Journal Sciences News
Analytica Chimica Acta
10 May 2018
Editorial Board
Publication date: 10 May 2018
Source:Tetrahedron, Volume 74, Issue 19

10 May 2018
Synthesis and biological activity of apratoxin derivatives
Publication date: 10 May 2018
Source:Tetrahedron, Volume 74, Issue 19 Author(s): Ettore J. Rastelli, Don M. Coltart This review covers the total asymmetric synthesis and biological evaluation of derivatives of the marine natural products known as the apratoxins.

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10 May 2018
ProteoFind: A script for finding proteins that are suitable for chemical synthesis
Publication date: 10 May 2018
Source:Tetrahedron, Volume 74, Issue 19 Author(s): Akira Shigenaga, Naoto Naruse, Akira Otaka ProteoFind is a computational script for finding proteins that are suitable for fragment ligation-based chemical synthesis. This paper describes the development and case studies of ProteoFind, which searches protein lists obtained from the UniProt website. Its application to visualize areas covered by several one-pot three-fragment ligation methods is also discussed. The results demonstrate that ProteoFind not only saves time when searching for synthetic target proteins, but also proposes many candidate proteins from among which biomedically interesting proteins could be found. It also enables clarification of the features of ligation methods by comparing the areas to which each ligation reaction is accessible.

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10 May 2018
Synthesis of
10 May 2018
Baylis-Hillman acetates in organic synthesis: A simple two-step strategy for oxindole-spiro-
10 May 2018
One pot synthesis of aminonaphthoquinone derivatives using Cu(II) immobilized on hyperbranched polyglycerol functionalized graphene oxide as a reusable catalyst under solvent-free conditions
Publication date: 10 May 2018
Source:Tetrahedron, Volume 74, Issue 19 Author(s): Hossein Naeimi, Maryam Farahnak Zarabi A new Cu(II) immobilized on hyperbranched polyglycerol (HPG) functionalized graphene oxide catalyst was prepared and characterized by FT-IR, TGA, FE-SEM, XRD, and ICP-OES techniques. This catalyst was used efficiently for the preparation of aminonaphthoquinones via one-pot three-component condensation reaction under solvent-free conditions. The catalyst could be easily recovered and reusable several times without a significant loss of activity, which make this method attractive and in a close agreement with green chemistry.

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10 May 2018
Iodine-mediated direct synthesis of multifunctional 2-aminobenzimidazoles from N-substituted o-diaminoarenes and isothiocyanates
Publication date: 10 May 2018
Source:Tetrahedron, Volume 74, Issue 19 Author(s): Zhen Wang, Qiongli Zhao, Jiao Hou, Wenquan Yu, Junbiao Chang Multifunctional 2-aminobenzimidazoles were directly synthesized through sequential addition of N-substituted o-diaminoarenes to isothiocyanates, formation of carbodiimides via I2-mediated oxidative desulfurization, and intramolecular cycloaddition. This efficient and eco-friendly synthetic process provides a facile access to diverse 2-aminobenzimidazole derivatives from readily accessible substrates under mild reaction conditions in a scalable fashion.

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10 May 2018
Rhodium(III)-catalyzed CH amination of 2-arylquinazolin-4(3H)-one with N-alkyl-O-benzoyl-hydroxylamines
Publication date: 10 May 2018
Source:Tetrahedron, Volume 74, Issue 19 Author(s): Yuanguang Zhang, Jiang Huang, Zhihong Deng, Xunchun Mao, Yiyuan Peng N-benzoate alkylamines were used as the aminating agents, a efficient Rh-catalyzed ortho CH amination of 2-arylquinazolin-4(3H)-one has been reported. The reactions exhibit high efficient and good functional group tolerance. Exclusive 2,6-bis-aminated product and good to excellent yields were obtained under mild reaction conditions.

