)-norpseudoephedrine (2) and(–)-norephedrine (3). Quantitative ratios of1, 2, 3 in tissues of different age are discussed.
ZNS-aktive Phenylpropylamine vonCatha edulis FORSK. (Celastraceae) kenyanischer Herkunft
  相似文献   

8.
Summary A novel bromine-containing alkaloid, hymenin, has been isolated from the Okinawan marine spongeHymeniacidon sp. as a potent -adrenoceptor blocking agent and its structure determined to be1 on the basis of the spectral data.  相似文献   

9.
Summary Syntheses of 4-methylspiro [4.5]deca-6, 9-diene-2, 8-dione (IIb) and 1,4-dimethylspiro [4.5]deca-6, 9-diene-2, 8-dione (IIc) by spiranation of phenolic diazoketones (Ib) and (Ic) respectively are reported. Formation of (IIc) illustrates the first aryl participation of phenolic diazoketone prepared from higher homologue of diazomethane.  相似文献   

10.
Summary The absolute configuration of a novel chiral neuroleptic agent SU 23397 (I) was determined by ORD comparison of (+)-5-methoxy dihydro coumarilic acid (VIII), a synthetic precursor of SU 23397 (I), with (+)-dihydro coumarilic acid, whose absolute configuration is known9. This assignment was confirmed by oxidative degradation of (+)-5-methoxy dihydro coumarilic acidVIII tod-(+)-malic acid.Acknowledgments. We wish to acknowledge and thank Dr J. Karliner, Ciba-Geigy Corporation, Ardsley, New York, for the ORD curves. We thank Dr Max Wilhelm for support and encouragement.  相似文献   

11.
Summary Thein vitro anti-acetylcholinesterase properties ofbis-(dimethylamino-3-phenoxy)-1-3 propane dimethiodide (2842 CT) of two phenolics derivatives (3443 CT and 3116 CT) and of the two corresponding carbamic esters (3152 CT et 3113 CT) have been compared using human red blood corpuscles as enzyme source; under specified conditions, the Cl-50 are respectively 8 × 10–7 M for 2842 CT, 3.5 × 10–9 for the two phenolic compounds, and 1.5 × 10–9 for the carbamic esters. The potencies of these phenols are very close to those of the carbamates, being a bit higher or lower depending on the concentration of the inhibitor and on the time of the readingThe two phenolic compounds, like 2842 CT, react readily with the enzyme contrarily to the carbamic esters which combine slowly. On the other hand the inhibition by the phenolic derivatives is as stable against washing as that by the carbamates. The carbamates, but not the phenols, show the slow displacement phenomenon.Some of these characteristics are compatible with the hypothesis that carbamic compounds could act through liberated phenolic functions but others indicate that carbamic groups have a role of their own.  相似文献   

12.
Summary Anthranilic acid-(14COOH) was administered to rooted leaves ofAdhatoda vasica Nees. The isolated alkaloid peganine = vasicine was degraded according to the method ofSpäth andHikawitz (Figure). The anthranilic acid obtained showed the same specific radioactivity as the alkaloid. Therefore anthranilic acid must be regarded as a direct precursor of peganine inA. vasica Nees.  相似文献   

13.
The composition of the Dufour gland of the antC. scutellaris has been reinvestigated by gas chromatography/mass spectrometry. The major components of the gland are (2E,5E,12Z)-4-oxoheneicosa-2,5,12-trien-1-ol acetate (1a) its 14 and 16 double bond isomers (1b and1c), and the corresponding (Z,Z)-dienes5a and5b, all containing an acetylated C21 chain. The previously proposed structures1d, 1e, and5c, which are based on an homologous acetylated C23 chain, correspond to minor derivatives present in the gland. Traces of acetylated C19 homologs, tentatively identified as1g-1i, have also been found. The Dufour gland contents of the two other EuropeanCrematogaster species have also been studied.C. auberti is very similar toC. scutellaris in producing mainly1a, 1b and1c, together with the same higher and lower homologs, but it lacks the dienic derivatives5, whereasC. sordidula contains essentially the acetylated C19 compounds1g, 1h, and1i, accompanied by acetylated C17 homologs.  相似文献   

