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161.
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
162.
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
163.
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
164.
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
165.
166.
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
167.
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
168.
This article presents a brief review of correlation schemes which relate ionization energies, ionic heats of formation, proton affinities and heterolytic bond strengths with some simple property of the ion, most commonly its size. The schemes reviewed here have mainly been developed for homologous series and simple atom or group substitutions at charge-bearing sites. The utility of such schemes is illustrated by appropriate examples. 相似文献
169.