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1.
Total synthesis of (±)‐glyflavanones and glychalcones was accomplished starting from the known 1‐(5‐hydroxy‐7‐methoxy‐2,2‐dimethyl‐2H‐chromen‐6‐yl)ethanone ( 6 ). A new approach to synthesis of flavanones, based on a high yielding N‐benzylcinchoninium salt catalyzed chromane ring forming enantio‐selective cyclization process, is described. Also, synthesis of (+)‐glyflavanone 1 , the natural enantiomer, was achieved through optical resolution of a key intermediate in racemic synthesis. 相似文献
2.
Efficient Synthesis of (−)‐Corynoline by Enantioselective Palladium‐Catalyzed α‐Arylation with Sterically Hindered Substrates
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Dr. Xiaofeng Rao Dr. Naikai Li Heng Bai Chaodi Dai Dr. Zheng Wang Prof. Dr. Wenjun Tang 《Angewandte Chemie (International ed. in English)》2018,57(38):12328-12332
Sterically hindered substrates can be employed in an enantioselective palladium‐catalyzed α‐arylation with the chiral monophosphorus ligand BI‐DIME. This process enabled an efficient synthesis of the antidepressant (S)‐nafenodone, a four‐step enantioselective synthesis of the Sceletium alkaloid (+)‐sceletium A‐4, a concise five‐step enantioselective synthesis of (?)‐corynoline, as well as a three‐step preparation of (?)‐DeN‐corynoline. 相似文献
3.
Protecting‐Group‐Free Enantioselective Synthesis of (−)‐Pallavicinin and (+)‐Neopallavicinin
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Bin Huang Lei Guo Prof. Yanxing Jia 《Angewandte Chemie (International ed. in English)》2015,54(46):13599-13603
The first enantioselective synthesis of (?)‐pallavicinin and (+)‐neopallavicinin has been achieved in 15 steps. The described synthesis avoids protecting‐group manipulations by synthesis designs predicated on highly chemo‐ and stereoselective transformations. Highlights of the synthesis include a palladium‐catalyzed enantioselective decarboxylative allylation to form the chiral all‐carbon quaternary stereocenter, a palladium‐catalyzed oxidative cyclization to assemble the [3.2.1]‐bicyclic moiety, and an unprecedented LiBHEt3‐induced fragmentation/protonation of an α‐hydroxy epoxide to form the α‐furan ketone with the desired configuration. 相似文献
4.
Dong‐Liang Huang Cdric Montigny Yong Zheng Veronica Beswick Ying Li Xiu‐Xiu Cao Thomas Barbot Christine Jaxel Jun Liang Min Xue Chang‐Lin Tian Nadge Jamin Ji‐Shen Zheng 《Angewandte Chemie (International ed. in English)》2020,59(13):5178-5184
The preparation of native S‐palmitoylated (S‐palm) membrane proteins is one of the unsolved challenges in chemical protein synthesis. Herein, we report the first chemical synthesis of S‐palm membrane proteins by removable‐backbone‐modification‐assisted Ser/Thr ligation (RBMGABA‐assisted STL). This method involves two critical steps: 1) synthesis of S‐palm peptides by a new γ‐aminobutyric acid based RBM (RBMGABA) strategy, and 2) ligation of the S‐palm RBM‐modified peptides to give the desired S‐palm product by the STL method. The utility of the RBMGABA‐assisted STL method was demonstrated by the synthesis of rabbit S‐palm sarcolipin (SLN) and S‐palm matrix‐2 (M2) ion channel. The synthesis of S‐palm membrane proteins highlights the importance of developing non‐NCL methods for chemical protein synthesis. 相似文献
5.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(6):1646-1650
With over 5000 members isolated to date, sesquiterpene lactones represent a prolific source of medicinal agents with several derivatives in human clinical trials. The guaianolides, a major subset of this group, have been intensely investigated from both medicinal and chemical‐synthesis perspectives for decades. To date, the myriad stereochemical permutations presented by this enormous family have precluded the synthesis of many unique members. Herein we report the total synthesis of the trans ‐fused 8,12‐guaianolide (+)‐mikanokryptin in 10 steps from (+)‐carvone. Notably, this synthesis is the first gram‐scale total synthesis of a guaianolide natural product. 相似文献
6.
