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Thomas J. Greshock Keith P. Moore Ray T. McClain Ana Bellomo Cheol K. Chung Spencer D. Dreher Peter S. Kutchukian Zhengwei Peng Ian W. Davies Petr Vachal Mario Ellwart Sophia M. Manolikakes Prof. Dr. Paul Knochel Philippe G. Nantermet 《Angewandte Chemie (International ed. in English)》2016,55(44):13714-13718
The reactivity of a representative set of 17 organozinc pivalates with 18 polyfunctional druglike electrophiles (informers) in Negishi cross‐coupling reactions was evaluated by high‐throughput experimentation protocols. The high‐fidelity scaleup of successful reactions in parallel enabled the isolation of sufficient material for biological testing, thus demonstrating the high value of these new solid zinc reagents in a drug‐discovery setting and potentially for many other applications in chemistry. Principal component analysis (PCA) clearly defined the independent roles of the zincates and the informers toward druggable‐space coverage. 相似文献
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Jung-Suk Oh Phillip E. Warwick Ian W. Croudace Sang-Han Lee 《Journal of Radioanalytical and Nuclear Chemistry》2014,299(1):187-191
Traditionally in bioassay monitoring, 3H determinations in urine have been performed using either direct counting (with or without sample decolourisation) or distillation whilst 14C has been determined on separate sub-samples following chemical isolation of the carbon from samples. Although these techniques are relatively straightforward they do not permit simultaneous determination of 3H/14C. For 3H, direct counting can be significantly affected by variations in sample composition/colour resulting in varying degrees of sample quench, does not distinguish between aqueous/organically-bound 3H and is limited to small sample sizes. This study describes the use of purpose built multi-tube combustion furnace for the simultaneous extraction and determination of 3H and 14C. The technique is insensitive to sample composition and can be adapted to measure Tritiated water (HTO) and organically bound tritium separately. The development of a multi-tube system with integrated cool-down facility permits rapid throughput of high sample numbers and has been proven effective in decommissioning waste characterisation. In addition, the furnace-based technique is capable of processing larger sample sizes, increasing analytical sensitivity and accuracy of dose assessment. 相似文献
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Ian Hamerton Lisa T. McNamara Brendan J. Howlin Paul A. Smith Paul Cross Steven Ward 《Journal of polymer science. Part A, Polymer chemistry》2014,52(14):2068-2081
Three commercial bis‐benzoxazine monomers based on the aniline derivatives of bisphenol A (BA‐a), bisphenol F (BF‐a), and 3,3′‐thiodiphenol (BT‐a) are examined using a variety of spectroscopic, chromatographic, and thermomechanical techniques. The kinetics of the polymerization of BA‐a were found to be well described using an autocatalytic model for which values of n = 1.39 and m = 2.49 were obtained for the early and later stages of reaction respectively (activation energy = 81–88 kJ/mol.). Following recrystallization the same monomer yielded values of n = 1.80, m = 0.92, and Ea = 94–97 kJ/mol. BF‐a and BT‐a were also found to be well described using an autocatalytic model for which values of n = m = 2.11 (BF‐a) and n = 2.10, m = 1.47 (BT‐a) were obtained for the early and later stages of reaction (activation energy = 80–84 kJ/mol. for BF‐a and 88–95 kJ/mol. for BT‐a). The kinetic data are compared with parallel studies involving chemically initiated benzoxazine monomers. Molecular simulation is used to examine the rotational freedom of the central bridging units and this is related to the degree of conversion achieved. © 2014 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014 , 52, 2068–2081 相似文献