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C. G. Overberger 《Journal of polymer science. Part A, Polymer chemistry》1975,13(10):2189-2190
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J. R. 《Nachrichten aus der Chemie》1979,27(11):693-693
“As mentioned below, I had rough times and frustating moments during my first year at Purdue. However, nothing has been more frustating than the fact that the Nobel Committee has kept mistreating H. C. Brown. While there can be chemists who are worthy of all prizes except Nobel Prize, H. C. Brown is definitely not one of them.” 相似文献
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C45- and C50-Carotenoids. Synthesis of an Optically Active Cyclic C20-Building Block and of (2R,2′S)-3′,4′-Didehydro-1′,2′-dihydro-2-(4-hydroxy-3-methylbut-2-enyl)-2′-(3-methylbut-2-enyl)-β,ψ-caroten-1′-ol (= C. p. 473) The synthesis of the optically active C20-building block (R)- 16 and of the optically active C50-carotenoid C.p. 473 ( 1 ) starting from (?)-β-pinene is reported. 相似文献
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Two new triterpenoid saponins, ilemaminosides A and B (1 and 2) along with six known saponins (3-8) were isolated from 70% ethanolic extract of the leaves of Ilex mamillata C.Y. Wu ex C.J. Tseng. The new saponins were characterised as 3-O-α-L-arabinopyranosyl-ilexgenin B (1) and 3-O-β-D-glucopyranosyl-(1?→?3)-α-L-arabinopyranosyl-ilexgenin B (2). The structures of compounds 1 and 2 were elucidated on the basis of the chemical and spectroscopic methods, and the structures of known compounds were identified by comparison of their spectroscopic data with those reported in the literature. The compounds showed inhibitory activities in anti-inflammatory assay in?vitro with IC(50) values in the range 25.37-38.33?μg?mL(-1). 相似文献
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A numerical simulation was done to check the possibility of using planar C/C/C multilayers with density contrast 0.2 and 0.7 g/cm3 as an X-ray waveguide. After an optimization procedure, suitable waveguide layer thicknesses were found which provide a high degree of resonant standing wave field intensity enhancement in the core layer at incident beam energy of 13 keV. The obtained results were compared with those of the Mo/Be/Mo waveguide, whose high waveguiding capability at the same energy value was reported in the 1990s. The comparison shows that standing wave field intensity resonant enhancement provided by C/C/C planar multilayers is very high and, consequently, a guided beam can be well detected. 相似文献
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C45- and C50-Carotenoids. Synthesis of Optically Active Acyclic C15-End Groups The optically active C15-end groups (S)- 12 , (S)- 13 and (R)- 14 were prepared from the C12-synthon (S)- 11 in good chemical and optical yield. These C15-end groups are suitable compounds for the synthesis of optically active C45- and C50-carotenoids. 相似文献
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《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2009,121(5):859-859
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