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Maurice Dörr Sebastian Lips Prof. Dr. Carlos Alberto Martínez-Huitle Dr. Dieter Schollmeyer Prof. Dr. Robert Franke Prof. Dr. Siegfried R. Waldvogel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(33):7835-7838
We report an innovative, sustainable and straightforward protocol for the synthesis of N,N-diarylamides equipped with nonprotected hydroxyl groups by using electrosynthesis. The concept allows the application of various substrates furnishing diarylamides with yields up to 57 % within a single and direct electrolytic protocol. The method is thereby easy to conduct in an undivided cell with constant current conditions offering a versatile and short-cut alternative to conventional pathways. 相似文献
3.
Triggering the Directional Selectivity of a Ring‐Closure Reaction Leads to Pyridoazacarbazoles with Anticancer Properties 下载免费PDF全文
Tamara N. Steinhauer Daniel S. Längle Dr. Christopher Meier Dr. Ulrich Girreser Dr. Lars Stenzel Prof. Dr. Dieter Heber Prof. Dr. Bernd Clement 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(18):6668-6672
We herein describe a facile and versatile synthetic route to the tetracyclic system of 6‐substituted 5,6‐dihydro‐11H‐pyrido[3,2‐i]‐1‐azacarbazoles with promising anticancer properties. These derivatives are built up by an elegant one‐step base‐catalyzed synthetic procedure from commercially available building blocks. One additional step provides the corresponding skeleton hitherto unknown in the literature. The possibility to synthesize a large library of compounds with various substitution patterns utilizing this method underlines the importance of this synthetic procedure. 相似文献
4.
Brian R. Holder Colleen A. McNaney David Luchetti Eric Schaeffer Dieter M. Drexler 《Biomedical chromatography : BMC》2015,29(9):1375-1379
Acetyl‐l ‐carnitine (ALCAR) is a potential biomarker for the modulation of brain neurotransmitter activity, but is also present in cerebrospinal fluid (CSF). Recent studies have utilized hydrophilic interaction liquid chromatography–tandem mass spectrometry (HILIC‐MS/MS) based assays to detect and quantify ALCAR within biofluids such as urine, plasma and serum, using various sample pretreatment procedures. In order to address the need to quantify ALCAR in CSF on a high‐throughput scale, a new and simple HILIC‐MS/MS assay has been successfully developed and validated. For rapid analysis, CSF sample pretreatment was performed via ‘dilute and shoot’ directly onto an advanced HILIC column prior to MS/MS detection. This newly developed HILIC‐MS/MS assay shows good recoveries of ALCAR without the need for chemical derivatization and multistep sample extraction procedures. The employment of this assay is suitable for the high‐throughput bioanalysis and quantification of ALCAR within the CSF of various animal models and human clinical studies. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
5.
Lars J. Wesenberg Erika Diehl Till J. B. Zähringer Carolin Dörr Dr. Dieter Schollmeyer Dr. Akihiro Shimizu Prof. Dr. Jun-ichi Yoshida Prof. Dr. Ute A. Hellmich Prof. Dr. Siegfried R. Waldvogel 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(72):17574-17580
The efficient production of many medicinally or synthetically important starting materials suffers from wasteful or toxic precursors for the synthesis. In particular, the aromatic non-protected primary amine function represents a versatile synthetic precursor, but its synthesis typically requires toxic oxidizing agents and transition metal catalysts. The twofold electrochemical amination of activated benzene derivatives via Zincke intermediates provides an alternative sustainable strategy for the formation of new C−N bonds of high synthetic value. As a proof of concept, we use our approach to generate a benzoxazinone scaffold that gained attention as a starting structure against castrate-resistant prostate cancer. Further improvement of the structure led to significantly increased cancer cell line toxicity. Thus, exploiting environmentally benign electrooxidation, we present a new versatile and powerful method based on direct C−H activation that is applicable for example the production of medicinally relevant compounds. 相似文献
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NHC‐Catalyzed Asymmetric Synthesis of Functionalized Succinimides from Enals and α‐Ketoamides 下载免费PDF全文
Dr. Lei Wang Qijian Ni Marcus Blümel Tao Shu Prof. Dr. Gerhard Raabe Prof. Dr. Dieter Enders 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(22):8033-8037
The efficient asymmetric synthesis of highly substituted succinimides from α,β‐unsaturated aldehydes and α‐ketoamides via NHC‐catalyzed [3+2] cycloaddition has been developed. The new scalable protocol significantly expands the utility of NHC catalysis for the synthesis of heterocycles and provides easy access to assemble a wide range of succinimides from simple starting materials. 相似文献
8.
Asymmetric Synthesis of Fully Substituted Cyclopentane‐Oxindoles through an Organocatalytic Triple Michael Domino Reaction 下载免费PDF全文
Dr. Liang‐Hua Zou Arne R. Philipps Prof. Dr. Gerhard Raabe Prof. Dr. Dieter Enders 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(3):1004-1008
An efficient, highly stereoselective asymmetric synthesis of fully functionalized cyclopentanes bearing an oxindole moiety and several other functional groups in one pot has been developed. Key step is an organocatalytic triple Michael domino reaction forming three C?C bonds and six stereocenters, including a quaternary one. Starting from equimolar amounts of simple substrates, a high molecular complexity can be reached after a Wittig olefination in one pot. The new protocol can easily be scaled up to gram amounts. 相似文献
9.
Investigations of the Vicarious C‐Aminations of 5,7‐Dinitrobenzotriazole and 4,6‐Dinitrobenzotriazol‐3‐ium‐1‐oxide and Their Energetic Properties 下载免费PDF全文
Dieter Ehlers Prof. Dr. Thomas M. Klapötke Carolin Pflüger 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(45):16073-16082
This combined experimental and theoretical study details the vicarious nucleophilic substitution by amination of 5,7‐dinitrobenzotriazol ( 1 ) and 4,6‐dinitrobenzotriazole‐3‐ium‐1‐oxide ( 4 ) with trimethylhydrazinium iodide to afford the new corresponding one‐ and two‐time aminated compounds and investigations of its mechanism by EPR spectroscopy. The preferred position for the first amination is computed by spin density population and verified by X‐ray crystallography. The zwitterionic structure of 4 is investigated in solution by 1H NMR spectroscopy and in solid state by X‐ray diffraction. Furthermore, the crystal structure of 1 is presented. The energetic behavior of the aminated products as well as the starting materials 1 and 4 was investigated, regarding sensitivities and performance. 相似文献
10.
A Gallium‐Substituted Distibene and an Antimony‐Analogue Bicyclo[1.1.0]butane: Synthesis and Solid‐State Structures 下载免费PDF全文
M. Sc. Lars Tuscher Dr. Chelladurai Ganesamoorthy Dieter Bläser Dr. Christoph Wölper Prof. Dr. Stephan Schulz 《Angewandte Chemie (International ed. in English)》2015,54(36):10657-10661
RGa {R=HC[C(Me)N(2,6‐iPr2C6H3)]2} reacts with Sb(NMe2)3 with insertion into the Sb? N bond and elimination of RGa(NMe2)2 ( 2 ), yielding the Ga‐substituted distibene R(Me2N)GaSb?SbGa(NMe2)R ( 1 ). Thermolysis of 1 proceeded with elimination of RGa and 2 and subsequent formation of the bicyclo[1.1.0]butane analogue [R(Me2N)Ga]2Sb4 ( 3 ). 相似文献