• Proceedings of the PSK Conference
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• 2000.04a
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• pp.162.3-163
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• 2000

• Bulletin of the Korean Chemical Society
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• v.12 no.3
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• pp.347-348
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• 1991

• Journal of the Korean Chemical Society
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• v.33 no.6
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• pp.677-678
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• 1989

• Bulletin of the Korean Chemical Society
• /
• v.24 no.7
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• pp.1009-1010
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• 2003

• YAKHAK HOEJI
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• v.47 no.5
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• pp.288-292
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• 2003

The synthesis of new 6-exomethylene penams with substituted triazole ring was described. The 6,6-dibromopenam 5 was reacted with $CH_3$MgBr and substituted triazole 4 to afford the 6-bromo penicillanate 6, which was treated with acetic anhydride to give acetoxy compound 7. The deacetobromination of acetoxy compound 7 with zinc and acetic acid gave 6-exomethylene penams 8, which was oxidized to sulfones 9 by m-CPBA. The p-methoxybenzyl compounds 6∼9 were deprotected by AlCl$_3$ and neutralized to give the sodium salts 10∼13.

• YAKHAK HOEJI
• /
• v.44 no.2
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• pp.128-134
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• 2000

The synthesis of new 6-exomethylene penams with triazole ring was described. The 6,6-dibromopenam 5 was treated with $CH_3$MgBr and carbaldehyde 4 to afford the 6-bromo-6-(1-hydroxy-1-methyl)penicillanate 6, which was reacted with acetic anhydride to give acetoxy compound 7. The deacetobromination of 7 with zinc and acetic acid gave 6-exomethylenpenams, Z-isomer 8 and E-isomer 9, which were oxidized to sulfones 10 and 11 by m-CPBA. The p-methoxybenzyl compounds 6~11 were deprotected by AlCl$_3$ and neutralized to give the sodium salts 12~17.

• YAKHAK HOEJI
• /
• v.48 no.5
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• pp.303-308
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• 2004

The synthesis of new 6-triazole exomethylenepenams was described. The 6,6-dibromopenam 5 was reacted with $CH_3$MgBr and substituted triazole 4 to afford the 6-bromo penicillanate 6, which was treated with acetic anhydride to give acetoxy compound 7. The deacetobromination of acetoxy compound 7 with zinc and acetic acid gave 6-exomethylene penams 8 and 9, which were oxidized to sulfones 10 and 11 by m-CPBA. The p-methoxybenzyl compounds 6-11 were deprotected by AlCl$_3$ and neutralized to give the sodium salts 12-17.

• Journal of the Korean Electrochemical Society
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• v.3 no.1
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• pp.57-62
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• 2000

Sulfonated Polysulfone (SPSF) cation-exchange membranes were synthesized by introducing various ratio of chlorosulfuric acid (CSA) onto the main chain of polysulfone (PSF). Properties such as ion exchange capacity, water content, liked ion concentration, and partition coefficient were measured, respectively. Through the analysis of DSC and TGA, it has been shown that glass transition temperature increased and weight loss decreased as sulfuric acid group concentration increased. Structure of membrane measured by AFM and SEM was seen to be asymmetric. Apparent diffusion coefficient of sodium ions through SPSF membrane by AC impedance was increased as sulfuric acid group concentration increased.

• YAKHAK HOEJI
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• v.46 no.6
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• pp.381-386
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• 2002

The synthesis of new 6-exomethylene sulbactam derivatives with 5-methyl-1,3,4-thiadiazole was described. The 6,6-dibromopenam 5 was reacted with $CH_3$MgBr and carbaldehyde 4 to afford the 6-bromo-6-(1-hydroxy-1-methyl)penicillanate 6, which was treated with acetic anhydride to give acetoxy compound 7. The deacetobromination of acetoxy compound 7 with zinc and acetic acid gave 6-exomethylen penams, Z-isomer 8 and E-isomer 9, which was oxidized to sulfones 10 by m-CPBA. The p-methoxybenzyl compounds 6-10 were deprotected by AlCl$_3$ and neutralized with NaOH solution to give the sodium salts 11-15.

• Proceedings of the Korean Society of Applied Pharmacology
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• 1994.04a
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• pp.230-230
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• 1994

Human leukocyte elastase(HLE)는 폐와 피부, 혈관등의 Connective tissue의 주요 구성물인 elastin을 분해하는 효소로써, 백혈구의 식균작용에도 관여한다. 그러나 이효소가 과다하게 분비되면 pulmonary emphysema와 adult respiratory distress syndrome, rheumatoid arthritis를 유발한다고 알려지고 있다. 지금까지 HLE억제제로 시판되는 의약품은 없으나, 최근에 Cephalosporin유도체가 이 효소의 억제제로 우수한 효과가 있다는 보고가 있은 후, HLE억제제로써 이들의 유도체가 개발되고 있다. 연구자들은 다음일반식에서 2번과 3번위치에 치환기를 도입시킨 수종의 Cephalosporin Sulfone의 유도체들을 합성하고. 이들의 HLE억제 효과를 Spectrophotometerqkdtlr을 이용하여 측정하였다. 합성화합물증 몇가지는 우수한 HLE억제효과를 보여주었고, 2번위치에 diphenylcyclopropyl ring과 같은 부피가 큰 치환체를 도입하면 효소억제력이 증가되었다.