supplementary-content

A new efficient synthesis of oseltamivir phosphate (Tamiflu) from (-)-shikimic acid

January 26, 2012

Publication year: 2012 Source: Tetrahedron Letters, Available online 25 January 2012 Hee-Kwon Kim, Kyoung-Joo Jenny Park New synthesis of oseltamivir phosphate was accomplished in 9 steps with 27% overall yield from a readily available (-)-shikimic acid. Selective ring opening reaction of ketal and azide Mitsunobu reaction for facile replacement of a hydroxyl group by the N3 group at the C-3 position of (3R,4R,5R)-ethyl 4-hydroxy-5-(methoxymethoxy)-3-(pentan-3-yloxy)cyclohex-1-enecarboxylate4and at the C-4 position of (3R,4S,5R)-ethyl 4-acetamido-5-hydroxy-3-(pentan-3-yloxy)cyclohex-1-enecarboxylate7successfully served as the key steps.

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Graphical contents list

January 26, 2012

Publication year: 2012 Source: Tetrahedron Letters, Volume 53, Issue 9, 29 February 2012, Pages 995-1007 [No author name available]

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Erratum to “Questions about the structures of nitraraine and nitraraidine” [Tetrahedron Lett.2011,52, 6453–6456]

January 24, 2012

Publication year: 2012 Source: Tetrahedron Letters, Available online 21 January 2012 Rim Salame, Edmond Gravel, Erwan Poupon

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Facile preparation and reactivity of bifunctional ionic liquid-supported hypervalent iodine reagent: a convenient recyclable reagent for catalytic…

January 22, 2012

Publication year: 2012 Source: Tetrahedron Letters, Available online 21 January 2012 Chenjie Zhu, Akira Yoshimura, Yunyang Wei, Victor N. Nemykin, Viktor V. Zhdankin Novel, efficient and recyclable bifunctional catalysts bearing ionic liquid supported (2,2,6,6-tetramethylpiperidin-1-yl)oxyl (TEMPO) and iodoarene moieties were developed and used for environmentally benign catalytic oxidation of alcohols. The reactions using peracetic acid as a green and practical co-oxidant afforded the corresponding carbonyl compounds in high yields under mild conditions and convenient work-up. Furthermore, these ionic liquid supported bifunctional catalysts could be simply recovered and reused

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Catalytic C-H Arylation of Unactivated Heteroaromatics with Aryl Halides by Cobalt Porphyrin

January 22, 2012

Publication year: 2012 Source: Tetrahedron Letters, Available online 21 January 2012 Ying Ying Qian, Ka Lai Wong, Meng Wen Zhang, Tsz Yiu Kwok, Ching Tat To, … Direct C-H arylation of unactivated heteroaromatics with aryl halides catalyzed by cobalt porphyrin is reported. The reaction is proposed to go through a homolytic aromatic substitution reaction

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Synthetic studies related to MPC1001: formation of a model epidithiodiketopiperazine

January 22, 2012

Publication year: 2012 Source: Tetrahedron Letters, Available online 21 January 2012 Lihong Wang, D.L.J. Clive A tricyclic epidithiodiketopiperazine was prepared having structural features related to the antitumor antibiotic MPC1001. The method is based on the use of the sulfenylating agentp-MeC6H4S(O2)SCH2OSiMe2Bu-tto introduce two protected sulfur atoms in a sequential and stereocontrolled manner

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Biyoulactones D and E, meroterpenoids fromHypericum chinense

January 22, 2012

Publication year: 2012 Source: Tetrahedron Letters, Available online 20 January 2012 Naonobu Tanaka, Shuhei Abe, Jun’ichi Kobayashi Two new meroterpenoids, biyoulactones D (1) and E (2) were isolated from the roots of Hypericum chinense, and their structures were elucidated on the basis of spectroscopic data and conformetional analysis. Biyoulactones D (1) and E (2) are structurally unique tricyclic meroterpenoids having an octahydroindene ring, a γ-butyrolactone ring, and a β-diketone moiety.

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Synthesis of a novel class of steroidal tetrazolo[1,5-a]pyridinesviaintramolecular 1,3-dipolar cycloadditions

January 22, 2012

Publication year: 2012 Source: Tetrahedron Letters, Available online 20 January 2012 Junali Gogoi, Pranjal Bezbaruah, Pallabi Saikia, Junali Goswami, Pranjal Gogoi, … A facile synthesis of a novel class of steroidal A/B/D-ring annulated tetrazolo[1,5-a]pyridine derivatives has been accomplishedviaintramolecular 1,3-dipolar cycloaddition reaction of azide with nitrile in aprotic solvent. The synthesis of D-ring annulated tetrazolo[1,5-a]pyridine in alcohol showed incorporation of an alcohol molecule into heterocyclic system

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Synthesis of 1-aryl-substituted-4-chloroimidazo[1,2-a]quinoxalines catalyzed by PdCl2in water

January 22, 2012

Publication year: 2012 Source: Tetrahedron Letters, Available online 20 January 2012 Mohammad Bakherad, Ali Keivanloo, Shahrzad Samangooei The reaction of 2-chloro-3-propargylaminoquinoxaline with various aryl iodides and bromides catalyzed by Pd–Cu in the presence of potassium carbonate as the base in water leads to the one-pot formation of 1-aryl-substituted-4-chloroimidazo[1,2-a]quinoxalines in moderate-to-high yields. The reaction of 2-chloro-3-propargylaminoquinoxaline with various aryl iodides and bromides catalyzed by Pd–Cu in the presence of potassium carbonate as the base in water leads to the one-pot formation of 1-aryl-substituted-4-chloroimidazo[1,2- a ]quinoxalines in moderate-to-high yields.

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The challenge of choosing environmental indicators of anthropogenic impacts in estuaries

January 21, 2012

Publication year: 2012 Source: Environmental Pollution, Volume 163, April 2012, Pages 207-217 Katherine A. Dafforn, Stuart L. Simpson, Brendan P. Kelaher, Graeme F. Clark, Valeriya Komyakova, … Ecological assessments over large spatial scales require that anthropogenic impacts be distinguishable above natural variation, and that monitoring tools are implemented to maximise impact detection and minimise cost.

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