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13 June 2018
Editorial Board
Publication date: 13 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 24

13 June 2018
Recent advances in transition-metal-catalyzed asymmetric reactions of diazo compounds with electron-rich (hetero-) arenes
Publication date: 13 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 24 Author(s): Yi-Pan Li, Zi-Qi Li, Shou-Fei Zhu The transition-metal-catalyzed reaction of diazo compounds with arenes or heteroarenes is an efficient and straightforward approach to functionalize aromatic compounds. This digest summarizes recent progresses on transition-metal-catalyzed asymmetric reactions of diazo compounds with electron-rich (hetero-) arenes, including CH functionalization, cascade reaction, cyclopropanation, cycloaddition, Buchner reaction and intramolecular dearomatization.

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13 June 2018
Recent advances in the synthesis and functionalization of 1,2,5-oxadiazole 2-oxides
Publication date: 13 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 24 Author(s): Nina N. Makhova, Leonid L. Fershtat Among the variety of nitrogen heterocycles, the furoxan (1,2,5-oxadiazole 2-oxide) scaffold has attracted considerable attention owing to its ability to release NO under physiological conditions. Therefore, significant efforts of organic chemists have been directed toward the construction of new drug candidates containing the NO-donor furoxan subunit connected to a known pharmaceutical or a potential pharmacophore by CC/CN bonds or through an appropriate linker. This digest summarizes the recent information concerning both new synthetic approaches for the furoxan ring construction and various methods for the functionalized furoxan synthesis with particular focus on the last three years. Methods for the furoxan ring formation including cyclodimerization of nitrile oxides, nitrosation of unsaturated compounds, and acylation of dinitromethane sodium salt are reviewed. The functionalization of furoxan ring is represented by nucleophilic substitution of nitro and arylsulfonyl groups as well as by different condensations of cyano-, carbonyl- and carboxyfuroxan derivatives. Synthesis of hybrid structures combining NO-donor furoxan ring and some pharmacophoric moiety is also considered.

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13 June 2018
Highly efficient and stereoselective cycloaddition of nitrones to indolyl- and pyrrolylacrylates
Publication date: 13 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 24 Author(s): Viktor A. Dmitriev, Mariia M. Efremova, Alexander S. Novikov, Vladimir V. Zarubaev, Alexander V. Slita, Anastasia V. Galochkina, Galina L. Starova, Andrey V. Ivanov, Alexander P. Molchanov The reactions of various nitrones with indolyl- and pyrrolylacrylates proceeds regioselectively with high diastereoselectivity in the case of aldonitrones, and represents an effective method for obtaining new indolyl- and pyrrolyl-substituted isoxazolidine carboxylates stabilized by weak (CH
13 June 2018
Reaction of Zn(II) with a BINOL-amino-acid Schiff base: An unusual off-on-off fluorescence response
Publication date: 13 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 24 Author(s): Xinjing Wang, Dan Shi, Yimang Xu, Shanshan Yu, Feng Zhao, Yachen Wang, Lingling Hu, Jun Tian, Xiaoqi Yu, Lin Pu An amino-acid based Schiff base (S)-2 is prepared from the condensation of (S)-3,3
13 June 2018
Copper diisobutyl-t-butoxyaluminum hydride: A novel reagent for chemoselective reduction of tertiary amides over esters
Publication date: 13 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 24 Author(s): So Hee Im, Won Kyu Shin, Ashok Kumar Jaladi, Duk Keun An We demonstrate that copper diisobutyl-t-butoxyaluminum hydride, readily prepared from lithium diisobutyl-t-butoxyaluminum hydride and CuI, effectively and chemoselectively reduces tertiary amides over esters at ambient temperature, affording the corresponding aldehydes in excellent yields.