《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2017,129(19):5311-5315
A concise, diversity‐oriented approach for the synthesis of naturally occurring 3‐amino‐ and 3‐nitro‐2,3,6‐trideoxypyranose derivatives and analogues thereof from simple sugars has been developed. In addition, we investigated the synthesis of various 3‐aminoglycosyl donors and their application in glycosylation reactions. These studies led to the successful synthesis of a tetrasaccharide containing four different 3‐aminosugar components using ortho ‐alkynylbenzoate donors. 相似文献
7.
Different approaches towards the synthesis of auranthine have been investigated. A completed synthesis of 3‐[2‐(4‐oxo‐3,4‐dihydro‐quinazolin‐2‐yl)‐3,4‐dihydro‐1H‐benzo[e][1,4]‐diazepine‐2,5‐dione, an auranthine precursor, which after dehydration with 50% propylphophonic acid anhydride solution in ethl acetate and DMA gave a C‐acetyl derivative of aurnathine. Additionally studies towards the synthesis of fused quinazolinones yielded the C‐acetylated pyrido[2,1‐b]quinazolinones or butyric acid derivatives. 相似文献
8.
Svyatoslav V. Polovkovych Andrii I. Karkhut Natalia G. Marintsova Volodymyr P. Novikov 《Heteroatom Chemistry》2010,21(6):392-396
A new approach to the synthesis of new heterocyclic compounds with triazine and 4‐thiazolidone fragments in one molecule is developed. The synthesis methods comprise [2+3]‐cyclocondensation reactions essential in the preparative synthesis of 4‐thiazolidone derivatives. The reactions of S,N‐nucleophiles with C2‐cyclization agents for the synthesis of a number of biologically active 2‐triazin‐4‐thiazolidones were investigated. The interaction of thiosemicarbazone of sym‐triazine with derivatives of α‐halogencarboxylic acids and maleic anhydride resulted in correspondent (2‐[2‐(4,6‐dichloro‐1,3,5‐triazin‐2‐yl)hydrazino]‐5‐(3,4,5‐ R‐p‐phenyl‐methyliden)‐1,3‐thiazol‐4‐ones obtained in the one‐step synthesis. © 2010 Wiley Periodicals, Inc. Heteroatom Chem 21:392–396, 2010; View this article online at wileyonlinelibrary.com . DOI 10.1002/hc.20631 相似文献
9.
《Journal of heterocyclic chemistry》2018,55(5):1183-1188
Coumarins represent an important group of natural products and a common part of various drugs and fluorescent dyestuffs. Herein, we present the synthesis of a coumarin that can serve as a key starting material in the design and synthesis of bioorthogonally applicable fluorogenic dyes. The synthesis of 7‐azido‐3‐formylcoumarin started from 7‐diallylaminocoumarin. This allyl protected aminocoumarin is otherwise hard to obtain by conventional methods but was conveniently accessed in good yields by a sequential, Wittig‐reaction–UV isomerization process. This sequential approach was studied in more details and applied for the synthesis of a series of substituted coumarins even in one‐pot. 相似文献
10.
On‐surface synthesis constitutes a rapidly growing field of research due to its promising application for creating stable molecular structures on surfaces. While self‐assembled structures rely on reversible interactions, on‐surface synthesis provides the potential for creating long‐term stable structures with well‐controlled properties, for example superior electron transport for future molecular electronic devices. On‐surface synthesis holds the promise for preparing insoluble compounds that cannot be produced in solution. Another highly exciting aspect of on‐surface synthesis is the chance to discover new reaction pathways due to the two‐dimensional confinement of the reaction educts. In this review, we discuss the current state‐of‐the‐art and classify the reactions that have been successfully performed so far. Special emphasis is put on electrically insulating surfaces, as these substrates pose particular challenges for on‐surface synthesis while at the same time bearing high potential for future use, for example, in molecular electronics. 相似文献
11.
