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161.
Gerhard Buchbauer Susanne Dominici Helga Christiane Rohner Franz Karner 《Monatshefte für Chemie / Chemical Monthly》1987,118(4):511-519
The synthesis of 3-(3,3-dimethyl-2-exo-norbornyl)-2-methylprop-2-en-1-ol (3) and of 8-hydroxymethyl-8-methylcamphene (4) is described.3 and4 are analogues of -Santalol (1) with the allylic hydroxyl group in a position of two or three carbon atoms closer to the bicyclic nucleus compared to1. 4 is also an analogue to Patchenol® which is used sometimes to blend the patchouli oil. The odour impression of these compounds, of the pureendo-epimer of3, and of theendo-exo-mixture of3 are described and compared with the odour of1 and a further analogue whose synthesis has already been reported in a preceding paper [1].
Auszugsweise vorgetragen auf der gemeinsamen wissenschaftlichen Tagung der ÖPhG und DPhG am 11. September 1986 in Innsbruck. Die Synthese von4 wurde bereits am 15. März 1983 anläßlich des 9th International Congress of Essential Oils in Singapore vorgestellt. 相似文献
162.
Combined biological and chemical assessment of estrogenic activities in wastewater treatment plant effluents 总被引:2,自引:0,他引:2
Aerni HR Kobler B Rutishauser BV Wettstein FE Fischer R Giger W Hungerbühler A Marazuela MD Peter A Schönenberger R Vögeli AC Suter MJ Eggen RI 《Analytical and bioanalytical chemistry》2004,378(3):688-696
Five wastewater treatment plant effluents were analyzed for known endocrine disrupters and estrogenicity. Estrogenicity was determined by using the yeast estrogen screen (YES) and by measuring the blood plasma vitellogenin (VTG) concentrations in exposed male rainbow trout (Oncorhynchus mykiss). While all wastewater treatment plant effluents contained measurable concentrations of estrogens and gave a positive response with the YES, only at two sites did the male fish have significantly increased VTG blood plasma concentrations after the exposure, compared to pre-exposure concentrations. Estrone (E1) concentrations ranged up to 51 ng L–1, estradiol (E2) up to 6 ng L–1, and ethinylestradiol (EE2) up to 2 ng L–1 in the 90 samples analyzed. Alkylphenols, alkylphenolmonoethoxylates and alkylphenoldiethoxylates, even though found at µg L–1 concentrations in effluents from wastewater treatment plants with a significant industrial content, did not contribute much to the overall estrogenicity of the samples taken due to their low relative potency. Expected estrogenicities were calculated from the chemical data for each sample by using the principle of concentration additivity and relative potencies of the various chemicals as determined with the yeast estrogen screen. Measured and calculated estradiol equivalents gave the same order of magnitude and correlated rather well (R
2=0.6).An erratum to this article can be found at 相似文献
163.
Martine Croisy-Delcey Christiane Huel Emile Bisagni 《Journal of heterocyclic chemistry》1988,25(2):661-665
Under the conditions of the Bischler-Napieralski reaction the cyclization of 2-(1,4-dimethoxy and 1,4,8-trimethoxynaphthyl)ethylacetamides derivatives take place essentially at the 1 position by substitution of the 1-methoxy group. Nevertheless, 1-aminomethyl-9,10-azaanthraquinones are accessibles by condensation of 1-aminomethylisoquinoline-5,8-diones with a 1,4-diacetoxy-1,3-butadiene. 相似文献
164.
The total synthesis of spirotryprostatin B, a cytostatic spiro[pyrrolidine-3,3'-oxindole] alkaloid, is described. The key step of the synthetic approach consists of the application of the MgI2-mediated ring-expansion reaction of a spiro[cyclopropane-1,3'-oxindole] with an aldimine, leading to rapid assembly of the spirotryprostatin core. The route documents the installation of the prenyl side chain by Julia-Kocieński olefination of a key aldehyde precursor, a transformation that ultimately allows for facile synthesis of analogues and facilitates structure-activity relationships studies. 相似文献
165.
Manfred Meisel Christiane Donath 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2):451-454
Abstract Under definite conditions the dithiophosphoric acid chloride pyrididium betaine reacts with primary amines, RNH2, yielding four-membered rings. Depending on the electronic properties of R either diaza or thiazadiphosphetines are formed. An elimination-addition mechanism via imido dithiomonometaphosphate is discussed. 相似文献
166.
Jean-Marc Heuchel Sébastien Albrecht Christiane Strehler Albert Defoin Céline Tarnus 《Tetrahedron: Asymmetry》2012,23(20-21):1467-1473
Cyclopentadiene nitroso adducts 1a and ent-1a were synthesised in good yields and good enantiomeric excess from chiral chloro-nitroso derivatives 4 and 5 in the d-mannose and d-ribose series, respectively. The thermal racemisation of these adducts occurred below room temperature. Some other chiral Diels–Alder nitroso adducts were prepared in the d-mandelic, l-prolinol and d-O-methylprolinol series and their thermal isomerisation was specified according to the N-substitution. A simple synthesis of the chiral amido-cyclopentenol (+)-2b, an important precursor for biological interesting compounds, is presented from ent-1a. 相似文献
167.
168.
The combination of electron paramagnetic resonance (EPR) and mass spectrometry (MS) was used as an efficient tool to elucidate the mechanism of an ene-reaction between a dienol compound and 2-methyl-2-nitrosopropane. 相似文献
169.
Jason Painter M. Gail Jones Thomas R. Tretter Dennis Kubasko 《School science and mathematics》2006,106(4):181-190
Although there have been numerous scientists‐in‐the‐classroom initiatives in recent years, there is little research that documents whether or not these initiatives make an impact on students. This study examined 27 seventh‐grade and 27 tenth‐grade students' perceptions of scientists before and after a weeklong educational experience on nanotechnology, where students interacted with scientists. The data from this project included student interviews (pre and post intervention), field notes, student stories, and follow‐up interviews conducted 1 year after the project. Results showed that fewer than 10% of participants reported ever interacting with scientists in school settings prior to this project, despite attending schools in areas surrounded by a high density of scientists. Students' perceptions of scientists changed as a result of the project. The implications for science instruction are discussed. 相似文献
170.
Rik Van Deun Peter Nockemann Tatjana N. Parac-Vogt Kristof Van Hecke Luc Van Meervelt Christiane Grller-Walrand Koen Binnemans 《Polyhedron》2007,26(18):5441-5447
The near-infrared luminescence properties of three (E)-N-hexadecyl-N′,N′-dimethylamino-stilbazolium tetrakis(1-phenyl-3-methyl-4-benzoyl-5-pyrazolonato) lanthanide(III) complexes are described. These three complexes, containing trivalent neodymium, erbium and ytterbium, respectively, show near-infrared luminescence in acetonitrile solution upon UV irradiation. Luminescence decay times have been measured. The complexes consist of a positively charged hemicyanine chromophore with a long alkyl chain and a tetrakis(pyrazolonato) lanthanide(III) anion. Because of the absence of an -hydrogen atom in the pyrazolonato ligands, and because of the saturation of the coordination sphere by four bidentate ligands, the luminescence properties are enhanced when compared to, e.g. quinolinate complexes. 相似文献