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141.
142.
Longley NP Bode CR Border PM Courant H DeMuth DM Gray RN Johns K Kasahara SM Lowe MJ Marshak ML Miller WH Mualem L Peterson EA Roback DM Ruddick K Schmid DJ Schub MH Shupe MA Vassiliev V Villaume G Werkema SJ Ayres DS Fields TH Gallagher HM Goodman MC Lopez FV May EN Price LE Seidlein RV Thron JL Trost H Uretsky JL Allison WW Barr GD Brooks CB Cobb JH Giller GL Stassinakis A Thomson MA West N Wielgosz U Alner GJ Cockerill DJ Cotton RJ Garcia-Garcia C Litchfield PJ Pearce GF Ewen B Kafka T 《Physical review D: Particles and fields》1995,52(5):2760-2765
143.
Bertelli M El-Bastawissy E Knaggs MH Barrett MP Hanau S Gilbert IH 《Journal of computer-aided molecular design》2001,15(5):465-475
A number of triphenylmethane derivatives have been screened against 6-phosphogluconate dehydrogenase from Trypanosoma brucei and sheep liver. Some of these compounds show good inhibition of the enzymes and also selectivity towards the parasite enzyme. Modelling was undertaken to dock the compounds into the active sites of both enzymes. Using a combination of DOCK 3.5 and FLEXIDOCK a correlation was obtained between docking score and both activity for the enzymes and selectivity. Visualisation of the docked structures of the inhibitors in the active sites of the enzymes yielded a possible explanation of the selectivity for the parasite enzyme. 相似文献
144.
Yardley JE Todd R Nicholson DJ Barrett J Kell DB Davey CL 《Bioelectrochemistry (Amsterdam, Netherlands)》2000,51(1):53-65
The deconvolution of biological dielectric spectra can be difficult enough with artefact-free spectra but is more problematic when machine baseline artefacts and electrode polarisation are present as well. In addition, these two sources of anomalies can be responsible for significant interference with dielectric biomass measurements made using one- or two-spot frequencies. The aim of this paper is to develop mathematical models of baseline artefacts and electrode polarisation which can be used to remove these anomalies from dielectric spectra in a way that can be easily implemented on-line and in real-time on the Biomass Monitor (BM). We show that both artefacts can be successfully removed in solutions of organic and inorganic ions; in animal cell and microbial culture media; and in yeast suspensions of varying biomass. The high quality of the compensations achieved were independent of whether gold and platinum electrodes were used; the electrode geometry; electrode fouling; current density; the type of BM; and of whether electrolytic cleaning pulses had been applied. In addition, the calibration experiments required could be done off-line using a simple aqueous KCl dilution series with the calibration constants being automatically calculated by a computer without the need for user intervention. The calibration values remained valid for a minimum of 3 months for the baseline model and indefinitely for the electrode polarisation one. Importantly, application of baseline correction prior to polarisation correction allowed the latter's application to the whole conductance range of the BM. These techniques are therefore exceptionally convenient to use under practical conditions. 相似文献
145.
Mitsunobu reaction of an alcohol ROH with a carboxylic acid, phthalimide, or N-hydroxyphthalimide (NuH) using DNAD (4) and (diphenylphosphino)polystyrene (11) gave the products RNu. Ring-opening metathetic polymerization of the side product DNADH(2) (3) using Cl(2)(Cy(3)P)(2)Ru=CHPh (13) and filtration, to remove poly(DNADH(2)), (diphenylphosphino)polystyrene 11, its oxide, and its adduct with excess DNAD, gave RNu (43-100%, 86-96% purity) without recourse to chromatography. 相似文献
146.
G. Valensi R. H. Crist F. B. Brown L. Williams A. H. Wilson Busby L. S. Echols Jr M. A. Smith F. L. Hayes C. H. Townes H. K. Alber A. Knoll J. Schukal E. P. Barrett W. E. Holbrook J. S. Blair A. V. Grosse W. N. Ipatjew H. J. Hall G. B. Bachman A. Klemenc A. Stock H. Kühne A. Bellmann J. Haller W. H. Albrecht K. P. GRohr H. Hillemann H. A. Wilhelm W. MacNevin H. S. Clark K. R. More R. F. Humphreys W. W. Watson P. A. Anderson G. Atchison D. O. Holland H. Sieben T. Langer 《Analytical and bioanalytical chemistry》1944,127(1):197-202
147.
Matthew J. Fuchter Sven M. Baum Efstathia G. Sakellariou Todd Miller Andrew J.P. White Anthony G.M. Barrett Brian M. Hoffman 《Tetrahedron》2005,61(25):6115-6130
The syntheses of a variety of substituted diaminomaleonitriles, with variable nitrogen substituents, were undertaken. Linstead macrocyclization of the resulting diaminomaleonitriles gave access to a wide range of functionalized porphyrazine-octaamines and hexamines and norphthalocyaninediamines. Conversion of these macrocycles into metallic derivatives and studies of their electronic absorption, solubility and electrochemistry are described. These flexible tetraazaporphyrins show potential in a range of applications including biomedical agents, novel charge-transfer complexes, chemical sensors, novel electronic materials and non-linear optics. 相似文献
148.
149.
Carboxylic acids were protected as their corresponding 3-butenyl esters. Deprotection was carried out via ozonolysis and β-elimination of the resultant 3-acyloxypropanal. 相似文献
150.
Panayiotis A. Procopiou Tim N. Barrett Royston C.B. Copley Christopher J. Tame 《Tetrahedron: Asymmetry》2017,28(10):1384-1393
The absolute configuration of two novel αvβ6 integrin inhibitors was established via degradation to the corresponding C3-aryl substituted butyrolactone. The configuration of the resulting lactones was established by asymmetric synthesis using 1,4-addition of arylboronic acids to butenolide, catalysed by bis(norbornadiene)rhodium (I) tetrafluoroborate in the presence of (R)-BINAP, and confirmed by X-ray crystallography. Studies on arylboronic acid conjugate additions to acyclic crotonate esters bearing a γ-oxygen substituent are also reported. Three Rh catalysts were investigated and the one giving the highest enantioselectivity was bis(norbornadiene)rhodium (I) tetrafluoroborate. 相似文献