Simon D. Kloß Wolfgang Schnick 《Angewandte Chemie (International ed. in English)》2019,58(24):7933-7944
Nitridophosphates and phosphorus nitrides are thoroughly investigated classes of nitrides. During thirty years of research, the methods for their synthesis evolved from the condensation of molecular precursors at moderate temperatures and ambient pressures to state‐of‐the‐art high‐pressure and high‐temperature processes. Landmark breakthroughs made in recent years led to a comprehension‐based proficiency in nitridophosphate synthesis that is illustrated by the large compositional and structural diversity of the nitridophosphates known today. Herein, we review the advances made in synthesis with regard to the prevalent problem of nitride synthesis: the susceptibility of nitride ions to oxidation. 相似文献
12.
13.
Lian‐Dong Guo Xiong‐Zhi Huang Shi‐Peng Luo Wen‐Sen Cao Yuan‐Ping Ruan Jian‐Liang Ye Pei‐Qiang Huang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2016,128(12):4132-4136
The first total synthesis of the alkaloid (−)‐haliclonin A is reported. The asymmetric synthesis relied on a novel organocatalytic asymmetric conjugate addition of nitromethane with 3‐alkenyl cyclohex‐2‐enone to set the stereochemistry of the all‐carbon quaternary stereogenic center. The synthesis also features a Pd‐promoted cyclization to form the 3‐azabicyclo[3,3,1]nonane core, a SmI2‐mediated intermolecular reductive coupling of enone with aldehyde to form the requisite secondary chiral alcohol, ring‐closing alkene and alkyne metathesis reactions to build the two aza‐macrocyclic ring systems, and an unprecedented direct transformation of enol into enone. 相似文献
14.
Dimethyl acetylenedicarboxylate (DMAD) is a very important and useful reagent for the preparation of dimethyl heterocyclic‐o‐dicarboxylates, which are key intermediates in the synthesis of fused pyridazine derivatives. The synthesis of thiopyranes by the Diels‐Alder reaction of dithiocarboxylate derivatives, synthesis of various cyclazines by [2 + 8] cycloaddition reactions, and synthesis of dimethyl pyrazolo[3,4‐b]pyridine‐5,6‐dicarboxylates and polycyclic heterocycles containing the 1,6‐naphthyridine ring system by the reaction of o‐aminonitrile compounds with DMAD are described here. 相似文献
15.
Eric E. Boros Istvan Kaldor Philip S. Turnbull 《Journal of heterocyclic chemistry》2011,48(3):733-736
2‐Methyl‐4‐(trifluoromethyl)‐1H‐indole‐5‐carbonitrile is a key intermediate in the synthesis of selective androgen receptor modulators discovered in these laboratories. A practical and convergent synthesis of the title compound starting from 4‐nitro‐3‐(trifluoromethyl)phenol and tert‐butyl acetoacetate was developed, including a telescoped procedure for synthesis (without isolation) and Nenitzescu reaction of 2‐trifluoromethyl‐1,4‐benzoquinone. Conversion of the known Nenitzescu indole product to a novel triflate intermediate followed by palladium‐catalyzed cyanation afforded a penultimate carbonitrile. Removal of the C‐3 tert‐butyl ester group on the indole through a decarboxylative pathway completed the synthesis of the title compound in six steps (27% overall yield) from 4‐nitro‐3‐(trifluoromethyl)phenol (five steps, 37% overall yield from tert‐butyl acetoacetate). J. Heterocyclic Chem., (2011). 相似文献
16.
M. Goldeck Prof. Dr. T. Tuschl Prof. Dr. G. Hartmann Dr. J. Ludwig 《Angewandte Chemie (International ed. in English)》2014,53(18):4694-4698
A novel solid‐phase synthesis and purification strategy for 5′‐triphosphate oligonucleotides by using lipophilic tagging of the triphosphate moiety is reported. This is based on triphosphate synthesis with 5′‐O‐cyclotriphosphate intermediates, whereby a lipophilic tag, such as decylamine, is introduced during the ring‐opening reaction to give a linear gamma‐phosphate‐tagged species. This method enables the highly efficient synthesis of 5′‐triphosphorylated RNA derivatives and their gamma‐phosphate‐substituted analogues and will especially facilitate the advancement of therapeutic approaches that make use of 5′‐triphosphate oligonucleotides as potent activators of the cytosolic immune sensor RIG‐I. 相似文献
17.
