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991.
Stephan Ritter 《Physik in unserer Zeit》2011,42(4):166-167
992.
Aurelia Bouchez Adam Walters Holger S.P. Müller Matthias Ordu Frank Lewen Monika Koerber Sandrine Bottinelli Christian P. Endres Stephan Schlemmer 《Journal of Quantitative Spectroscopy & Radiative Transfer》2012,113(11):1148-1154
The rotational spectra of the two monosubstituted 13C isotopologues of the anti conformer of ethanol have been measured between 80–800 GHz using three different spectrometers at the Cologne Laboratory Astrophysics group. The dataset was constrained for fitting with a standard Watson-S reduction Hamiltonian by rejecting transitions from high-lying states showing significant perturbation with the gauche states and by averaging some small methyl torsional splits. This treatment is compatible with the needs for a first astrophysical research for which an appropriate set of predictions is given. 相似文献
993.
Lauren E. Longobardi Dr. Timothy C. Johnstone Rosalyn L. Falconer Dr. Christopher A. Russell Prof. Dr. Douglas W. Stephan 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(36):12665-12669
The hydroboration of phosphaalkynes with Piers’ borane (HB(C6F5)2) generated unusual phosphaalkenylboranes [RCH=PB(C6F5)2]2 that persisted as dimers in both solution and the solid state. These P2B2 heterocycles underwent ring opening when subjected to nucleophiles, such as pyridine and tert‐butylisocyanide, to yield monomeric phosphaalkenylborane adducts RCH=PB(C6F5)2(L). DFT calculations were performed to probe the nature of the interaction of phosphaalkynes with boranes. 相似文献
994.
Total Synthesis of Δ12‐Prostaglandin J3: Evolution of Synthetic Strategies to a Streamlined Process 下载免费PDF全文
Prof. Dr. K. C. Nicolaou Dr. Kiran Kumar Pulukuri Ruocheng Yu Dr. Stephan Rigol Dr. Philipp Heretsch Dr. Charles I. Grove Christopher R. H. Hale Dr. Abdelatif ElMarrouni 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(25):8559-8570
The total synthesis of Δ12‐prostaglandin J3 (Δ12‐PGJ3, 1 ), a reported leukemia stem cell ablator, through a number of strategies and tactics is described. The signature cross‐conjugated dienone structural motif of 1 was forged by an aldol reaction/dehydration sequence from key building blocks enone 13 and aldehyde 14 , whose lone stereocenters were generated by an asymmetric Tsuji–Trost reaction and an asymmetric Mukaiyama aldol reaction, respectively. During this program, a substituent‐governed regioselectivity pattern for the Rh‐catalyzed C?H functionalization of cyclopentenes and related olefins was discovered. The evolution of the synthesis of 1 from the original strategy to the final streamlined process proceeded through improvements in the construction of both fragments 13 and 14 , exploration of the chemistry of the hitherto underutilized chiral lactone synthon 57 , and a diastereoselective alkylation of a cyclopentenone intermediate. The described chemistry sets the stage for large‐scale production of Δ12‐PGJ3 and designed analogues for further biological and pharmacological studies. 相似文献
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996.
Dempe Stephan Dinh Nguyen Dutta Joydeep Pandit Tanushree 《Mathematical Programming》2021,188(1):227-253
Mathematical Programming - In this paper we discuss the simple bilevel programming problem (SBP) and its extension, the simple mathematical programming problem under equilibrium constraints... 相似文献
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We study the problem of inhomogeneous diophantine approximation under certain primality restrictions. 相似文献
1000.