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991.
You Zi Markus Lange Constanze Schultz Ivan Vilotijevic 《Angewandte Chemie (International ed. in English)》2019,58(31):10727-10731
Latent nucleophiles are compounds that are themselves not nucleophilic but can produce a strong nucleophile when activated. Such nucleophiles can expand the scope of Lewis base catalyzed reactions. As a proof of concept, we report that N‐silyl pyrroles, indoles, and carbazoles serve as latent N‐centered nucleophiles in substitution reactions of allylic fluorides catalyzed by Lewis bases. The reactions feature broad scopes for both reaction partners, excellent regioselectivities, and produce enantioenriched N‐allyl pyrroles, indoles, and carbazoles when chiral cinchona alkaloid catalysts are used. 相似文献
992.
A response-plane has been developed with Tetrahymena pyriformis population growth impairment toxicity data [log 1/50% growth inhibitory concentration (IGC50)], the 1-octanol/water partition coefficient (log Kow), and the energy of the lowest unoccupied molecular orbital (Elumo). A statistically robust plane [log 1/IGC50 = 0.530 (log Kow) -0.890 (Elumo) -0.271, n = 50, s = 0.295, r2 = 0.855, F = 145] was found for reactive carbonyl-containing aliphatic chemicals. These compounds had a variety of electrophilic mechanisms of action and included aldehydes acting as Schiff-base formers, alpha,beta-unsaturated aldehydes and alpha,beta-unsaturated ketones acting as Michael-type acceptors, and selected alpha-diones acting as selective binders to arganine residues; gamma-diones acting as selective binders to tubulin; and beta-diones with unknown mechanisms of action. Outliers to this model broadly fell into two groups: small reactive molecules (e.g., acrolein) that were more toxic than predicted and molecules in which the reactive center was sterically hindered by an alkyl group (e.g., 2,4-dimethyl-2,6-heptadienal) that were less toxic than predicted. 相似文献
993.
994.
H. P. Röser M. Yamanaka R. Wattenbach G. V. Schultz 《International Journal of Infrared and Millimeter Waves》1982,3(6):839-868
A complete theory for waveguide laser modes for oversized metallic and dielectric waveguides with circular cross section has been developed for the submm wavelength region. The experimental investigations have been done by a submm heterodyne technique for the first stage using a Schottky barrier diode in an open structure mixer. 相似文献
995.
We clarify the parameterization of the probability of transverse conduction electron spin relaxation. ?, at the surface of a metal. Using Walker's boundary condition on the transverse spin magnetization, we have calculated the ? and thickness dependence of the spin resonance linewidth. The results are discussed in simple physical terms. The recent work of Allam and Vigouroux is shown to contain errors. 相似文献
996.
997.
Schäffler S. Schultz R. Weinzierl K. 《Journal of Optimization Theory and Applications》2002,114(1):209-222
We propose a new stochastic algorithm for the solution of unconstrained vector optimization problems, which is based on a special class of stochastic differential equations. An efficient algorithm for the numerical solution of the stochastic differential equation is developed. Interesting properties of the algorithm enable the treatment of problems with a large number of variables. Numerical results are given. 相似文献
998.
Brian N. Figgis Alexandre N. Sobolev Arthur J. Schultz Philip A. Reynolds 《Acta Crystallographica. Section C, Structural Chemistry》2001,57(10):1151-1153
The crystal structure of the title compound, [ReCl4(C8H10N2)2], has been determined by X-ray diffraction at 11 K and by neutron diffraction at 20 K. The accurate and extensive data sets lead to more precise determinations than are available from earlier work. The agreement in atomic positional and displacement parameters at these very low temperatures is good. The results will facilitate re-examination of the magnetic structure of the complex. The Re atom lies on a special position and the molecule has twofold crystallographic symmetry. 相似文献
999.
1000.
Multifunctional Antibody Agonists Targeting Glucagon‐like Peptide‐1, Glucagon,and Glucose‐Dependent Insulinotropic Polypeptide Receptors 下载免费PDF全文
Dr. Ying Wang Dr. Jintang Du Dr. Huafei Zou Dr. Yan Liu Yuhan Zhang Jose Gonzalez Elizabeth Chao Lucy Lu Pengyu Yang Holly Parker Dr. Van Nguyen‐Tran Dr. Weijun Shen Dr. Danling Wang Dr. Peter G. Schultz Dr. Feng Wang 《Angewandte Chemie (International ed. in English)》2016,55(40):12475-12478
Glucagon‐like peptide‐1 (GLP‐1) receptor (GLP‐1R), glucagon (GCG) receptor (GCGR), and glucose‐dependent insulinotropic polypeptide (GIP, also known as gastric inhibitory polypeptide) receptor (GIPR), are three metabolically related peptide hormone receptors. A novel approach to the generation of multifunctional antibody agonists that activate these receptors has been developed. Native or engineered peptide agonists for GLP‐1R, GCGR, and GIPR were fused to the N‐terminus of the heavy chain or light chain of an antibody, either alone or in pairwise combinations. The fusion proteins have similar in vitro biological activities on the cognate receptors as the corresponding peptides, but circa 100‐fold longer plasma half‐lives. The GLP‐1R mono agonist and GLP‐1R/GCGR dual agonist antibodies both exhibit potent effects on glucose control and body weight reduction in mice, with the dual agonist antibody showing enhanced activity in the latter. 相似文献