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61.
The reaction of 2-phenyl- and 1-methyl-2-phenylindole with nitrogen dioxide or with nitrous acid (NaNO2-CH3COOH) in benzene leads mainly to the formation of the isonitroso and 3-nitroso indole derivatives, respectively. When reacted with nitrous acid, 1-methyl-2-phenylindole gives also the corresponding azo-bis-indole in good yields. The reaction of indole with nitrogen dioxide leads to 2-(indol-3-yl)-3H-indol-3-one as the main product together with small amounts of 2-(indol-3-yl)-3H-indol-3-oxime; whereas the major product obtained when the same indole is reacted with nitrous acid is represented by 2-(indol-3-yl)-3H-indol-3-oxime. The reaction of 3-alkyl substituted indoles with nitrogen dioxide is rather complex and results in the formation of different nitro indoles, whereas nitrosation is observed when nitrous acid is used. Crystal structures of 2-(indol-3-yl)-3H-indol-3-one and of 4-nitro-N-acetyltryptamine have been determined by X-ray analysis. 相似文献
62.
63.
A simple and efficient stereoselective synthesis of polysubstituted beta,gamma-epoxyhydroxylamines and 4-hydroxyalkyl-1,2-oxazetidines, based on the addition of alpha-lithiated aryloxiranes to nitrones and subsequent cyclization of the corresponding intermediates in a 4-exo-tet mode, is described. 相似文献
64.
Corrado Marastoni 《Mathematische Nachrichten》2013,286(10):992-1006
Given a pair of dual generalized flag manifolds of a semisimple algebraic group, we show that the integral transform between them given by the open orbit in their product is an equivalence. We also describe the links of this problem with the structure of generalized Verma modules, and how the above construction can be applied to the representation theory of real forms of the group. 相似文献
65.
Journal of Algebraic Combinatorics - A class of scattered linearized polynomials covering infinitely many field extensions is exhibited. More precisely, the q-polynomial over $${{\mathbb... 相似文献
66.
Alessia Bacchi Giorgio Chelucci Manlio Grandino Giovannina Minardi Corrado Pelizzi Giancarlo Pelizzi Costantino Solinas 《Journal of chemical crystallography》1994,24(10):659-663
Cobalt(II), nickel(II), and copper(II) complexes of 2-[(2S)-2-pyrrolidinyllpyridine (L) have been synthesized and characterized. The crystal structure of the complex [Cu(L)2(NO3)]NO3 has been determined by X-ray diffraction. Crystals are monoclinic, space groupP2+, witha=10.766(3).b=7.525(2),c=13.447(4) Å. =104.64(2)°. and Z=2. The structure consists of [Cu(L)2(NO3)]+ cations and NO
3
t-
anions. The copper atom has a distorted trigonal bipyramidal coordination geometry with the two pyrrolidine nitrogens and one nitrate oxygen occupying the equatorial positions and the two pyridine nitrogens at the apices. The crystalline cohesion is ensured by a network of hydrogen bonds involving the pyrrolidine groups as donors and both coordinate and uncoordinate nitrates as acceptors. 相似文献
67.
68.
Lucedio Greci Mirco Pieroni Giorgio Tosi Corrado Rizzoli Paolo Sgarabotto Franco Ugozzoli 《Journal of chemical crystallography》1991,21(6):693-699
Methyl and methoxy substituted nitroarenes were reacted with acethophenone in the presence of sodium ethoxide in ethanol giving arylamino-conjugated diketo derivatives. A case ofipso-substitution of a methoxy group is discussed. The title compound C23H19NO2 (M
r
=341.4) crystallizes in the monoclinic system, space groupP21/n witha=21.579(4),b=8.526(2),c=9.983(2) Å;=92.3(1)°;V=1835.2(7) Å3,Z=4,D
c
=1.24 g cm–3,(Cu-K
)=5.9 cm–1, =1.5418 Å,F(000)=720. The molecule adopts theE configuration with the C=O carbonyl groupstrans with respect to the ethylenic double bond. 相似文献
69.
Gabriele Bocelli Gianluca Calestani Corrado Rizzoli 《Journal of chemical crystallography》1990,20(3):217-221
Crystals of the title compound are monoclinic (C26H25NO): space groupP21/c,a=16.565(3),b=10.328(2),c=12.621(3) Å,=104.02(3)°. The structure was solved by direct methods and refined by block-matrix least-squares to giveR=0.056 andR
w
=0.061 for 1613 reflections above 2(I). The amide moiety is tilted by 19.3(2)° with respect to the mean aromatic ring plane. The two othergem phenyl rings subtend a dihedral angle of 112.2(4)° to each other. The molecules are joined in the solid by N-HO hydrogen bonds. 相似文献
70.
A fast ion chromatographic method with suppressed conductivity detection has been developed for the simultaneous determination of methane-, ethane-, 1-propane-, 1-butane-, 1-pentane-, 1-hexane-, 1-heptane-, 1-octane-, 1-nonane-, 1-decane-, 1-dodecane-, dodecylbenzene-, p-toluene-, benzenesulfonic acids, octylsulfate and dodecylsulfate in water samples. Due to the high number of analytes and their heterogeneity, the effect of the mobile phase parameters (NaOH, CH(3)OH and CH(3)CN concentration) on the retention factors has been studied in detail, so achieving, for the first time, the separation among 15 of these analytes by a gradient elution. Detection limits included within 0.06-0.16 microM have been obtained. Interferences from Cl(-), NO(3)(-) and SO(4)(2-), possible anions present in water samples, have been considered and a SPE procedure has been developed for analytes enrichment and matrix removal in a seawater sample. This is the first application of an ion-exchange chromatographic method to a seawater sample for this kind of analytes. 相似文献