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51.
A palladium-catalyzed parallel synthesis of bis-hetero(aryl) ketones is described with two further synthetic steps allowing easy entry to 3,3-di(hetero)arylpropylamines. 相似文献
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Björn Wängler Carmen Beck Esther Schirrmacher Frank Rösch Michael Eisenhut 《Tetrahedron letters》2006,47(33):5985-5988
The synthesis of tris-allyl-DOTA starting from cyclen and its application in the preparation of DOTA-peptide conjugates is reported. Clinically important conjugates such as DOTA-Tyr3-octreotide (DOTA-TOC), DOTA-Tyr3-octreotate (DOTA-TATE) as well as a DOTA-RGD peptide were synthesized in high yields with Fmoc solid phase peptide synthesis. The final, extremely reliable de-allylation was achieved on solid phase by different methods identifying morpholine/Pd(0) as the most suitable one obtaining all DOTA peptide conjugates in high yields. All DOTA-peptides were purified by reversed phase HPLC and structural identity was proved using MALDI-TOF mass spectrometry. 相似文献
54.
Marina DellaGreca 《Tetrahedron》2006,62(12):2877-2882
Examination of the hydroalcoholic extract of the leaves of Aptenia cordifolia has afforded three cinnamic acid amides and two lignanamides. Structures were established on the basis of spectroscopic data, including 2D-NMR analyses. 相似文献
55.
K. C. Nicolaou Dionisios Vourloumis Tianhu Li Joaquin Pastor Nicolas Winssinger Yun He Sacha Ninkovic Francisco Sarabia Hans Vallberg Frank Roschangar N. Paul King M. Ray V. Finlay Pareskevi Giannakakou Pascal Verdier-Pinard Ernest Hamel 《Angewandte Chemie (International ed. in English)》1997,36(19):2097-2103
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Demetrio Pitea Laura Bonati Elena Collina Ugo Cosentino Marina Lasagni Giorgio Moro Roberto Todeschini 《Fresenius' Journal of Analytical Chemistry》1994,348(1-2):111-120
Summary The role of multivariate analysis methods in evaluating, rationalizing, and working out complex environmental problems is discussed. The discussion is organized in two sections; a literature analysis of the application of chemometric methods to PCDD/PCDF data interpretation and source correlation and a review of the role of chemometric methods in analysing the results obtained by the Authors studying PCDD/PCDF formation and destruction mechanisms in MSW combustion processes. 相似文献
59.
Marina Gorunescu Florin Gorunescu Augustin Prodan 《Journal of Applied Mathematics and Computing》2002,9(1):185-195
Previous research has shown that the flow of patients around departments of geriatric medicine and ex-patients in the community may be modelled by the application of a mixed-exponential distribution. In this paper we considered a five-compartment model using a continuous-time Markov process to describe the flow of patients. Using a M/Ph/c queuing model, we present a way of optimizing the number of beds in order to maintain an acceptable delay probability at a sufficiently low level. Finally, we constructed a Java computer simulation, using data from St George’s Hospital, London. 相似文献
60.
In this paper we outline a new particle-mesh method for rapidly rotating shallow water flows based on a set of regularized equations of motion. The time-stepping method uses an operator splitting of the equations into an Eulerian gravity wave part and a Lagrangian advection part. An essential ingredient is the advection of absolute vorticity by means of translated radial basis functions. We show that this implies exact conservation of enstrophy. The method is tested on two model problems based on the qualitative features of the solutions obtained (i.e., dispersion or smoothness of potential vorticity contours) as well as on the increase in mean divergence level. 相似文献