• Title/Summary/Keyword: Pyrrolidines

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Synthesis of 2,5-Disubstituted Pyrrolidines from N-Alkenyl and Alkynyl N-Benzoyloxysulfonamides Catalyzed by (CuOTf)2・C6H6

  • Liu, Wei-Min;Liu, Zhen-Hong;Cheong, Wei-Wen;Priscilla, Lu-Yi Teo;Li, Yongxin;Narasaka, Koichi
    • Bulletin of the Korean Chemical Society
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    • v.31 no.3
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    • pp.563-569
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    • 2010
  • A new synthetic method of 2,5-disubstituted pyrrolidines is developed by the cyclization of unsaturated N-benzoyloxysulfonamides by $(CuOTf)_2{\cdot}C_6H_6$ in refluxing dichloroethane. Various N-4- and N-5-alkenyl and alkynyl N-benzoyloxysulfonamides are cyclized to give pyrrolidines. The cyclization proceeds via addition of sulfonamidoyl radicals to intramolecular unsaturated bonds or allylic hydrogen abstraction with the radical intermediates.

Ring Opening of Pyrolidine and Formation of N-Protected Amino Ketones; Synthesis of 5-Amino-2-pentanone Derivatives (피롤리딘의 개환과 N-프로텍티드 아미노 케톤의 형성; 5-아미노-2-펜타논 유도체의 합성)

  • Park, Myung-Sook
    • YAKHAK HOEJI
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    • v.40 no.3
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    • pp.300-305
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    • 1996
  • The base-induced elimination of N-protected 2-(bromomethyl)pyrrolidines 12a-c with KHMDS in THF at -78$^{\circ}C$ for 1h gave exocyclic enamines 13a-c. The acidic catalyzed pr otonation on ${\beta}$-carbon atom of 2-(methylene)pyrrolidines 13a-c with $H_3PO_4$ formed endocyclic N-iminium intermediates 14(or 15). Nucleophilic attack of alpha-carbon atom and hydrolysis of N-iminium ion gave carbocationic adduct (aminoalcohol) 16 from which 5-amino-2-pentanones 17a-c were formed after deprotonation.

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O-Alkylation Using Ag2O; Synthesis of Novel 4-Alkyloxy-2-phenylcarboxamidyl-1-tosylpyrrolidines (산화은을 이용한 O-알킬화 반응; 새로운 4-알킬옥시-2-페닐카복사미딜-1-토실피롤리딘 유?체의 합성)

  • Park, Myeong Suk
    • Journal of the Korean Chemical Society
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    • v.45 no.6
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    • pp.549-554
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    • 2001
  • For the development of new COX-2 inhibitor, novel compound were synthesized through induction an arylsulfonyl group to 1-position, an arylcarboxamidyl group to 2-position and an alkyl group to 4-position of L-proline. We started from 4-hydroxy-L-proline, the 4-methylphenylsulfonyl of 1-position was introduced through N-tosylation and the carboxylic acid group was protected by esterification. We sucessfully converted to a various derivatives 4b-d for O-alkyl-(or aralkyl)ation of 4-position using silver oxide as catalysis. The 4-alkyloxy-1-tosyl L-prolines 5b-d were synthesized through base-hydrolysis for the deprotection of carboxylic acid. Final compound 1,2,4-substituted pyrrolidines, 4-alkyloxy-2-phenylcarboxamidyl-1-tosyl pyrrolidines 6a-d were synthesized through the condensation of arylamine with 3 and 5b-d using DCC.

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Total synthesis of 1,4-Dideoxy-1,4-Imino-D-Arabinitol(DABl)

  • Kim, In-Su;Jung, Young-Hoon
    • Proceedings of the PSK Conference
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    • 2003.10b
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    • pp.178.2-178.2
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    • 2003
  • Naturally occurring sugar mimics with a nitrogen in the ring are classified into five structural classes: polyhydroxylated pyrrolidines, piperidines, indolizidines. pyrrolizidine, and nortropanes. Glycosidase are involved in a wide range of important biological processes, such as intestinal digestion, post-translational processing of glycoproteins and the lysosomal catabolism of glycoconjugate. The realization that alkaloidal sugar mimics might have enormous therapeutic potential in many diseases such as viral infection, cancer and diabetes has led to increasing interest and demand for these compounds. (omitted)

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Asymmetric Total Synthesis of the Glycosidase Inhibitor, 1,4-dideoxy-l,4-imino-D-arabinitol(DAB1)

  • Kim, In-Su;Hoon, Jung-Young
    • Proceedings of the Korean Society of Applied Pharmacology
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    • 2003.11a
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    • pp.115-115
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    • 2003
  • Naturally occurring sugar mimics with a nitrogen in the ring are classified into five structural classes: polyhydroxylated pyrrolidines, piperidines, indolizidines. pyrrolizidine, and nortropanes. Glycosidase are involved in a wide range of important biological processes, such as intestinal digestion, post-translational processing of glycoproteins and the lysosomal catabolism of glycoconjugate. The realization that alkaloidal sugar mimics might have enormous therapeutic potential in many diseases such as viral infection, cancer and diabetes has led to increasing interest and demand for these compounds. Most of these effects can be shown to result from the direct or indrect inhibition of glycosidases.

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