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10 May 2018
Combining prolinamides with 2-pyrrolidinone: Novel organocatalysts for the asymmetric aldol reaction
Publication date: 10 May 2018
Source:Tetrahedron, Volume 74, Issue 19 Author(s): Ismini Vlasserou, Maria Sfetsa, Dimitrios-Triantafyllos Gerokonstantis, Christoforos G. Kokotos, Panagiota Moutevelis-Minakakis Peptides and especially prolinamides have been identified as excellent organocatalysts for the aldol reaction. The combination of prolinamides with derivatives bearing the 2-pyrrolidinone scaffold, deriving from pyroglutamic acid, led to the identification of novel organocatalysts for the intermolecular asymmetric aldol reaction. The new hybrids were tested both in organic and aqueous media. Among the compounds tested, 22 afforded the best results in petroleum ether, while 25 afforded the products in brine in high yields and selectivities. Then, various ketones and aldehydes were utilized and the products of the aldol reaction were obtained in high yields (up to 100%) with excellent diastereo- (up to 97:3 dr) and enantioselectivities (up to 99% ee).

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10 May 2018
Regioselective synthesis of 2,3-disubstituted 1-alkyl pyrrolo[2,3-b] quinoxalines through palladium-catalyzed Heck reaction of chalcones and evaluation of their anti-bacterial activities
Publication date: 10 May 2018
Source:Tetrahedron, Volume 74, Issue 19 Author(s): Tayebeh Besharati-Seidani, Ali Keivanloo, Babak Kaboudin, Akihiro Yoshida, Tsutomu Yokomatsu The regioselective synthesis of 1-alkyl-2-aryl-3-acyl pyrrolo[2,3-b]quinoxalines through palladium-catalyzed Heck coupling reaction/heteroannulation was reported. The reaction of N-alkyl/benzyl-3-chloroquinoxaline-2-amines with chalcones catalyzed by Pd(OAc)2 in the presence of KOtBu, as the base, in DMSO afforded the desired products in good-to-high yields. The MIC and MBC determinations revealed that these compounds could be used in the future research works for the development of antibiotics.

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10 May 2018
Transformations of S-substituted 5,7-dimethyl-4,5-diphenyl-3-thioxoperhydroimidazo[4,5-e]-1,2,4-triazin-2-ones under treatment of 1,2-benzoquinones and photochemical properties of reaction products
Publication date: 10 May 2018
Source:Tetrahedron, Volume 74, Issue 19 Author(s): Angelina N. Kravchenko, Sergei V. Vasilevskii, Galina A. Gazieva, Vladimir V. Baranov, Valery A. Barachevsky, Olga I. Kobeleva, Olga V. Venidiktova, Valentina A. Karnoukhova For the first time 5,7-di-tert-butyl-1,3-dimethyl-3a,9a-diphenyl-3,3a-dihydro-1H-benzo[5,6][1,4]dioxino[2,3-d]imidazol-2(9aH)-one 13 and complex 9 of 4,6-di-tert-butyl-3-nitrobenzene-1,2-diol with 1,3-dimethyl-4,5-diphenyl-1H-imidazol-2(3H)-one 10a were prepared by the reactions of 3-alkylthio-5,7-dimethyl-4a,7a-diphenyl-4a,5,7,7a-tetrahydro-1H-imidazo[4,5-e]-1,2,4-triazin-6(4H)-ones with 3,5-di-tert-butyl-1,2-benzoquinone 1 and 4,6-di-tert-butyl-3-nitro-1,2-benzoquinone 2, respectively. Photochemical transformations of compounds 9 and 10a as well as products of its photooxygenation involving singlet oxygen under UV irradiation: urea 16, isomeric 1,3-dimethyl-4,5-diphenylimidazolidin-2-ones 17 and 17
10 May 2018
Construction of indolenine-substituted spiro[pyrrolidine-2,3
10 May 2018
Total synthesis of viscumneoside III of Viscum coloratum
Publication date: 10 May 2018
Source:Tetrahedron, Volume 74, Issue 19 Author(s): Lei Zou, Zixue Zhang, Xiaowen Chen, Hua Chen, Yi Zhang, Jianqi Li, Yu Liu The first total synthesis of viscumneoside III, a promising anti-angina pectoris dihydroflavone O-glycoside isolated from Viscum coloratum was described here. Trichloroaceti-midate was employed as the apiofuranosyl donor to construct the key building block of homoeriodictyol-7-O-
10 May 2018
One-pot access to indolylchromeno[2,3-b]indoles via iodine-mediated Friedel-Crafts alkylation/oxidative coupling reaction of indoles and salicylaldehydes
Publication date: 10 May 2018
Source:Tetrahedron, Volume 74, Issue 19 Author(s): Guang-Qing Rong, Jian-Qiang Zhao, Xiao-Mei Zhang, Xiao-Ying Xu, Wei-Cheng Yuan, Ming-Qiang Zhou An I2-mediated Friedel-Crafts alkylation/oxidative coupling reaction of indoles and salicylaldehydes was developed. With the developed protocol, a series of indolylchromeno[2,3-b]indoles were obtained in good yields (up to 88%) under mild reaction conditions. Two possible reaction mechanisms were tentatively brought forward to account for the formation of the products in light of some control experiments.

