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991.
Two new dibenzyltin bisditiocarbamates(PhCH2)2 Sn(S2CNEt2)2(1) and (PhCH2)2 Sn(S2CNC4H8)2(2) were synthesized by the reaction of dibenzyltin dichloride with dithiocarbamates and characterized by elemental analysis ,IR,^1H NMR and MS spectra.The crystal structures were determined by X-ray single crystal diffraction analysis.In both complexes,the tin atom is six-coordinated in a distorted octahedral configuration.In the crystals of 1,the molecular packing in unit cell reveals that the two adjacent molecules are symmetrically linked to each other in dimers by two Sn S interactions of 0.3816nm.In the crystals of 2,the molecules are packed in the unit cell in one-dimensional chain structure linked by weaker intermolecular S S conmtacts. 相似文献
992.
XiLIFENG 《高校应用数学学报(英文版)》1997,12(4):483-492
For real-valued functions defined on Cantor triadic ,set. a derivative with corresponding formula of Newton-Leihniz‘s type is given In particular, for the self-simltar functions and alter-nately jumping functions defined in this paper, their derivative and exceptional sets are studied ac-curately by using ergodic theory on Е2 and Duffin-Scbaeffer‘s theorem coneerning metric diophan-tine approximation. In addition, Haar basis of L2(Е2) is constructed and Flaar expansion of stan-drd self-similar function is given. 相似文献
993.
Baran Sándor Pap Gyula Van Zuijlen Martien C. A. 《Statistical Inference for Stochastic Processes》2004,7(3):279-304
A shifted Wiener sheet is observed above a decreasing curve Γ. By the help of a direct discrete approach and under weaker
assumptions than in the paper of Arató [Comput. Math. Appl.
33 (1997), 13–25], an explicit formula is derived for the maximum likelihood estimator of the shift parameter. This estimator
is a weighted linear combination of the values at the endpoints of the curve Γ and weighted integrals of the observed process
and its normal derivative along the curve Γ.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
994.
本文讨论拟微分算子象证的Witt乘积与C[x]▲△A.G[p]的乘积之间的关系,得到以下结果:具有Witt乘积的象证类S1.0^m。是具有普通乘积的函数类S1.0^m经过对Hopf代数的乘积量子化得到的,进一步,给出了C[x]▲△h.cC[p]上标准的辫导数的显示表示,并且证明了其上的Poisson括号与经典的具有同一形式. 相似文献
995.
The structure of (+)1-(3-allylpropyl)-(5R,8S,10R)-N,N-diethyl-N-[6-methylergolin-8-yl]urea, C22H33N4O (allyl-terguride), has been determined as part of a study on the chiral recognition mechanism of ergot alkaloids when they are used as the chiral stationary phase for the separation of racemic mixtures in liquid chromatographic methods. At the pH of the solution used for the crystallization, the molecules of allyl-terguride are protonated at N(6). All bond distances and angles are in the expected ranges. In the asymmetric unit one hydroxide ion is present. Hydrogen bonds join molecules of allyl-terguride in pairs along the b axis, connecting O(2) of the hydroxide ion to O(1) of one molecule and to N(2) and N(6) of another. 相似文献
996.
Summary Characteristics of silica gel dynamically modified with a bile acid derivative have been investigated in liquid chromatography. 3-[(3-cholamidopropyl) dimethylamonio]-1-propane-sulfonate (CHAPS) is selected as modifier. CHAPS possesses a quaternary ammonium group which can be attached to the silica gel surface by cation exchange. The stationary phase modified with CHAPS has been applied to the separation of 1,1-binaphthyl-2,2-diyl-hydrogen phosphate enantiomers.Dedicated to Professor Leslie S. Ettre on the occasion of his 70th birthday. 相似文献
997.
998.
Synthesis of (S)-2-Ethoxy-3-Phenylpropanoic Acid Derivatives and Their Insulin-Sensitizing Activity 总被引:1,自引:0,他引:1
A series of (S)-2-ethoxy-3-phenylpropanoic acid derivatives were synthesized and their insulin-sensitizing activities were evaluated in 3T3-L1 cells. Compounds 1b, 1d, 1e and 1f exhibited more potent insulin-sensitizing activity than rosiglitazone. 相似文献
999.
1000.
Supichar Chokpaiboon Panida Unagul Sutichai Nithithanasilp Somjit Komwijit Wiwat Somyong Thanawut Ratiarpakul 《Natural product research》2018,32(2):149-153
Two salicylaldehyde derivatives (1 and 2), a hydroxymethylphenol (3), five dihydroisobenzofuran (4–8) derivatives, and a 5-chloro-3-deoxyisoochracinic acid (9), together with a known 3-deoxyisoochracinic acid (10) were isolated from the marine fungus Zopfiella marina BCC 18240 (or NBRC 30420). The structures of these compounds were elucidated by extensive spectroscopic analysis. Compound 1 showed weak antituberculous activity against Mycobacterium tuberculosis H37Ra, and antibacterial activity against Bacillus cereus with MIC values of 25 and 12.5 μg/mL, respectively. 相似文献