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13 June 2018
Copper oxide nanoparticle catalysed synthesis of imidazo[1,2-a]pyrimidine derivatives, their optical properties and selective fluorescent sensor towards zinc ion
Publication date: 13 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 24 Author(s): Manish Rawat, Diwan S. Rawat Synthesis of biologically active fused imidazo[1,2-a]pyrimidines were achieved via A3 coupling involving 2-aminobenzimidazole, aldehyde and terminal alkyne, followed by 6-endo-dig cyclization using copper oxide nanoparticles under solvent free condition. Further optical properties of imidazo[1,2-a]pyrimidines were studied which showed the effect of electron-donating and electron-withdrawing substitution on the fluorescence intensities of these compounds. Out of 20 compounds, 2,4-bis(4-methoxyphenyl)benzo[4,5]imidazo[1,2-a]pyrimidine can act as a fluorescent sensor for zinc ion with detection limit 4.74
13 June 2018
Facile construction of 4H-chromenes via Michael addition of phenols to benzylidene oxobutanoates and their successful conversion into pyranocoumarins
Publication date: 13 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 24 Author(s): Priyanka, Rajesh K. Sharma, Ray J. Butcher, Diksha Katiyar An efficient and simple approach for the synthesis of functionalized 4H-chromenes has been developed via acid catalyzed Michael addition of phenols to benzylidene oxobutanoates. Preliminary mechanistic studies were conducted, suggesting that intermediate chroman derivative is initially formed which on dehydration produces final 4H-chromene. The conversion of 4H-chromenes into linear and angular pyranocoumarins is also described. The structural arrangements between the pyran and coumarin rings have been established by X-ray crystallographic analysis and 2D NMR spectroscopy.

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13 June 2018
Nitro-Mannich reaction and intramolecular 1,3-dipolar cycloaddition route to acylpyrrolidinones: Synthesis of a tetramic acid and (+)-laccarin
Publication date: 13 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 24 Author(s): Ryo Katsuta, Hiroki Ichijo, Ginka Oouchi, Arata Yajima, Ken Ishigami, Tomoo Nukada An efficient synthetic pathway to acylpyrrolidinones via a nitro-Mannich reaction, followed by the intramolecular 1,3-dipolar cycloaddition of a nitrile oxide to an alkyne was developed. The syntheses of a leucine-derived tetramic acid and natural tetramide (+)-laccarin were achieved in five steps using aldehydes, 2-alkynamides and nitromethane as the carbon sources.

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13 June 2018
An expedient access to chromanols via an arginine-mediated cascade cyclisation in water
Publication date: 13 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 24 Author(s): Ajit Kumar Jha, Heena Inani, Srinivasan Easwar A mild and efficient protocol for the synthesis of chromanols has been elaborated via an arginine-mediated cascade cyclisation reaction between salicylaldehyde and methyl vinyl ketone in water. Various substituted salicylaldehydes were successfully used in the aqueous based reaction, affording the chromanol adducts in very good yields. Mechanistically, the reaction presumably proceeds via an oxa-Michael addition followed by an intramolecular aldol addition pathway; the lack of stereoselectivity in the formation of the chromanols alludes to a non-covalent interaction of the amino acid with the substrates as the most plausible interpretation for the activation.

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13 June 2018
PTAB mediated open air synthesis of sulfonamides, thiosulfonates and symmetrical disulfanes
Publication date: 13 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 24 Author(s): Debayan Sarkar, Manoj Kumar Ghosh, Nilendri Rout A facile methodology has been described which has successfully simplified the generation of sulfonamides, thiosulfonates and symmetric disulfanes. This trio of reactions occur in an open air metal free atmosphere and has also been scaled up to grams making it suitable for commercialization. The reactions also have been successfully carried out with asymmetric variants, thus contributing to the chiral pool. The user friendly trio enables easy generation of these versatile sulfur analogues and the reaction condition employed depict an economic outline.

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13 June 2018
Metal-free synthesis of 1,2,3-triazoles via tandem azidation, intramolecular [3+2]-cycloaddition and aromatization of ethyl acrylate derivatives
Publication date: 13 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 24 Author(s): B. Senthil Kumar, Sunita Gadakh, Arumugam Sudalai An efficient one-pot method for the synthesis of substituted 1,2,3-triazole derivatives in excellent yields as single regioisomer is reported. The key transformation involves an atom-efficient tandem azidation, intramolecular [3+2]-cycloaddition and aromatization of acrylate derivatives on treatment with NaN3 in DMF under mild conditions.