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10 May 2018
Synthesis of 2-(9H-carbazol-1-yl)anilines from 2,3
10 May 2018
Graphical Abstract TOC cont'd
Publication date: 10 May 2018
Source:Tetrahedron, Volume 74, Issue 19

10 May 2018
Graphical abstract TOC
Publication date: 10 May 2018
Source:Tetrahedron, Volume 74, Issue 19

26 April 2018
Graphical abstract TOC
Publication date: 10 May 2018
Source:Tetrahedron, Volume 74, Issue 19

26 April 2018
Editorial Board
Publication date: 26 April 2018
Source:Tetrahedron, Volume 74, Issue 17

26 April 2018
TBHP/AIBN-Mediated Synthesis of 2-Amino-thioazoles from Active Methylene Ketones and Thiourea under Metal-free Conditions
Publication date: 26 April 2018
Source:Tetrahedron, Volume 74, Issue 17 Author(s): Jiyun Sun, Huaibin Ge, Xiaohua Zhen, Xuechan An, Guangtao Zhang, Daisy Zhang-Negrerie, Yunfei Du, Kang Zhao A new oxidative system of tert-butyl hydroperoxide (TBHP)/azodiisobutyronitrile (AIBN) has been used for the first time for a convenient, metal-free synthesis of substituted 2-aminothioazoles from active methylene ketone derivatives and thiourea. The reaction is postulated to proceed via an oxidative cyclization initiated by a radical process and followed by a condensation reaction.

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26 April 2018
Nematicidal quinone derivatives from three Rubia plants
Publication date: 26 April 2018
Source:Tetrahedron, Volume 74, Issue 17 Author(s): Si-Meng Zhao, Bin Kuang, Guang-Zhi Zeng, Zhe Wang, Jia Wang, Xiao-Qiang Chen, Ning-Hua Tan Five new quinone derivatives, rubiasins D-F (13), rubialatones A and B (4 and 5), have been isolated from the roots and rhizomes of three Rubia species, Rubia alata, R.wallichiana and R.schumanniana, together with 26 known quinones (631). Their structures have been elucidated on the basis of NMR, MS spectra and computational methods. The compounds have been evaluated for their toxicity to the saprophytic nematode Caenorhabditis elegans and the root-knot nematode Meloidogyne incognita. Compounds 1, 6 and 7 showed toxicity to C.elegans with the LC50 values at 8.50, 9.44 and 44.82
26 April 2018
Cu-catalyzed reduction of azaarenes and nitroaromatics with diboronic acid as reductant
Publication date: 26 April 2018
Source:Tetrahedron, Volume 74, Issue 17 Author(s): Danwei Pi, Haifeng Zhou, Yanmei Zhou, Qixing Liu, Renke He, Guanshuo Shen, Yasuhiro Uozumi A ligand-free copper-catalyzed reduction of azaarenes with diboronic acid as reductant in an aprotic solvent under mild conditions has been developed. Most interestingly, the nitroazaarenes could be reduced exclusively to give the corresponding amines without touching the azaarene moieties. Furthermore, the reductive amination of aromatic nitro compounds and aromatic aldehydes has also been realized. A series of hydrogenated azaarenes and secondary amines were obtained with good functional group tolerance.

