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141.
Diamino‐ and diazidofuranoses represent useful precursors, for example, for the synthesis of substituted nucleosides and metal complexes, respectively. Known procedures for their synthesis lack the availability of cheap starting materials, adequate yields, and the access to all possible diastereomeres. Therefore, 3,5‐diazido‐3,5‐dideoxy‐ and ‐2,3,5‐trideoxyfuranoses both with ribo‐ and xylo‐configuration were prepared using different approaches. 相似文献
142.
143.
Prof. Dr. Sjoerd Harder Dominik Naglav Dr. Christian Ruspic Prof. Dr. Claudia Wickleder Dr. Matthias Adlung Dr. Wilfried Hermes Dr. Matthias Eul Prof. Dr. Rainer Pöttgen Dr. Daniel B. Rego Prof. Dr. Frederic Poineau Prof. Dr. Kenneth R. Czerwinski Prof. Dr. Rolfe H. Herber Prof. Dr. Israel Nowik 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(37):12173-12173
144.
Etienne Brachet Prof. Jean‐Daniel Brion Dr. Mouad Alami Dr. Samir Messaoudi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(45):15276-15280
Unprotected thioglycosides were effective nucleophiles for Ni0‐catalyzed C? S bond‐forming reaction with functionalized (hetero)aryl, alkenyl, and alkynyl halides. The functional‐group tolerance on the electrophilic partner was typically high and the anomeric selectivities of the thioglycosides were high in all cases. The efficiency of this general procedure was well‐demonstrated by the synthesis of 4‐methyl‐7‐thioumbelliferyl‐β‐D ‐cellobioside (MUS‐CB). 相似文献
145.
146.
Meike Koenig Tadas Kasputis Daniel Schmidt Keith B. Rodenhausen Klaus-Jochen Eichhorn Angela K. Pannier Mathias Schubert Manfred Stamm Petra Uhlmann 《Analytical and bioanalytical chemistry》2014,406(28):7233-7242
A combined setup of quartz crystal microbalance and generalized ellipsometry can be used to comprehensively investigate complex functional coatings comprising stimuli-responsive polymer brushes and 3D nanostructures in a dynamic, noninvasive in situ measurement. While the quartz crystal microbalance detects the overall change in areal mass, for instance, during a swelling or adsorption process, the generalized ellipsometry data can be evaluated in terms of a layered model to distinguish between processes occurring within the intercolumnar space or on top of the anisotropic nanocolumns. Silicon films with anisotropic nanocolumnar morphology were prepared by the glancing angle deposition technique and further functionalized by grafting of poly-(acrylic acid) or poly-(N- isopropylacrylamide) chains. Investigations of the thermoresponsive swelling of the poly-(N-isopropylacrylamide) brush on the Si nanocolumns proved the successful preparation of a stimuli-responsive coating. Furthermore, the potential of these novel coatings in the field of biotechnology was explored by investigation of the adsorption of the model protein bovine serum albumin. Adsorption, retention, and desorption triggered by a change in the pH value is observed using poly-(acrylic acid) functionalized nanostructures, although generalized ellipsometry data revealed that this process occurs only on top of the nanostructures. Poly-(N-isopropylacrylamide) is found to render the nanostructures non-fouling properties. 相似文献
147.
148.
Daniel Vogler Maximilian Schöner Dr. Elisabeth Kaifer Prof. Dr. Dr. Hans-Jörg Himmel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2022,28(49):e202201389
In this work we report the first cycloaddition reactions between a diazido diborane(4) and terminal alkynes, providing unique access to bis-1,2,3-triazoles connected by a B−B bridge. The catalyst-free reactions are highly selective, yielding exclusively the thermodynamically disfavored bis-1,4-triazoles. The reactions are enabled by the high thermal stability of the diazido-diborane [B(hpp)(N3)]2 (hpp=1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-α]pyrimidinate). Due to the tetra-coordinate boron atoms in this reagent, the reactions are tolerant with respect to the introduction of Lewis-basic groups at the alkyne. The scope and limitations of the new reactions are discussed. 相似文献
149.
Journal of Solid State Electrochemistry - We report the electrochemical behavior of free-standing functionalized graphene sheet electrode in a potential window corresponding to that of high-voltage... 相似文献
150.
do Nascimento CJ Figueroa-Villar JD 《Journal of magnetic resonance (San Diego, Calif. : 1997)》2007,187(1):126-130
In this paper we carried out a comparison between all the possible selective versions of the basic heteronuclear correlation experiment, the FUCOUP sequence. We concluded that the best experiment is that one in which the selective pulse is given in the carbon dimension, which we called SHESSLOC (Selective HEteronuclear Simultaneous Short and LOng-range Correlations). The sensitivity of the sequence was improved with the introduction of pulsed field gradients. 相似文献