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13 June 2018
Silver(II) oxide-mediated synthesis of 2,4-diarylquinazolines
Publication date: 13 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 24 Author(s): Wing Cheung, Raymond J. Patch, Mark R. Player A single-pot procedure for the synthesis of 2,4-diarylquinazolines is described which involves a silver oxide-mediated CH activation/CN bond formation process. The generality of this method with respect to substituent effects is presented along with studies leading to process optimization. Mechanistic investigations provide support for the involvement of radical intermediates in the reaction process.

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13 June 2018
A simple and fast-response fluorescent probe for hypochlorite in living cells
Publication date: 13 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 24 Author(s): Ruixue Ji, Kun Qin, Aikun Liu, Yan Zhu, Yanqing Ge A novel fluorophore pyrido[1,2-a]benzimidazole was synthesized and used as a fluorescent probe for hypochlorite based on the oxidation of hydrazine to carboxyl group. The detection limit was measured to be as low as 7.0
13 June 2018
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Publication date: 13 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 24

13 June 2018
Graphical abstract TOC
Publication date: 13 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 24

6 June 2018
Graphical abstract TOC
Publication date: 13 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 24

6 June 2018
Editorial Board
Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23

6 June 2018
Supramolecular systems constructed by crown ether-based cryptands
Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23 Author(s): Xintong Ren, Jing Zhang, Ming Cheng, Qi Wang, Juli Jiang, Leyong Wang Cryptands, seen as a kind of crown ether derivatives, have attracted much attention because of their three dimensional spatial structures and additional binding sites. Moreover, by changing functional groups on the third arm, various stimuli-responsive hostguest systems were obtained, which have played key roles in the construction of functional supramolecular systems. The recent advances in supramolecular systems constructed by crown ether-based cryptands, and further applications, especially in supramolecular polymers are summarized in this digest paper.

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6 June 2018
Transition-metal catalyzed enantioselective hydrofunctionalization of alkynes
Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23 Author(s): Yin Zheng, Weiwei Zi A significant number of reactions regarding hydrofunctionalization of alkynes have appeared in the literature over the years. This digest focus on the transition-metal catalyzed enantioselective alkyne hydrofunctionalization reactions. Based on the reaction mechanism, these reactions described herein are classified into three types. Strategies, substrate scope, along with mechanisms are highlighting.

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6 June 2018
Bioorthogonal chemistry: Optimization and application updates during 20132017
Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23 Author(s): Li-Huai Qin, Wei Hu, Ya-Qiu Long Bioorthogonal chemical groups to tag naturally occurring biomolecules in their native setting is a powerful tool for studying and manipulating biological processes, whereby unique functional groups incorporated into target biomolecules can be detected in a second step by using selective partners. On the other hand, bioorthogonal cleavage reactions enables chemically controlled spatiotemporal activation of intracellular proteins and prodrugs. Considerable attention has been focused on the bioorthogonal reactions, not only optimizing the known bioorthogonal reagents to gain fast reaction kinetics, high stability of the reagents and the products, but also extending new applications as well as developing new types of bioorthogonal reactions.

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6 June 2018
Synthesis of luminescent 2,3-diphenylmaleimide-labelled peptide nucleic acid oligomers
Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23 Author(s): Prasanna Ramani, Silvia Cauteruccio, Emanuela Licandro, Clara Baldoli A lys-GTAGATCACT-lys peptide nucleic acid (PNA) decamer labelled with the luminescent 2,3-diphenyl maleimido (DPM) group on the
6 June 2018
A dual-response naphthofluorescein-based fluorescent probe for multiple-channel imaging of cysteine/homocysteine in living cells
Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23 Author(s): Xiuxiu Yue, Wenxiu Li, Wenqiang Chen, Liangliang Zhang, Guofang Li, Jiarong Sheng A naphthofluorescein-based fluorescent probe with two independent reaction sites (nitro-2,1,3-benzoxadiazole and acrylate moiety) was developed. Integrating these two reaction sites into a single molecule not only can guarantee the selective detection of Cys/Hcy in an elegant fashion, but also can enable Cys/Hcy detection in a multiple-channel responsive manner.

