acknowledgments

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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Synthetic studies on (+)-bucidarasin C: two diastereoselective transannular reactions producingcis-decaline derivatives that show reversal selectivity

January 24, 2012

Publication year: 2012 Source: Tetrahedron Letters, Available online 24 January 2012 Akinobu Nakahara, Misaki Kanbe, Masahisa Nakada This manuscript describes studies on the construction of thecis-decaline core of (+)-bucidarasin C.

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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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A versatile approach to the regioselective synthesis of diverse (-)-epicatechin- β -D-glucuronides

January 22, 2012

Publication year: 2012 Source: Tetrahedron Letters, Available online 20 January 2012 Eric S. Mull, Michael VanZandt, Adam Golebiowski, Paul Beckett, Pradeep K. Sharma, … A versatile new approach is reported for the total synthesis of five glucuronide metabolites of epicatechin, using selective protection/deprotection techniques

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Palladium-catalyzed site-selective arylation of symmetric dichlorobenzaldehyde to non-symmetric diaryl benzaldehydeviaSuzuki coupling

January 22, 2012

Publication year: 2012 Source: Tetrahedron Letters, Available online 20 January 2012 Raju Dey, Brindaban C. Ranu Arylation of 2,6-dichlorobenzaldehyde by aryl boronic acidsviasite-selective Suzuki coupling catalyzed by PdCl2supported on 4Å molecular sieves produces 2-aryl-6-chlorobenzaldehyde which on subsequent coupling with a different aryl boronic acid in presence of Pd(OAc)2– NHC ligand leads to non-symmetric diaryl benzaldehyde in good overall yield.

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An efficient synthesis of the 4’-epimer of 2-fluoronoraristeromycin

January 22, 2012

Publication year: 2012 Source: Tetrahedron Letters, Available online 20 January 2012 Quachel Bazile, Tesfaye Serbessa, Junyan Zhong The 4’-epimer of 2-fluoronoraristeromycin was synthesized by employing bis-t-butoxycarbonyl (Boc) protected 2-fluoroadenine as a superior substrate for the Mitsunobu reaction with the appropriate cyclopentenol.

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Copper catalyzedipso-nitration of iodoarenes, bromoarenes and heterocyclic haloarenes under ligand-free conditions

January 22, 2012

Publication year: 2012 Source: Tetrahedron Letters, Available online 21 January 2012 P.J. Amal Joseph, S. Priyadarshini, M. Lakshmi Kantam, H. Maheswaran A catalytic protocol for the conversion of haloarenes into the corresponding nitroarenes is presented using copper salts under ligand-free conditions. The method was effectively utilized for theipso-nitration of a broad variety of haloarenes that includes iodoarenes, bromoarenes and heterocyclic haloarenes.

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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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First synthesis of 1-(indol-2-yl)azulenes by the Vilsmeier-Haack type arylation with triflic anhydride as an activating reagent

January 20, 2012

Publication year: 2012 Source: Tetrahedron Letters, Available online 19 January 2012 Taku Shoji, Yuta Inoue, Shunji Ito Azulene derivatives reacted with 2-indolinones in the presence of triflic anhydride (Tf2O) to afford 1-(indol-2-yl)azulenes in good yields. In the cases of the reaction of 6-tert-butyl-1-(methylthio)azulene (11) and 1-(1,4-dihydropyridin-4-yl)azulene14, 1,1’-biazulene derivative24and 1-(indol-2-yl)azulene (2) were obtained under the similar reaction conditions, respectively, instead of the presumed electrophilic substitution products

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