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81.
Barbara Odell Stephen J. Hammond Richard Osborne Michael W. Goosey 《Journal of computer-aided molecular design》1996,10(2):89-99
Summary Proctolin (Arg-Tyr-Leu-Pro-Thr) was the first insect neuropeptide to be chemically characterised. It plays an essential role in insect neurophysiology and is involved in muscular contraction and neuromodulation. Elements of secondary structure in solution have been studied by comparing data obtained from NMR and molecular dynamics simulations. Different secondary structural requirements are associated with agonist and antagonist activities. A favoured conformation of proctolin has an inverse -turn, comprising an intramolecular hydrogen bond near the C-terminal end between Thr NH and Leu CO. Antagonists have a more compact structure resembling a paperclip loop, containing an intramolecular hydrogen bond between Tyr NH and Pro CO, possibly stabilised by a salt bridge between the N- and C-terminal groups. A cyclic analogue retains antagonist activity and resembles a -bulge loop, also comprising intramolecular hydrogen bonds between Tyr NH and Pro CO and Thr CO. These models may offer feasible starting points for designing novel compounds with proctolinergic activity. 相似文献
82.
Bogert D Burnstein R Fisk R Fuess S Morfin J Ohska T Stutte L Walker JK Bofill J Busza W Eldridge T Friedman JI Goodman MC Kendall HW Kostoulas IG Lyons T Magahiz R Mattison T Mukherjee A Osborne L Pitt R Rosenson L Sandacz A Tartaglia M Taylor FE Verdier R Whitaker S Yeh GP Abolins M Brock R Cohen A Ernwein J Owen D Slate J Weerts H 《Physical review letters》1985,55(19):1969-1972
83.
David A. Price Kim James Simon Osborne Gareth W. Harbottle 《Tetrahedron letters》2007,48(41):7371-7373
The highly regioselective fluorination of 1-hydroxyisoquinoline is described using Selectfluor™ (F-TEDA-BF4) under a variety of conditions. 相似文献
84.
Gareth W. Harbottle Neil Feeder Karl R. Gibson Mel Glossop Graham N. Maw William A. Million Florence F. Morel Simon Osborne Cedric Poinsard 《Tetrahedron letters》2007,48(24):4293-4296
The syntheses of 6-fluoropyrido[3,4-d]pyrimidin-4-ylamine derivatives is reported herein. Methods for generating C, N and O linked analogues under microwave irradiation are described. 相似文献
85.
Thomas Osborne und Isaak F. Harris 《Fresenius' Journal of Analytical Chemistry》1906,45(12):733-741
Ohne Zusammenfassung 相似文献
86.
Thomas L. Osborne und Isaak F. Harris 《Fresenius' Journal of Analytical Chemistry》1904,43(6-7):372-376
Ohne ZusammenfassungAus einem gütigst zugesandten Abdruck aus dem Journal of the American chemical Society25, No. 8, bearbeitet und übersetzt von Dr. Griessmayer. 相似文献
87.
Thomas B. Osborne und S. H. Clapp 《Fresenius' Journal of Analytical Chemistry》1910,49(3-4):146-152
Ohne Zusammenfassung 相似文献
88.
A method for the rapid determination of the oxidation rate of naturally occurring pyrite (FeS2) samples is presented. The progress of the oxidation reaction was followed by measurement of the concentration of total dissolved iron using flow injection analysis. Iron was determined using UV-vis detection after reaction with the colorimetric reagent 5-sulfosalicylic acid in the presence of ammonia. The calibration function was linear between 5 and 150 mg L−1, and the detection limit was 0.46 mg L−1. The relative standard deviation was typically less than 1% (n = 10) and the measurement frequency was 60/h. The method was used to quantify the oxidation rate of 10 ground and cleaned pyrite samples (53 μm < x < 106 μm) from various international locations that were subjected to accelerate oxidation in acidic hydrogen peroxide. Results of these experiments showed that there was almost an order of magnitude of difference in oxidation rates of the pyrite samples. 相似文献
89.
We establish a general scaling law for the entanglement of a large class of ground states and dynamically evolving states of quantum spin chains: we show that the geometric entropy of a distinguished block saturates, and hence follows an entanglement-boundary law. These results apply to any ground state of a gapped model resulting from dynamics generated by a local Hamiltonian, as well as, dually, to states that are generated via a sudden quench of an interaction as recently studied in the case of dynamics of quantum phase transitions. We achieve these results by exploiting ideas from quantum information theory and tools provided by Lieb-Robinson bounds. We also show that there exist noncritical fermionic systems and equivalent spin chains with rapidly decaying interactions violating this entanglement-boundary law. Implications for the classical simulatability are outlined. 相似文献
90.