Scalable Synthesis of the Potent HIV Inhibitor BMS‐986001 by Non‐Enzymatic Dynamic Kinetic Asymmetric Transformation (DYKAT)
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Dr. Adrian Ortiz Dr. Tamas Benkovics Dr. Gregory L. Beutner Dr. Zhongping Shi Dr. Michael Bultman Dr. Jeffrey Nye Dr. Chris Sfouggatakis Dr. David R. Kronenthal 《Angewandte Chemie (International ed. in English)》2015,54(24):7185-7188
Described herein is the synthesis of BMS‐986001 by employing two novel organocatalytic transformations: 1) a highly selective pyranose to furanose ring tautomerization to access an advanced intermediate, and 2) an unprecedented small‐molecule‐mediated dynamic kinetic resolution to access a variety of enantiopure pyranones, one of which served as a versatile building block for the multigram, stereoselective, and chromatography‐free synthesis of BMS‐986001. The synthesis required five chemical transformations and resulted in a 44 % overall yield. 相似文献
18.
Synthesis of Triazole‐linked Homonucleoside Polymers through Topochemical Azide–Alkyne Cycloaddition
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Atchutarao Pathigoolla Prof. Dr. Kana M. Sureshan 《Angewandte Chemie (International ed. in English)》2014,53(36):9522-9525
There is a great deal of interest in developing stable modified nucleic acids for application in diverse fields. Phosphate‐modified DNA analogues, in which the phosphodiester group is replaced with a surrogate group, are attractive because of their high stability and resistance to nucleases. However, the scope of conventional solution or solid‐phase DNA synthesis is limited for making DNA analogues with unnatural linkages. Other limitations associated with conventional synthesis include difficulty in making larger polymers, poor yield, incomplete reaction, and difficult purification. To circumvent these problems, a single‐crystal‐to‐single‐crystal (SCSC) synthesis of a 1,5‐triazole‐linked polymeric ssDNA analogue from a modified nucleoside through topochemical azide–alkyne cycloaddition (TAAC) is reported. This is the first solvent‐free, catalyst‐free synthesis of a DNA analogue that proceeds in quantitative yield and does not require any purification. 相似文献
19.
Concise and Practical Asymmetric Synthesis of a Challenging Atropisomeric HIV Integrase Inhibitor
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Dr. Keith R. Fandrick Dr. Wenjie Li Dr. Yongda Zhang Dr. Wenjun Tang Joe Gao Dr. Sonia Rodriguez Nitinchandra D. Patel Dr. Diana C. Reeves Dr. Jiang‐Ping Wu Sanjit Sanyal Dr. Nina Gonnella Dr. Bo Qu Dr. Nizar Haddad Dr. Jon C. Lorenz Kanwar Sidhu June Wang Dr. Shengli Ma Dr. Nelu Grinberg Dr. Heewon Lee Dr. Youla Tsantrizos Dr. Marc‐André Poupart Dr. Carl A. Busacca Dr. Nathan K. Yee Dr. Bruce Z. Lu Dr. Chris H. Senanayake 《Angewandte Chemie (International ed. in English)》2015,54(24):7144-7148
A practical and efficient synthesis of a complex chiral atropisomeric HIV integrase inhibitor has been accomplished. The combination of a copper‐catalyzed acylation along with the implementation of the BI‐DIME ligands for a ligand‐controlled Suzuki cross‐coupling and an unprecedented bis(trifluoromethane)sulfonamide‐catalyzed tert‐butylation renders the synthesis of this complex molecule robust, safe, and economical. Furthermore, the overall synthesis was conducted in an asymmetric and diastereoselective fashion with respect to the imbedded atropisomer. 相似文献
20.
Ralf Wyrwa Manfred Friedrich Karin Adelhelm Ulrike Riese Ralf Thiericke Susanne Grabley 《无机化学与普通化学杂志》2000,626(9):1905-1908
A Novel Method to Identify Chemical Compounds of Combinatorial Libraries by the Use of Paramagnetic Tags An EPR method to identify non‐destructively chemical compounds bound to a single solid‐phase‐synthesis bead for combinatorial chemistry applications is discribed. During synthesis chemical inert paramagnetic substances can be attached in small amounts to a solid‐phase‐synthesis resin for tagging of organic compounds or even reaction steps. The identification of single members of a combinatorial library in short time and high sensitivity can be carried out by using an EPR‐spectrometer. 相似文献