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61.
E. Campaigne Homer A. Smith J. S. Sandhu Chung S. Kim 《Journal of heterocyclic chemistry》1983,20(1):55-59
A potential anti-ovulatory agent, 5-methoxy-6-chloro-3-β-acetamidoethylbenzo[b]thiophene, a sulfur analog of melatonin having the 6-position blocked to inhibit oxidative metabolism, has been synthesized from 3-hydroxy-4-chloroacetophenone. 相似文献
62.
A. Berglund T. Buran P.J. Carlson C.J.S. Damerell I. Endo A.R. Gillman V. Gracco R.J. Homer M.J. Hotchkiss A. Lundby M. Macri B.N. Ratcliff A. Santroni T. Tso F. Wickens J.A. Wilson 《Physics letters. [Part B]》1975,57(1):100-104
For the first time, the reactions π+p→K+∑+ and K?p→π?∑+ have been studied in the same apparatus. This has been done at an adequately high momentum (10.1 GeV/c) to allow a check of the prediction of exchange degeneracy, that the differential cross sections should be converging at high energy. We have measured the cross section for momentum transfers t between tmin and t = ?0.3 (GeV/c)2. We find that for both reactions the differential cross section shows an exponential fall, with no deviations right in to t =tmin (where some other experiments have shown a dip in the cross section). Furthermore, we find the magnitude of the differential cross sections to be closely similar at t = 0, with a ratio However, the slope for the positive reaction is about 19% steeper than that for the negative reaction. 相似文献
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Homer RW Swanson J Jilek RJ Hurst T Clark RD 《Journal of chemical information and modeling》2008,48(12):2294-2307
SYBYL line notation (SLN) is a powerful way to represent molecular structures, reactions, libraries of structures, molecular fragments, formulations, molecular queries, and reaction queries. Nearly any chemical structure imaginable, including macromolecules, pharmaceuticals, catalysts, and even combinatorial libraries can be represented as an SLN string. The language provides a rich syntax for database queries comparable to SMARTS. It provides full Markush, R-Group, reaction, and macro atom capabilities in a single unified notation. It includes the ability to specify 3D conformations and 2D depictions. All the information necessary to recreate the structure in a modeling or drawing package is present in a single, concise string of ASCII characters. This makes SLN ideal for structure communication over global computer networks between applications sitting at remote sites. Unlike SMILES and its derivatives, SLN accomplishes this within a single unified syntax. Structures, queries, compounds, reactions, and virtual libraries can all be represented in a single notation. 相似文献
65.
A. Berglund T. Buran P.J. Carlson C.J.S. Damerell I. Endo A.R. Gillman V. Gracco R.J. Homer M.J. Hotchkiss A. Lundby M. Macri B.N. Ratcliff A. Santroni T. Tso F. Wickens J.A. Wilson 《Physics letters. [Part B]》1978,73(3):369-374
For the first time, the line reversed reactions π+p→K+Σ+and K?p→π?Σ+ have been studied in the same apparatus. We present the differential cross sections and polarizations over a large t range and at two momenta, 7.0 and 10.1 GeV/c. The differential cross sections as a function of t are shown for the first time to cross over. Going from the lower to the higher momentum, the differences in cross section between the two reactions diminish at low |t| by about a factor 2. We find large polarizations of opposite sign for the two reactions. The momentum dependence, presented in the form of αeff(t) for the t range 0 to ?2 (GeV/c)2, is compared with the expectations from the K1?K7 trajectory. 相似文献
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Methyl indole-3-acetate undergoes two simultaneous iridium-catalysed borylations to deliver exclusively 2,7-diboronate, with the ligand 3,4,7,8-tetramethyl-1,10-phenanthroline (Me4Phen) pivotal in driving the diborylation to completion. Subsequent oxidation-hydrolysis of the diboronate provides methyl 7-hydroxyoxindole-3-acetate which upon hydrolysis of the ester delivers 7-OH-OxIAA, an antioxidant, endogenous metabolite of indole-3-acetic acid found in various types of corn. This route has an overall yield of 50%, involves a single chromatographic purification and is an efficient alternative to existing syntheses, made possible by executing simultaneous oxidations at the indole C2 and C7 sites. 相似文献
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We examine the exact relation between the superconformal symmetry breaking chiral superfield (X) and the goldstino superfield in microscopic models of an arbitrary Kahler potential (K) and in the presence of matter fields. We investigate the decoupling of the massive sgoldstino and scalar matter fields and the offshell/onshell-SUSY expressions of their superfields in terms of the fermions composites. For general K of two superfields, we study the properties of the superfield X after integrating out these scalar fields, to show that in the infrared it satisfies (offshell) the condition X3=0 and X2≠0. We then compare our results to those of the well-known method of constrained superfields discussed in the literature, based on the conjecture X2=0. Our results can be used in applications, to couple offshell the (s)goldstino fields to realistic models such as the MSSM. 相似文献