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91.
92.
7-Amidocephalosporins are converted to the 7-diacylaminocephalosporins, which are oxidised exclusively to the 7-diacylamino-1α-sulfoxides. These compounds with benzylamine produce the 7-amidocephem-1α-sulfoxides. 相似文献
93.
Large-scale evacuations are a recurring theme on news channels, whether in response to major natural or manmade disasters. The role of warning dissemination is a key part in the success of such large-scale evacuations and its inadequacy in certain cases has been a ‘primary contribution to deaths and injuries’ (Hayden et al., 2007). Along with technology-driven ‘official warning channels’ (e.g. sirens, mass media), the role of unofficial channel (e.g. neighbours, personal contacts, volunteer wardens) has proven to be significant in warning the public of the need to evacuate. Although post-evacuation studies identify the behaviours of evacuees as disseminators of the warning message, there has not been a detailed study that quantifies the effects of such behaviour on the warning message dissemination. This paper develops an Agent-Based Simulation (ABS) model of multiple agents (evacuee households) in a hypothetical community to investigate the impact of behaviour as an unofficial channel on the overall warning dissemination. Parameters studied include the percentage of people who warn their neighbours, the efficiency of different official warning channels, and delay time to warn neighbours. Even with a low proportion of people willing to warn their neighbour, the results showed considerable impact on the overall warning dissemination. 相似文献
94.
A tunable microwave-assisted protocol for the synthesis of two biologically relevant families of heterocycles has been designed. Via a simple switch of reaction conditions, the same starting materials can be engaged in either an improved synthesis of the dihydrotriazine scaffold or a novel, first-in-class MCR to render the challenging 5-aminoimidazole nucleus in a single step. An additional first-in-class MCR is also reported utilizing guanidines to afford 2,5-aminoimidazoles. 相似文献
95.
Michael B. Hursthouse Andrew L. Porte Leylacaron S. Shaw Robert A. Shaw 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2):213-220
Abstract X-ray crystallographic structure determinations on a number of chlorocyclophosphazenes are compared with 35Cl N.Q.R. spectroscopic studies of these compounds. Phase changes have been observed. 相似文献
96.
THE REACTIONS OF N3P3CL6 AND RELATED COMPOUNDS WITH DIFUNCTIONAL REAGENTS. COMPARISONS AND CONTRASTS
Abdulla H. Alkubaisi W. Francis Deutsch Michael B. Hursthouse Harold G. Parkes Leylacaron S. Shaw Robert A. Shaw 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2):229-237
Abstract The reactions of N3P3Cl6 with a variety of difunctional reagents are discussed. NMR spectroscopic and X-ray crystallographic investigations are presented. 相似文献
97.
Ezzidine Ibrahim Ibrahim Abd-ellah Leyla S. Shaw Ibrahim Alnaimi 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):109-114
Abstract The formation and subsequent fragmentation of spirocyclodiphosph(V)azanes (II-III) has been studied by mass spectrometry using the link-field scan technique and structural inferencies are drawn from these data. 31P nmr measurements for compound (III) are also described. 相似文献
98.
Ann M. Tickner G. Kris Huang Kerry Gombatz Robert J. Mills Vance Novack Kevin S. Webb 《合成通讯》2013,43(16):2497-2505
Two efficient syntheses of methyl 4-mercaptobenzoate are described, one utilizing the dianion of 4-bromothiophenol, the other a SNAr reaction starting with 4-fluorobenzonitrile. 相似文献
99.
Andrew S. Bell Joseph Bradley Jeremy R. Everett Michelle Knight Jens Loesel John Mathias David McLoughlin James Mills Robert E. Sharp Christine Williams Terence P. Wood 《Molecular diversity》2013,17(2):319-335
The screening files of many large companies, including Pfizer, have grown considerably due to internal chemistry efforts, company mergers and acquisitions, external contracted synthesis, or compound purchase schemes. In order to screen the targets of interest in a cost-effective fashion, we devised an easy-to-assemble, plate-based diversity subset (PBDS) that represents almost the entire computed chemical space of the screening file whilst comprising only a fraction of the plates in the collection. In order to create this file, we developed new design principles for the quality assessment of screening plates: the Rule of 40 (Ro40) and a plate selection process that insured excellent coverage of both library chemistry and legacy chemistry space. This paper describes the rationale, design, construction, and performance of the PBDS, that has evolved into the standard paradigm for singleton (one compound per well) high-throughput screening in Pfizer since its introduction in 2006. 相似文献
100.
M. Morgan H. M. D. R. Herath P. J. Cabot P. N. Shaw A. K. Hewavitharana 《Analytical and bioanalytical chemistry》2012,404(10):3111-3121
Dynorphin A 1–17 (DYN A) is an endogenous neuropeptide that is of interest due to its diverse roles in analgesia, inflammation and addiction. Upon release, DYN A is subject to metabolism by a range of enzymes and its biotransformation is dependent on the site and environment into which it is released. In this study, we investigated the biotransformation of DYN A in rat inflamed tissue at pH?7.4 and 5.5, in rat serum and in trypsin solution. DYN A-porcine was incubated at 37?°C in each matrix over a range of incubation periods. The resultant fragments were separated using a C4 column and detected by mass spectrometry using total ion current mode. Incubation of DYN A in trypsin solution and in rat serum resulted in 6 and 14 fragments, respectively. Incubation in inflamed rat paw tissue occasioned 21 fragments at pH?7.4 and 31 fragments at pH?5.5. Secondary breakdown of some larger primary fragments was also observed in this study. 相似文献