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6 June 2018
Copper catalyzed access to functionalized oxazoles from oximes via carbenoids
Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23 Author(s): Anugula Nagaraju, K. Sandeep, K.C. Kumara Swamy An operationally simple, economical and straightforward synthesis of diverse oxazoles from oximes possessing a vicinal carbonyl group has been achieved by treatment of the latter with terminal diazo compounds like ethyl/benzyl diazoacetate and diazoacetophenone (which act as carbenoids) in one pot. At least two reducible functional groups (two ester groups or cyano
6 June 2018
Remote radical halogenation of aminoquinolines with aqueous hydrogen halide (HX) and oxone
Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23 Author(s): Li Qiao, Xianting Cao, Kejie Chai, Jiabin Shen, Jun Xu, Pengfei Zhang Simple and halide-atom economical HX reagents (X
6 June 2018
Detection of enantiomers of chiral primary amines by 1H NMR analysis via enamine formation with an enantiopure
6 June 2018
Sterically crowded triarylphosphines bearing cyano groups
Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23 Author(s): Shigeru Sasaki Sterically crowded triarylphosphines bearing one, two, and three cyano groups at 4-positions of aromatic substituents, namely, (4-cyano-2,6-diisopropylphenyl)n(2,4,6-triisopropylphenyl)3nP (n
6 June 2018
Stereodivergent synthesis of novel chiral C2-symmetric bis-trifluoromethyl-2-oxazolidinones
Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23 Author(s): Travis Remarchuk, E.J. Corey A simplified effective synthetic process is described for the diastereoselective synthesis of the chiral C 2-symmetric CF3-ureas (R,R)-15 and (S,S)-15 from (S)-
6 June 2018
One-pot Sonogashira coupling, hydroamination of alkyne and intramolecular CH arylation reactions toward the synthesis of indole-fused benzosultams
Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23 Author(s): Sudarshan Debnath, Shovan Mondal A one-pot Sonogashira coupling, hydroamination of alkyne and CH arylation reactions for the synthesis of indole-fused benzosultams are described. This method allows access to a variety of indole-fused seven membered benzosultams in good to excellent yields. The free indolyl nitrogen containing indole-fused benzosultams are also prepared by this method. The structures of the synthesized compounds are confirmed by single crystal XRD studies.

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6 June 2018
The opposite effect of K+ and Na+ on the hydrolysis of linear and cyclic dipeptides
Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23 Author(s): Thomas D. Campbell, Clara A. Hart, Rio Febrian, Mark L. Cheneler, Paul J. Bracher Potassium and sodium are generally considered inert spectator ions for organic reactions. Here, we report rate constants for the acid-promoted hydrolysis of the seven dipeptides of glycine (G) and alanine (A) and an unexpected pattern in how these rates differ in the presence of K+ and Na+. The linear dipeptides hydrolyze 1218% percent slower in the presence of KCl versus an equal concentration of NaCl, while the cyclic dipeptides hydrolyze 513% faster in the presence of KCl (all P-values
6 June 2018
Strontium-mediated selective protonation of unsaturated linkage of aromatic hydrocarbons and these derivatives
Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23 Author(s): Satoshi D. Ohmura, Masaharu Ueno, Norikazu Miyoshi The selective protonation of aromatic hydrocarbons with at least two or more aromatic rings and aromatic compounds bearing unsaturated linkages can be achieved by metallic strontium metal with ammonium chloride and iodine, or ammonium iodide in tetrahydrofuran. The reaction system is ammonia-free in room temperature and the reaction proceeds high selectivity in moderate to good yields.

