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101.
We investigate the constraints imposed by current data on correlated mixtures of adiabatic and nonadiabatic primordial perturbations. We discover subtle flat directions in parameter space that tolerate large (approximately 60%) fractions of nonadiabatic fluctuations. In particular, larger values of the baryon density and a spectral tilt are allowed. The cancellations in the degenerate directions are explored and the role of priors is elucidated. 相似文献
102.
103.
Frank Würthner Carsten Tschierske Anke Krüger Klaus Ditrich Roland Pfau Henning Priepke Rolf Breinbauer Hans‐Achim Wagenknecht Gerald Drger Andreas Kirschning Norbert Sewald Uwe Beifuss Mathias O. Senge Thomas J. J. Müller Peter R. Schreiner Ruth Gschwind Bernd F. Straub Kilian Muiz Martin Oestreich Jrg Pietruszka Thomas Lindel Roderich Süßmuth Philippe Bisel Michael Müller Elmar Weinhold Andres Jschke Markus Albrecht Thorsten Bach Gtz Bucher Heinrich Heydt Jens Hartung 《Nachrichten aus der Chemie》2006,54(3):241-264
104.
We prove that, with rare exceptions, groups that are free products with amalgamation or HNN-extensions are of uniformly exponential
growth.
Translated fromMatematicheskie Zametki, Vol. 67, No. 6, pp. 811–815, June, 2000. 相似文献
105.
CO Extrusion in Homogeneous Gold Catalysis: Reactivity of Gold Acyl Species Generated through Water Addition to Gold Vinylidenes 下载免费PDF全文
M. Sc. Janina Bucher B. Sc. Tim Stößer Dr. Matthias Rudolph Dr. Frank Rominger Prof. Dr. A. Stephen K. Hashmi 《Angewandte Chemie (International ed. in English)》2015,54(5):1666-1670
Herein, we describe a new gold‐catalyzed decarbonylative indene synthesis. Synergistic σ,π‐activation of diyne substrates leads to gold vinylidene intermediates, which upon addition of water are transformed into gold acyl species, a type of organogold compound hitherto only scarcely reported. The latter are shown to undergo extrusion of CO, an elementary step completely unknown for homogeneous gold catalysis. By tuning the electronic and steric properties of the starting diyne systems, this new reactivity could be exploited for the synthesis of indene derivatives in high yields. 相似文献
106.
Tobias Michael Brütsch Pascal Bucher Prof. Karl‐Heinz Altmann 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(4):1292-1300
A new convergent total synthesis of the marine macrolide mandelalide A ( 1 ) has been developed that is based on macrocyclic ring closure by a Shiina‐type macrolactonization and the construction of the requisite precursor seco acid by a highly efficient Sonogashira cross‐coupling reaction between two fragments of comparable complexity. Key steps in the elaboration of the acid building block were the enantioselective, catalytic addition of a protected acetylene to crotonaldehyde and the construction of the tetrahydropyran unit that is embedded in the macrocycle by means of an acid‐catalyzed Prins reaction. The synthesis of the alcohol fragment features the formation of the trisubstituted tetrahydrofuran ring through an acetal cleavage/epoxide opening cascade reaction and a rarely used radical alkynylation of a primary alkyl iodide. Intriguingly, the dihydroxylation of a terminal double bond as part of the synthesis of this building block gave the same major product for both the α‐ and β‐AD‐mix reagents, albeit with moderate or low selectivity. Synthetic mandelalide A ( 1 ) was a potent proliferation inhibitor of A549, HT460, and H1299 human lung cancer cells in vitro, but not of SK‐N‐SH neuroblastoma cells. However, in no case did we observe complete cell kill even at the highest compound concentration tested (5 μm ). 相似文献
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109.
Geometriae Dedicata - Given a pants decomposition $$\mathcal {PC} = \{\sigma _1, \ldots , \sigma _{\xi }\}$$ on a hyperbolizable surface $$\Sigma $$ and a vector $${{\underline{c}}}= (c_1, \ldots ,... 相似文献
110.