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91.
92.
Ella C. Clement 《Tetrahedron letters》2005,46(21):3633-3635
We describe an efficient synthesis of enantiopure tetrahydro-1,4-benzodiazepine-3-ones derived from l-alanine. Diverse substitution at N1, N4, and C10 can be achieved by coupling various N-alkyl derivatives of l-alanine and N-allyl-(2-fluoro-5-nitro)benzylamine. Cyclization of this intermediate proceeds in high yield and without racemization, providing diversity at N1. The NO2 group was easily transformed into other functional groups or removed, providing diversity at C10. Finally, oxidative deallylation allows diverse substitution to be installed at N4. 相似文献
93.
B. Mears P. R. Pine H. W. Doughty B. Freeman J. Guzmán A. Rancano T. L. Kelley J. J. Melloy H. A. Fales T. Callan R. T. P. Jones B. Tougarinov H. Hölemann C. Frick H. Engemann A. Schleicher W. T. Schrenk Ph. H. Delano J. L. Merrill A. S. Russell S. W. Rowell K. S. Jackson N. H. Furman M. I. Schubin K Anderson H. Swett Ella M. Collin H. J. S. Sand L. F. Yntema D. D. Peirce 《Analytical and bioanalytical chemistry》1932,87(5-6):214-224
94.
H. J. S. Sand A. Fischer A. Schleicher A. Lassieur W. F. Munn O. W. Holmes A. Classen A. Hollard Ella M. Collin P. S. Tutundžić A. D. Melaven Ch. M. Craighead W. Böttger C. Harries W. Ostwald W. D. Treadwell A. Coehn L. W. Strock H. S. Luckens M. O. Charmandarjan B. J. Perwuschin W. C. Blasdale A. Glazunow M. Rabinowitsch A. S. Fokin A. Belák Z. v. Alföldy J. H. Hildebrand Th. P. Mc Cutcheon C. H. Herty G. R. Fitterer W. E. Marshall F. Foerster K. Klemm J. Fischer K. Gäbler J. W. Springer H. L. Matthijsen A. Jílek J. Lukas J. Švéda R. Uzel 《Analytical and bioanalytical chemistry》1931,83(3-4):124-143
95.
Borchert H Borchert Y Kaichev VV Prosvirin IP Alikina GM Lukashevich AI Zaikovskii VI Moroz EM Paukshtis EA Bukhtiyarov VI Sadykov VA 《The journal of physical chemistry. B》2005,109(43):20077-20086
Nanostructured ceria doped with other rare earth elements is a good oxygen ion conductor, which gives rise to various catalytic applications such as the construction of membranes for syngas production by partial oxidation of methane. This article focuses on the Gd-doped cerium dioxides, which can be modified with Pt or Pd to enhance the reactivity of the lattice oxygen in interaction with methane. The aim of the work is the elucidation of correlations between the structural, electronic, and chemical properties of these nanomaterials. Detailed studies were performed for a series of samples with and without surface modification by noble metals using a complex combination of physicochemical methods: XRD, TEM, CH(4) TPR, XPS, SIMS, and FTIR spectroscopy of adsorbed CO. XPS and TPR data revealed that surface modification with noble metals enhances the reducibility of the doped ceria support, where the effect is more pronounced for Pd than for Pt. The formation of highly cationic Pd species due to strong metal support interactions provides a possible explanation for this behavior. Furthermore, the results obtained in the present work for the Gd-doped ceria system are compared to those obtained previously for the Pr-doped ceria system. 相似文献
96.
For a system of functional differential equations of an arbitrary order the conditions are established for the initial value problem to be solvable on an infinite interval, and the structure of the set of solutions to this problem is studied. 相似文献
97.
98.
99.
Meinholz MM Carl E Kriemen E Stalke D 《Chemical communications (Cambridge, England)》2011,47(39):10948-10950
In this communication we present the synthesis of the inverse crown ether complex [Li(2)O(2)·Li(4){CH(2)(N(Me)CH(2)S(NtBu)(2))(2)}(2)] (1) which is able to accommodate peroxide in a torus of lithium ions. 相似文献
100.
Gregory B. Kharas Xue Tian Traci A. Ackron Michael H. Akroush Kelly A. O'brien Ella Ostrovskaya 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(3):243-247
Electrophilic trisubstituted ethylene monomers, halogen ring‐substituted 2‐cyano‐N,N‐dimethyl‐3‐phenyl‐2‐propenamides, RC6H4CH [dbnd]C(CN)CON(CH3)2 (where R is 2‐Br, 3‐Br, 4‐Br, 2‐Cl, 3‐Cl, 4‐Cl, 2‐F, 3‐F, 4‐F), were synthesized by potassium hydroxide catalyzed Knoevenagel condensation of ring‐substituted benzaldehydes and N,N‐dimethyl cyanoacetamide, and characterized by CHN elemental analysis, IR, 1H‐ and 13C‐NMR. Novel copolymers of the ethylenes and styrene were prepared at equimolar monomer feed composition by solution copolymerization in the presence of a radical initiator, ABCN at 70°C. The composition of the copolymers was calculated from nitrogen analysis, and the structures were analyzed by IR, 1H and 13C NMR, GPC, DSC, and TGA. High T g of the copolymers in comparison with that of polystyrene indicates a substantial decrease in chain mobility of the copolymer due to the high dipolar character of the trisubstituted ethylene monomer unit. The gravimetric analysis indicated that the copolymers decompose in the 300–450°C range. 相似文献