• Bulletin of the Korean Chemical Society
• /
• v.25 no.4
• /
• pp.501-505
• /
• 2004

Esterification of aliphatic or aromatic carboxylic acids with alcohols using 2-(4-nitrobenzenesulfonyl)-4,5-dichloropyridazin-3(2H)-one (3) in the presence of base in organic solvents gave the corresponding esters in excellent yields

• YAKHAK HOEJI
• /
• v.38 no.6
• /
• pp.677-682
• /
• 1994

A number of 7-[3-hydroxy-(4-methylthio or 3-methylthiomethyl)pyrrolidinyl]quinoline-3-carboxylic acids were synthesized by condensation of 7-fluoro substituted quinoline-3-carboxylic acid with 3-hydroxy-4-methylthiopyrrolidine or 3-hydroxy-4-methylthiomethylpyrrolidine. The in vitro antimicrobial activity of them were tested against twenty species of Gram-positive or Gram-negative microorganisms. It showed remarkable antibacterial activity, particularly against Gram-positive microorganisms. Among those 1-cyclopropyl-5-amino-6,8-difluoro 7-(3-hydroxy-4-methylthiomethylpyrrolidinyl)-1,4-dihyd ro-4-oxo-3-quinolinecarboxylic acid(12d) and 1-cyclopropyl-6-fluoro-8-methoxy-7-(3-hydroxy-4-methylthiometby1pyrrolinyl)-1,4-dihydro-4-oxo-3-quinolinocarboxylic acid(12g) showed the most potent in vitro antibacterial activity, and 12d showed better antibacterial activity against MRSA compared to ciprofloxacin and sparfloxacin.

• YAKHAK HOEJI
• /
• v.38 no.5
• /
• pp.520-524
• /
• 1994

A number of 7-[(3-methylthio or methylthiomethyl)-3-pyrrolinyl] quinolone-3-carboxylic acids were synthesised by condensation of 7-fluoro substituted quinolone-3-carboxylic acid with 3-methylthio-3-pyrroline or 3-methylthiomethyl-3-pyrroline. The in vitro antimicrobial activity of them were tested against twenty species of Gram-positive or Gram-negative microorganisms. It showed remarkable antibacterial activity, particularly against Gram-positive microoganisms. Among those 1-cyclopropyl-6,8-difluoro-7-[(3-methylthiomethyl) -3-pyrrolinyl]-1,4-dihydro-4-oxo-3-quinolinecarboxylic acid(12a) and 1-cycl opropyl-6-fluoro-8-chlore-7-[(3-methylthiomethyl)-3-pyrrolinly]-1,4-dihydro-4-oxo-3-quinolinecarboxylic acid(12b) showed the most potent in vitro antibacterial activity.

• Journal of the Korean Chemical Society
• /
• v.47 no.5
• /
• pp.530-532
• /
• 2003

• YAKHAK HOEJI
• /
• v.10 no.2_3
• /
• pp.8-11
• /
• 1966

항인결핵균성및 streptomycin, isoniazid및 para-aminosalicylic acid에 대한 내성인결핵균주에 현저한 항균작용 있는 dextro-2,2'-(ethylenediimino)-di-1- butanol(Ethambutol) 계열 및 thioureido(-NHCSNH-) 함유화 합물 계열인 2,2'-(ethylenediimino)-di-1-butyric acid및 2,2'-(thioureido)-di-1-butyric acid를 합성했으며 이들 약물의 구조와 작용간의 상호관계를 설명코저 이들 화합물과 류사한 구조인 2,2'-(thioureido)-di-acetic acid를 합성했기에 보고함.

• YAKHAK HOEJI
• /
• v.43 no.4
• /
• pp.442-446
• /
• 1999

The synthesis and antimicrobial activity of N-substituted glycyl derivatives of Norfloxacin were described. Norfloxacin was treated with chloroacetyl chloride to yield chloroacetyl norfloxacin (1). This compounds was treated with alkylamines to obtain quinolone carboxylic acids (2-6), which were reacted with pivaloyloxymethyl chloride to get pivaloyloxymethyl quinolone carboxylates (7-11). Free carboxylic quinolones (2-6) showed little stronger activities to their pivaloyloxymethyl esters (7-11). In quinolone analogues, longer alkyl chain compounds showed stronger activities than shorter one.

• Archives of Pharmacal Research
• /
• v.28 no.11
• /
• pp.1219-1223
• /
• 2005

6-[2-(Benzoxazol-2-ylmethylamino)ethoxy]-1-alkyl-1H-indole-2-carboxylic acids were designed and synthesized as $\beta$-amyloid (A$\beta$) fibril assembly inhibitors. Their inhibitory activity on A$\beta$, aggregation was evaluated by thioflavin T assay although their activities were insignificant.

• Journal of the Korean Chemical Society
• /
• v.41 no.4
• /
• pp.214-218
• /
• 1997

• Bulletin of the Korean Chemical Society
• /
• v.11 no.5
• /
• pp.376-379
• /
• 1990

To find out a correlation between antibacterial activity and physical properties of 7-substituted 1-ethyl-6-fluoro-1,4-dihydro-4-oxoquinoline-3-carboxylic acid, dipole moments, charge distributions, and hydrophobicities were calculated. The atomic charges and the dipole moments to not give any correlations with inhibition of DNA gyrase, but the calculated hydration free energies show some correlations.

• Bulletin of the Korean Chemical Society
• /
• v.15 no.6
• /
• pp.448-452
• /
• 1994

2-Hydroxymethyl-2,5-dihydrothiophene 1,1-dioxide (1) was prepared from thiophene-2-carboxylic acid by consecutive reactions involving the Birch reduction, esterification, reduction with lithium aluminum hydride, and oxidation with Oxone$^{\circledR}$. The esterification of alcohol 1 with various unsaturated carboxylic acids provided the precursors 8 for the intramolecular Diels-Alder reaction. The cheletropic expulsion of sulfur dioxide from the esters 8 followed by intramolecular Diels-Alder reaction furnished bicyclic ${\gamma}$-and ${\delta}$-lactones.