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6 June 2018
Regio- and diastereoselective synthesis of new functionalized indolo[2,3-b]indole-pyrimidine based on CN bond formation via a four-component reaction
Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23 Author(s): Shima Nasri, Fatemeh Rahimi, Maryam Karimi, Mohammad Bayat A facile and diastereoselective synthetic procedure has been designed for the preparation of new substituted indolo[2,3-b]indole (IDID) moiety at position-5 of the pyrimidine ring by a one-pot four-component reaction of dimedone, aniline and substituted derivatives, barbituric acid/thiobarbituric acid and isatin under mild conditions. This method proceeds rely on a CsbndN bond formation under catalyst-free conditions affording a range of skeletally diversity 5-indolo[3,2-b]indole-pyrimidine-based heterocycles. 5-Indolo[2,3-b]indol-pyrimidine-2,4,6-trione and 5-indolo[2,3-b]indol-2-thioxo-pyrimidine-4,6-dione were obtained in EtOH solvent in high yield, short reaction time and diastereoselectivity. The structural diversities of the synthesized compounds have been confirmed spectroscopically, by IR 1H- and 13C NMR, EI-MS spectra and elemental analyses which agree with the proposed structures.

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6 June 2018
Solvent-free mechanochemical Buchwald-Hartwig amination of aryl chlorides without inert gas protection
Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23 Author(s): Qiao-Ling Shao, Zhi-Jiang Jiang, Wei-Ke Su A solvent-free Buchwald-Hartwig amination had been developed under high-speed ball-milling conditions, which afforded the desired products with moderate to high yields. The addition of sodium sulfate was found to be crucial for improving both the performance and the reproducibility. Comparative solvent-free stirring experiments implicated the importance of mechanical interaction for the transformation, and the inert gas was proved to be unnecessary for this amination.

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6 June 2018
Combining spiro-fused cyclohexadienone tetrahydrofuran ring system with glycine: Asymmetric synthesis of a new class of
6 June 2018
Rh(III)-catalyzed [4
6 June 2018
Ring current and anisotropy effects on OH chemical shifts in resonance-assisted intramolecular H-bonds
Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23 Author(s): Poul Erik Hansen, Andreas Koch, Erich Kleinpeter Ring current effects on resonance-assisted and intramolecularly bridged hydrogen bond protons for 10-hydroxybenzo[h]quinoline 1 and a number of related compounds were calculated and the through-space NMR shieldings (TSNMRS) obtained hereby visualized as iso-chemical-shielding surfaces (ICSS) of various size and direction. These calculations revealed that this through-space effect is comparably large (up to 2
6 June 2018
An unprecedented 7-membered ring enamide cyclization through hypervalent iodine phenolic oxidation
Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23 Author(s): Florian Berthiol, Christian Philouze, Pierre Y. Chavant, Jean-Fran
6 June 2018
One-pot synthesis of phosphorodiamidothioates using N-heterocyclic phosphine (NHP)-thiourea
Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23 Author(s): Ngantu Le, Hai Huang, Jun Yong Kang N-heterocyclic phosphine (NHP)-thiourea-promoted thiophosphation of thiols has been developed for the synthesis of phosphorodiamidothioates under additive-, metal-free reaction conditions. This reaction takes place at room temperature and exhibits good functional group tolerance. The key to success is that the thiourea group can serve as an excellent leaving group, which is tethered with NHP moiety.

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6 June 2018
Highly efficient synthesis of aryl ketones by PEPPSI-palladium catalyzed acylative Suzuki coupling of amides with diarylborinic acids
Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23 Author(s): Chen Wang, Lingyun Huang, Fengze Wang, Gang Zou An improved acylative cross-coupling of various N-methyl-N-tosyl amides with diarylborinic acids for synthesis of aryl ketones is developed. In most cases, aryl ketones could be obtained in excellent yields by using 1
6 June 2018
Terminal C(sp3)H alkylation of internal alkenes via Ni/H-catalyzed isomerization
Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23 Author(s): Zhen-Yu Wang, Jia-Hao Wan, Gao-Yin Wang, Rui Wang, Ruo-Xing Jin, Quan Lan, Xi-Sheng Wang An efficient nickel-catalyzed reductive relay cross-coupling of internal alkenes with alkyl (or aryl) halides has been developed. This method has demonstrated broad substrate scope, mild reaction conditions and excellent terminal-selectivity. Moreover, this efficient strategy could be applied to the terminal-selective alkylation of isomeric mixtures of internal alkenes.