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26 April 2018
Enantioselective phospha-Michael reaction of diethyl phosphonate with exocyclic
26 April 2018
Syntheses of cyclopentyl nucleoside (
26 April 2018
Rhodium-catalyzed reactions of 3-diazoindolin-2-imines with enamines and their extensions towards 5H-pyrazino[2,3-b]indoles
Publication date: 26 April 2018
Source:Tetrahedron, Volume 74, Issue 17 Author(s): Guorong Sheng, Shicong Ma, Songlin Bai, Jing Qian, Kai Huang, Bo Lang, Ping Lu, Yanguang Wang The rhodium-catalyzed reactions of 3-diazoindolin-2-imines with
26 April 2018
Diastereoselective approach to trans-5-hydroxy-6-substitutedethanone-2-piperidinones: Scalable syntheses of (+)-febrifugine and (+)-halofuginone
Publication date: 26 April 2018
Source:Tetrahedron, Volume 74, Issue 17 Author(s): Chen Wang, Yi-Wen Liu, Zhu Zhou, Chang-Mei Si, Xun Sun, Bang-Guo Wei An efficient diastereoselective approach to access trans-5-hydroxy-6-substitutedethanone-2-piperidinones skeleton has been developed through sequential addition-deprotection-cyclization process involving aldimine 6 with substituted acetones. The diastereoselectivity of substitution at C-6 position of 2-piperidinone was controlled by
26 April 2018
Conformational search and spectroscopic analysis of bis-
26 April 2018
Asymmetric ring-opening reaction of azabenzonorbornadienes with phenols promoted by palladium/(R,R)-DIOP complex
Publication date: 26 April 2018
Source:Tetrahedron, Volume 74, Issue 17 Author(s): Zhen Xiu He, Yongyun Zhou, Baiqiu Han, Xin Xu, Yun Li, Hongyu Qin, Ruifeng Fan, Ronibala Devi Laishram, Baomin Fan An efficient asymmetric ring opening reaction of azabenzonorbornadienes with various phenols using Palladium/(R,R)-DIOP complex has been demonstrated, the reaction afforded the corresponding products in excellent yields (8095%) with moderate enantioselectivities (5064% ees). The syn-configuration of the product was confirmed by the single X-ray crystallography.

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26 April 2018
A mechanistic investigation of an Iridium-catalyzed asymmetric hydrogenation of pyridinium salts
Publication date: 26 April 2018
Source:Tetrahedron, Volume 74, Issue 17 Author(s): Yuhua Huang, Shaodong Liu, Yizhou Liu, Yonggang Chen, Mark Weisel, R. Thomas Williamson, Ian W. Davies, Xumu Zhang NMR studies of the catalyst, deuteration experiments, mass spectrometry, and isolation and characterization of intermediates, allow us to propose an outer-sphere mechanism for the Iridium-catalyzed asymmetric hydrogenation of N-alkyl-2-arylpyridinium salts.

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26 April 2018
Graphical abstract TOC continued
Publication date: 26 April 2018
Source:Tetrahedron, Volume 74, Issue 17

