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排序方式: 共有827条查询结果,搜索用时 156 毫秒
821.
Kim Anh Nguyen Emilie Lesur Maxime Ribéraud Antoine Sallustrau Davide Audisio Frédéric Taran 《Helvetica chimica acta》2023,106(3):e202200187
The synthesis of four clickable sydnone-heptamethine cyanine derivatives is described in this article. The synthetic route is based on a palladium-cross coupling reactions of sydnone boronates affording the desired sydnone-cyanine conjugates in only five steps. These compounds were shown to react smoothly with cyclooctynes to form the corresponding pyrazoles clicked products quantitatively at room temperature and with rate constants up to 18 m −1 ⋅ s−1, affording interesting new tools for biorthogonal fluorescent labelling of (bio)molecules. Fluorescence properties of both sydnone- and pyrazole-cyanines are described, as well. 相似文献
822.
Alexandre Labiche Augustin Malandain Maxime Molins Dr. Frédéric Taran Dr. Davide Audisio 《Angewandte Chemie (International ed. in English)》2023,62(36):e202303535
In contrast to stable and natural abundant carbon-12, the synthesis of organic molecules with carbon (radio)isotopes must be conceived and optimized in order to navigate through the hurdles of radiochemical requirements, such as high costs of the starting materials, harsh conditions and radioactive waste generation. In addition, it must initiate from the small cohort of available C-labeled building blocks. For long time, multi-step approaches have represented the sole available patterns. On the other side, the development of chemical reactions based on the reversible cleavage of C−C bonds might offer new opportunities and reshape retrosynthetic analysis in radiosynthesis. This review aims to provide a short survey on the recently emerged carbon isotope exchange technologies that provide effective opportunity for late-stage labeling. At present, such strategies have relied on the use of primary and easily accessible radiolabeled C1-building blocks, such as carbon dioxide, carbon monoxide and cyanides, while the activation principles have been based on thermal, photocatalytic, metal-catalyzed and biocatalytic processes. 相似文献
823.
ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option. 相似文献
824.
825.
Dr. Kévin Renault Romain Horion Xavier Maes Maha Rzeigui Dr. Yoann Joyard Dr. Nicolas Maindron Dr. Vincent Tadino Prof. Stéphane Vincent 《European journal of organic chemistry》2023,26(26):e202300307
2-Nitroimidazole based PET tracers are widely used for non-invasive hypoxic tumor diagnosis. In this context, we report here a general method based on a central Mitsunobu reaction to easily access 2-nitroimidazole precursors. Optimization of fluorination conditions is described and successfully applied to the radiofluorination of the 2-nitroimidazole precursors. Moreover, the radiosynthesis of a new potential hypoxia PET tracer is also described. Finally, this article presents a SFC analytical method allowing both an easy monitoring of the fluorination reactions and the measurement of partition coefficients (logP). 相似文献
826.
827.
Maxime Robin Stephane Mialhe Valerie Pique Robert Faure Jean‐Pierre Galy 《ChemInform》2002,33(38):153-153