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6 June 2018
Corrigendum to: Oxidative reactions of tetrahydrobenzimidazole derivatives with N-sulfonyloxaziridines [Tetrahedron Lett. 48 (2007) 57715774]
Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23 Author(s): Sivappa Rasapalli, Panduka Koswatta, Carl J. Lovely

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6 June 2018
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Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23

6 June 2018
Graphical abstract TOC
Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23

30 May 2018
Graphical abstract TOC
Publication date: 6 June 2018
Source:Tetrahedron Letters, Volume 59, Issue 23

30 May 2018
Editorial Board
Publication date: 30 May 2018
Source:Tetrahedron Letters, Volume 59, Issue 22

30 May 2018
Photocatalytic alkoxy radical-mediated transformations
Publication date: 30 May 2018
Source:Tetrahedron Letters, Volume 59, Issue 22 Author(s): Jing-Jing Guo, Anhua Hu, Zhiwei Zuo Alkoxy radicals have been intensively studied as versatile synthetic intermediates with well-established reactivity and selectivity. Due to the difficulties associated with the generation of these transient and high-energy radicals, the utilization of the unique reactivity of alkoxy radicals in catalytic platforms has become a rather challenging task. Recent studies on the alkoxy radical-mediated transformations have benefited tremendously from advances in modern photoredox catalysis. In this digest, we aim to highlight reported transformations that utilize alkoxy radicals in a photocatalytic fashion, in particular, underline novel catalytic platforms which we anticipate will find broad application in the near future.

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30 May 2018
Pursuing effective Gram-negative antibiotics: The chemical synthesis of negamycin
Publication date: 30 May 2018
Source:Tetrahedron Letters, Volume 59, Issue 22 Author(s): Lili Zhu, Ran Hong In this Digest paper, various approaches toward chemical synthesis of negamycin, a natural dipeptide-like antibiotic, were summarized. The strategy and tactics in each individual synthesis were highlighted. Although the chemical structure of negamycin is relatively simple, the promising bioactivity against Gram-negative bacteria with a novel mechanism of action renders it as an intriguing lead compound for medicinal development.

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30 May 2018
Geminal bis(boron) compounds: Their preparation and synthetic applications
Publication date: 30 May 2018
Source:Tetrahedron Letters, Volume 59, Issue 22 Author(s): Chaoqiang Wu, Jianbo Wang Geminal bis(boron) compounds have recently emerged as valuable building blocks for the synthesis of molecules with structural diversity. They have advantages of unique stability, operational simplicity and can be engaged in several kinds of transformations. This review covers the synthetic methods of geminal bis(boron) compounds and their applications in organic synthesis.

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30 May 2018
A convenient one-pot approach to Paclitaxel (Taxol) side chain via 1,3-dipolar cycloaddition of carbonyl ylides and N-benzoylbenzyl imines
Publication date: 30 May 2018
Source:Tetrahedron Letters, Volume 59, Issue 22 Author(s): Jiajun Sheng, Huan Chang, Yu Qian, Mingliang Ma, Wenhao Hu An efficient cascade approach to

Copper(II) catalyzed aromatization of tetrahydrocarbazole: An unprecedented protocol and its utility towards the synthesis of carbazole alkaloids
Publication date: 30 May 2018
Source:Tetrahedron Letters, Volume 59, Issue 22 Author(s): Bhakti A. Dalvi, Pradeep D. Lokhande An efficient protocol for the aromatization of tetrahydrocarbazole is described by using catalytic copper(II) chloride dihydrate in DMSO. This newly established methodology has utilized towards the synthesis of naturally occurring carbazole alkaloids, namely 3-methylcarbazole, 3-formyl carbazole, glycozoline, glycozolicine and clauszoline-K. In addition, the protocol is generalized for the aromatization of N-substituted tetrahydrocarbazole, 1,2,3,4-tetrahydroquinoline, 1,2,3,4-tetrahydroisoquinoline and 1,2,3,4-tetrahydro
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