26 April 2018
Graphical abstract TOC
Publication date: 26 April 2018
Source:Tetrahedron, Volume 74, Issue 17

19 April 2018
Graphical abstract TOC
Publication date: 26 April 2018
Source:Tetrahedron, Volume 74, Issue 17

19 April 2018
Editorial Board
Publication date: 19 April 2018
Source:Tetrahedron, Volume 74, Issue 16

19 April 2018
Asymmetric autocatalysis of pyrimidyl alkanol and related compounds. Self-replication, amplification of chirality and implication for the origin of biological enantioenriched chirality
Publication date: 19 April 2018
Source:Tetrahedron, Volume 74, Issue 16 Author(s): Kenso Soai, Tsuneomi Kawasaki, Arimasa Matsumoto We discovered asymmetric autocatalysis in the enantioselective addition of diisopropylzinc to pyrimidine-5-carbaldehyde, where the product 5-pyrimidyl alkanol acts as a highly efficient asymmetric autocatalyst to afford more of itself (Soai reaction). Asymmetric autocatalysis proceeded quantitatively (>99% yield), affording itself as a near enantiomerically pure (>99.5% ee) product. An extremely low enantiomeric excess (ca. 0.00005% ee) can automultiply during three rounds of consecutive asymmetric autocatalysis to >99.5% ee by asymmetric amplification. Circularly polarized light, and inorganic and organic crystals, act as the origin of chirality to trigger asymmetric autocatalysis. Asymmetric autocatalysis has enormous power to recognize and amplify the chirality of hydrogen, carbon, oxygen, and nitrogen isotopomers. Moreover, absolute asymmetric synthesis, i.e., the formation of enantioenriched compounds without the intervention of any chiral factor, is realized by asymmetric autocatalysis. By using designed molecules based on 5-pyrimidyl alkanol, the intramolecular asymmetric control, self-replication, and improvement of chiral multifunctionalized large molecules has been developed by applying asymmetric autocatalysis.

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19 April 2018
Synthesis of N,N
19 April 2018
Copper-facilitated Suzuki-Miyaura coupling for the preparation of 1,3-dioxolane-protected 5-arylthiophene-2-carboxaldehydes
Publication date: 19 April 2018
Source:Tetrahedron, Volume 74, Issue 16 Author(s): Tam
19 April 2018
Design and synthesis of new carbohydrate-lithocholic acid conjugates linked via 1,2,3-triazole rings
Publication date: 19 April 2018
Source:Tetrahedron, Volume 74, Issue 16 Author(s): Claudia I. Bautista-Hern
19 April 2018
A chiral pool approach for asymmetric syntheses of both antipodes of equol and sativan
Publication date: 19 April 2018
Source:Tetrahedron, Volume 74, Issue 16 Author(s): Chinni Yalamanchili, Amar G. Chittiboyina, Sateesh Chandra Kumar Rotte, John A. Katzenellenbogen, William G. Helferich, Ikhlas A. Khan For the first time, both antipodes of the isoflavans, equol and sativan were synthesized in >98% ee with good overall yields starting from readily available starting materials. The chiral isoflavan, (
19 April 2018
Aminothiazoles and aminothiadiazoles as nucleophiles in aminocarbonylation of iodobenzene derivatives
Publication date: 19 April 2018
Source:Tetrahedron, Volume 74, Issue 16 Author(s): M
19 April 2018
A dichotomy in the enantioselective oxidation of aryl benzyl sulfides: A combined experimental and computational work
Publication date: 19 April 2018
Source:Tetrahedron, Volume 74, Issue 16 Author(s): Maria Annunziata M. Capozzi, Andrea Bottoni, Matteo Calvaresi, Cosimo Cardellicchio Pentafluorobenzyl pentafluorophenyl sulfide is oxidised with moderate e.e. value and a low yield by the usually highly successful oxidation protocol based upon tert-butyl hydroperoxide (TBHP) in the presence of a titanium/hydrobenzoin complex. This disappointing result resisted until the present work, in which the switch of the oxidation agent (from TBHP to cumene hydroperoxide), suggested by our previous computations, yielded the enantiopure sulfoxide. This valuable chiral compound was obtained in good yields (76%) without resorting to a chromatographic separation. DFT computations uncovered that this favourable reactivity was originated by a stabilizing
19 April 2018
Direct synthesis of anthracenes from o-tolualdehydes and aryl iodides through Pd(II)-Catalyzed sp3 CH arylation and electrophilic aromatic cyclization
Publication date: 19 April 2018
Source:Tetrahedron, Volume 74, Issue 16 Author(s): Hyojin Park, Kwangho Yoo, Byunghyuck Jung, Min Kim The first direct synthesis of substituted anthracenes from o-tolualdehydes and aryl iodides via a Pd(II)-catalyzed CH arylation using an alcohol-bearing transient directing group and subsequent AgOTf-assisted electrophilic aromatic cyclization is described. New transient directing groups consisting of amino acids and amino alcohols enhanced the reactivity, and the CH arylation was complete in 12
19 April 2018
Cembranoids from Eunicea sp. enhance insulin-producing cells proliferation
Publication date: 19 April 2018
Source:Tetrahedron, Volume 74, Issue 16 Author(s): G. Porras, A.R. D
19 April 2018
Catalyst-free photocyclization for the synthesis of spiro-fused aromatic organic semiconductor based on SFX
Publication date: 19 April 2018
Source:Tetrahedron, Volume 74, Issue 16 Author(s): Ming-Li Sun, Feng Zhang, Yan Qian, Chang-Jin Ou, Bin Liu, Ling-Hai Xie, Ying Wei, Bao-Yi Ren, Wei Huang A green protocol with catalyst-free photo-induced cyclization for the synthesis of a spiro-fused organic semiconductor molecule based on spiro[fluorene-9,9
19 April 2018
Facile preparation of 3-substituted 2-quinazolinones via electrogenerated base
Publication date: 19 April 2018
Source:Tetrahedron, Volume 74, Issue 16 Author(s): Najwa Sbei, Belen Batanero, Fructuoso Barba, Beya Haouas, Mohamed Lamine Benkhoud, Isidoro Barba A new series of 3,4-disubstituted quinazolin-2-ones, with potential T-type calcium channel antagonist activity, and new 4-methylene-quinazolin-2-ones, promising catalysts as N-heterocyclic olefins, have been prepared in good yield by a simple reaction between 2-aminobenzophenone, or 2-aminoacetophenone, and cyanomethyl anion electrogenerated by acetonitrile reduction at a graphite electrode, followed by the addition of different organic isocyanates and subsequent heterocyclization.

