• YAKHAK HOEJI
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• v.41 no.1
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• pp.18-21
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• 1997

Synthesis of an optically active azabicyclo[3.2.1]octane skeleton as a backbone of the tropane alkaloids has been achieved by employing intramolecular Mannich reaction. Utilizat ion of (R)-${\alpha}$-methylbenzylamine as a chiral auxiliary provided an excellent cyclization of amino dioxolane precursor. However, this auxiliary did not afford high asymmertic induction for the preparation of the optically active cyclization precursor.

• YAKHAK HOEJI
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• v.35 no.3
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• pp.231-235
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• 1991

Compounds of the structure of -4,9-dione are known to have an antibacterial activity against Gram-positive bacteria. New kinds of 2-amino-$\alpha$-cyano-$\alpha$-ethoxycarbonyl-niethyl)-1,4-naphthoquino ne was reacted with some alkylamines(methylamine, ethylamine, ethanolarnine, isopropylamine, cyclohexylamine, benzylamine) to yield 2-amino-3-ethoxycarbonyl-N-alkyl-4,9-diones.

• 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.

• Proceedings of the PSK Conference
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• 2002.04a
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• pp.181.3-182
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• 2002

• Bulletin of the Korean Chemical Society
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• v.16 no.9
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• pp.892-893
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• 1995

• Bulletin of the Korean Chemical Society
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• v.7 no.3
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• pp.254-255
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• 1986

• Proceedings of the PSK Conference
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• 2000.10a
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• pp.214.2-214.2
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• 2000

• Bulletin of the Korean Chemical Society
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• v.22 no.9
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• pp.999-1004
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• 2001

(1-Chloro-2,2-dicyanovinyl)benzene or 1,4-bis(1-chloro-2,2-dicyanovinyl)benzene was reacted with 2-amino-phenol to give the model compound, hydroxy enaminonitrile, which was found to undergo thermal cyclization reaction to form the corresponding benzoxazole. This intramolecular cyclization reaction is expected to occur through nucleophilic attack to electropositive enamine carbon by ortho-hydroxy group on the phenyl ring, which is accompanied by the release of neutral malononitrile through rearrangement. From each bifunctional monomer, o-hydroxy substituted polyenaminonitrile was prepared and characterized as a new precursor polymer for well-known aromatic polybenzoxazole. Also the unusual macrocyclic dimer formation from the 1,4-bis(1-chloro-2,2-dicyanovinyl)benzene and 2,2-bis(3-amino-4-hydroxyphenyl)hexafluoropropane polymerization reaction system was discussed. The thermal cyclization reactions and the properties of polymers were investigated using FT-IR and thermal analysis (DSC & TGA).

• Textile Coloration and Finishing
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• v.7 no.4
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• pp.39-44
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• 1995

A study has been made about some correlations in the chemical cyclization of precursors, poly(ether-amide-amic acid)s by treating in solution a mixture of acetic anhydride and pyridine in the presence of 4,4-dimethyl formamide, with the poly(ether-amic acid)s being respectively reacted between trimellitic anhydride chloride and 3 kinds of diamines, i.e., 4,4'-bis(m-aminophenoxy) benzophenone, 2,2'-bis[4-(m-aminophenoxy) phenyl] propane and 4,4'-bis(m-aminophenoxy) diphenyl sulfone. The cyclization of imide ring in the poly(ether-amide-amic acid)s may be regarded as an intramolecular acylation of amide group by o-carboxyl group. As a result of this reseach, the effects on the conversion to poly(ether-amide-imide)s have been found by changing the ratio of cosolvents in the cyclization mixture.

• Journal of the Korean Chemical Society
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• v.48 no.4
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• pp.451-455
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• 2004