14.
Summary Aspartate-3-C14 (XIII) was administered to young plants ofAdhatoda vasica Nees. After a feeding period of 1 or 2 days, the isolated alkaloid peganine (=vasicine) (I) was degraded. The distribution of the radioactivity in the anthranilic acid (II) and glycine (XIV) obtained has been determined (Figure). Most of the radioactivity (80%) was localized in the glycine corresponding to the positions 1 and 2 of peganine. More radioactivity was recovered from position 2 of the alkaloid than from position 1. The labelling pattern is discussed. The results indicate either that aspartate or a closely related compound is an immediate precursor of peganine.  相似文献   

15.
Enantiomeric cannabinoids: stereospecificity of psychotropic activity   总被引:1,自引:0,他引:1  
Summary The 1,1-dimethylheptyl homolog of (–)-(3R,4R)-7-hydroxy-delta-6-tetrahydrocannabinol (compoundII) is highly psychotropic in mice, rats and pigeons. The (+)-(3S,4S) enantiomer (III) was found to be psychotropically inactive at doses up to several thousand times those of the ED50 of (II).We thank Dr A. Breuer and Mrs H. Amsalem for help with the syntheses. The research reported above was supported in Tucson by NIH grant NS 15441; in Uppsala by grants from the Swedish Medical Research Council (5757) and the Swedish Council for the Planning and Coordination of Research (84/2082); in Jerusalem by the Szold Foundation.Presented in part at a meeting at the US National Institute on Drug Abuse, Washington, D.C., October 1986, see NIDA Research Monographs79 (1987) 15.  相似文献   

16.
Summary (1 R) [1-3H,2H1] 3-Phenylpropanol, the key intermediate in the synthesis of (4 R) [4-3H,2H1] D, L-homoserine and of the (4 S)-isomer, is obtained from (1 S) [1-2H1] 3-phenylpropanol and (1 RS) [1-3H] ethanol upon incubation with yeast alcohol dehydrogenase and NAD+; under similar conditions 2-phenylethanol undergoes very small exchange with [1-2H2] ethanol.  相似文献   

17.
A highly potent attractant of zoospores ofAphanomyces cochlioides, a causal fungus of the root rot disease of spinach (Spinacia oleracea), was isolated from spinach roots, and its structure was determined by spectroscopic evidence and chemical synthesis as cochliophilin A (5-hydroxy-6,7-methylenedioxyflavone,1). A chromosorb particle prepared by soaking in solution of1 showed a potent attracting activity toward the zoospores using concentrations of1 above 10–9 or 10–10 M.  相似文献   

18.
Summary Five unusual amino acids were identified as antimutagens against spontaneous mutation ofSalmonella typhimurium TA100: L-azetidine-2-carboxylic acid (1) from Liliaceae plants, -(methylenecyclopropyl)glycine (2) fromLitchi chinensis seeds, and 2-amino-4-methylhex-5-ynoic acid (3), hypoglycin A (4), and (2S, 4R)-2-amino-4-hydroxyhept-6-ynoic acid (5) fromEuphoria longana seeds. The absolute stereochemistry of5 was determined by its chiral synthesis from L-allylglycine, proving that5 is the C-4 epimer of the amino acid previously isolated from dried longan seeds.This work was partly supported by a Grant-in-Aid form the Ministry of Education, Science, and Culture, Japan, No. 57740283 (to HK).  相似文献   

19.
Summary Polygodial (1), the defense metabolite stored in the skin of the nudibranchDendrodoris limbata, is toxic for the mollusc itself when injected into the hepatopancreas. Biosynthetic experiments using labeled mevalonic acid were devised to investigate a possible metabolic relationship between1 and the mixture of sesquiterpenoidic esters2, stored in the hepatopancreas. The results suggest that1 and2 are biosynthesized by independent pathways.Thanks are due to G. Villani for supplyingDendrodoris limbata and to A. Trabucco for technical assistance.  相似文献   

20.
Separation of a lipophilic extract of the bryozoan,Dakaira subovoidea, a common fouling organism of underwater structures, guided by inhibition of lipid peroxide formation in rat liver microsomes, gave 5,7-dihydroxy-1-hydroxymethyl-6-oxo-6H-anthra[1,9-bc]thiophene (1a) and its 1-methoxycarbonyl derivative (1c), together with the known 1,8-dihydroxyanthraquinone (2). The structures were determined by spectral and crystallographic analyses.  相似文献   

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