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19 April 2018
Facile synthesis of perfluoroalkylated fluorenes via a one-pot two-step three-component process
Publication date: 19 April 2018
Source:Tetrahedron, Volume 74, Issue 16 Author(s): Zhenhua Sun, Qi Huang, Jing Han, Weimin He, Jie Chen, Yuchen Xu, Hongmei Deng, Min Shao, Hui Zhang, Weiguo Cao The efficient synthesis of perfluoroalkyl-substituted fluorenes directly from indenones, malononitrile and methyl perfluoroalk-2-ynoates via a one-pot two-step three-component cascade process is reported. Up to 12 examples of indenones with various substituents were converted into their corresponding functionalized fluorene derivatives in good to excellent yields.

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19 April 2018
Isa
19 April 2018
Proton transfer process in synthesis of 3-acetyl-4-(substituted ethylenyl)coumarins and chromeno[3,4-c]pyridines
Publication date: 19 April 2018
Source:Tetrahedron, Volume 74, Issue 16 Author(s): Abdolali Alizadeh, Reza Mohammadi, Fahimeh Bayat, Long-Guan Zhu The triphenylphosphine mediated reactions of electron-deficient carbon-carbon triple bonds with 3-acetylcoumarins in dichloromethane afford functionalized 3-acetyl-4-(substituted ethylenyl)coumarins. Also, triphenylphosphine-catalyzed three-component cascade annulation reactions of 3-acetylcoumarins, activated acetylenic compounds, and hydrazines or amines provide a straightforward access to 3,5-dihydro-2H-chromeno[3,4-c]pyridine-1,2-dicarboxylates. In these strategies, the main step to the target products is proton transfer process. All products were obtained in good to high yields.

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19 April 2018
Anionic N-heterocyclic carbenes by decarboxylation of sydnone-4-carboxylates
Publication date: 19 April 2018
Source:Tetrahedron, Volume 74, Issue 16 Author(s): Ana-Luiza L
19 April 2018
Streptopyrazinones A

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Publication date: 19 April 2018
Source:Tetrahedron, Volume 74, Issue 16


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