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841.
842.
Toward Naphthocyclinones: Doubly Connected Octaketide Dimers with a Bicyclo[3.2.1]octadienone Core by Thiolate‐Mediated Cyclization 下载免费PDF全文
Dr. Yoshio Ando Subaru Hori Takumi Fukazawa Prof. Dr. Ken Ohmori Prof. Dr. Keisuke Suzuki 《Angewandte Chemie (International ed. in English)》2015,54(33):9650-9653
A viable method is reported for the synthesis of the bicyclo[3.2.1]octadienone scaffold in naturally occurring octaketide dimers. The procedure employs a reductive cyclization reaction mediated by an unusual ethanedithiol monosodium salt. 相似文献
843.
844.
Yuki Takemoto Prof. Dr. Hiroto Yoshida Prof. Dr. Ken Takaki 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(46):14841-14844
Regio‐ and stereoselective installation of boryl and stannyl moieties into a carbon–carbon triple bond of various alkynes has been achieved based on a three‐component coupling reaction by using a diboron and a tin alkoxide with the aid of a copper(II) acetate–tricyclohexylphosphine complex, giving diverse vic‐borylstannylalkenes in a straightforward manner. Carbon–tin and carbon–boron bonds of the resulting borylstannylation product are successively transformed into carbon–carbon bonds by a Migita–Kosugi–Stille and a Suzuki–Miyaura coupling, leading to the formation of (Z)‐tamoxifen with anti‐breast cancer activity. 相似文献
845.
Identification of six new Alternaria sulfoconjugated metabolites by high‐resolution neutral loss filtering 下载免费PDF全文
846.
847.
848.
D. G. Drake 《Applied Scientific Research》1964,13(1):29-36
Summary The impulsive motion of a flat plate through a viscous incompressible fluid with time-dependent suction applied normally at the plate is considered. An approximate solution is obtained which describes the motion of the fluid during the initial stage of the motion of the plate, and also one which describes the motion at later stages when the suction velocity is large. The particular case when the suction velocity depends linearly on the time is considered in detail. 相似文献
849.
M. F. Horstemeyer Ken Gall K. W. Dolan A. Waters J. J. Haskins D. E. Perkins A. M. Gokhale M. D. Dighe 《Theoretical and Applied Fracture Mechanics》2003,39(1):23-45
Void nucleation, growth, and coalescence in A356 aluminum notch specimens was determined from a combination of experiments, finite element analysis, nondestructive analysis, and image analysis. Notch Bridgman tension experiments were performed on specimens to failure and then other specimens were tested to 90%, 95%, and 98% of the failure load. The specimens were evaluated with nondestructive X-ray tomography and optical image analysis. Finite element simulations of the notch tests were performed with an elastic–plastic internal state variable material model that incorporated the pertinent microstructures (silicon particle volume fraction and size distribution and porosity volume fraction and size distribution). Parametric finite element simulations were performed to give insight into various initial conditions and responses of the notch tensile bars. The various methods all corroborated the same damage progression. 相似文献
850.
In this paper, we give a complete criterion for a discrete faithful representation ρ: F n →PSL(2, ?) to be primitive stable. This will answer Minsky’s conjectures about geometric conditions on ?3/ρ(F n ) regarding the primitive stability of ρ. 相似文献