• 한국자기공명학회논문지
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• 제3권1호
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• pp.52-59
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• 1999

Authors synthesized common intermediates which are applicable for potential antibiotics. Their complete 13C and 1H NMR chemical shift data as well as carbon-and proton-fluorine coupling constants are reported. The knowledge of proton and carbon-fluorine coupling constants may help one assign the NMR data of the fluorinated quinolone derivatives. These results agree with the data published previously.

• 약학회지
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• 제38권6호
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• pp.721-724
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• 1994

According to computer graphics/Grid search analysis, ${\beta}-keto$ carboxylic acid of nalidixic acid which has an antibacterial activity as DNA-gyrase inhibitor has been known to have got four different conformational energy values. In orders, the energy value of conformation A,B,C and D was -6.603, -4.114, -1.766 and 7.327 kcal/mol. The difference of energy value between conformation A and D was 13.9 kcal/mol. Usually conformation C was used in literature. However, it had a energy value of -1.766 kcal/mol as the result of the analysis which is about 5 kcal/mol higher than the most stable conformation A. Therefore, conformation A is expected to be more stable than conformation C.

• 약학회지
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• 제38권6호
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• pp.664-672
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• 1994

Eighteen new hybrid bivalent ligand quinolones that contain two different type of pharmacophores in a single molecule were prepared and evaluated for in viかo antibacterial activity. Hybrid bivalent ligands p-nitrobenzyloxycarbonyl quinolones were prepared by the treatment of active esters of succinyl fluoroquinolones with 1,7-disubstituted fluoroquinolone carboxylic acids in DMF. Eighteen final quinolone carboxylic acids were obtained by the reduction of compounds $25{\sim}42$ with hydrogen in the presence of 10% Pd-C. Among these derivatives, compound[56] showed the most potent antibacterial activity against a wide range of microoranisms.

• 지식경영연구
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• 제2권1호
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• pp.109-132
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• 2001

The purpose of this article is to develop a dynamic model of organizational capabilities and knowledge creation, and at the same time identify the organizational capability factors for effective knowledge creation, by empirically analyzing the history of new Quinolone antibacterial drug compound (LB20304a) discovery process at LG, as a case in point. Major findings of this study are as follows. First, in a science-based area such as drug development, the core of successful knowledge creation lies in creative combination of different bodies of scientific explicit knowledge. Second, the greater the difficulty of learning external knowledge, the more tacit knowledge is needed for the recipient firm to effectively exploit that knowledge. Third, in science-based sector such as pharmaceutical industry, the key for successful knowledge creation lies in the capability of recruiting and retaining star scientists. Finally, for effective knowledge creation, a firm must keep its balance among three dimensions of organizational capabilities: local, process, architectural capabilities.

• 약학회지
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• 제43권4호
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• pp.437-441
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• 1999

Enoxacin[1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(1-\piperazinyl)-1,8-naphthyridine-3-carboxylic acid, ENX] is a new quinolone antibacterial agent. The method is based on the highly colored charge-transfer complex formation of this drug as a $\pi$-electron donor with 7,7,8,8-tetracyanoquinodimethane(TCNQ) or chloranil(CL) as $\pi$-acceptors. The colored products were measured spectrophotometrically at 842 nm and 552 nm for TCNQ and CL, respectively. The different experimental conditions are optimized. The linearities for TCNQ and CL were $1.6{\;}\mu\textrm{g}/mL~32{\;}\mu\textrm{g}/mL$ and $6.4{\;}\mu\textrm{g}/mL~160{\;}\mu\textrm{g}/mL$, respectively and colors were produced in non-aqueous media. This report describes a simple and ra\pid method for the analysis of enoxacin.

• 약학회지
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• 제35권6호
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• pp.515-521
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• 1991

A number of 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(4-substitutedcarbamyl-1-piperazinyl) quinoline [or 1,8-naphthyridine]-3-carboxylic acid and their pivaloyloxymethyl esters were prepared. The compounds synthesized were evaluated for antibacterial activity in vitro against Escherichia coli, Bacillus subtilis, Proteus vulgaris, Klebsiella pneumoniae, Staphylococcus aureus and Pseudomonas aeruginosa. Among those 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(4-methylcarbamyl-1-piperazinyl) quinoline-3-carboxylic acid [1] and 1-ethyl-6-fluoro-1,4-dihydro-4-oxo-7-(4-methylcarbamyl-1-piperazinyl)1,8-naphthyridine-3-carboxylic acid [6] showed the most potent in vitro antibacterial activity.

• Bulletin of the Korean Chemical Society
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• 제17권2호
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• pp.147-152
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• 1996

To see the quantitative relationship between the structures of the C-7 substituted quinolones and their antibacterial activities, theoretical parameters such as the molecular van der Waals volume, surface area and some electrostatic parameters based on the molecular electrostatic potential, which represent lipophilicity, and some quantum mechanical parameters are introduced as descriptors. The sixteen substituted quinolone derivatives and twenty bacteria are used for the study. It is found that the QSARs of C-7 substituted quinolones are obtained for eleven bacteria and our descriptors are more useful for Gram positive organisms than negative ones. It is also shown that molecular surface area (or molecular Waals volume) of the C-7 substituent and net charge of C-7 atom of the quinolones are the descriptors of utmost importance.

• 대한약학회:학술대회논문집
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• 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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• pp.70.2-71
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• 2003

Quinolone resistance in Streptococcus pneumoniae is related to mutations in the DNA gyrase and topoisomerase IV genes. DW-286a displayed potent activity against S. pneumoniae C9211 (MIC, 0.015 ${\mu}$g/ml) compared with gemifloxacin (MIC, 0.06 ${\mu}$g/ml). This study was performed to analyze the ability of DW-286a to cause resistance development in S. pneumoniae and to establish whether DNA gyrase or topoisomerase IV is primary target. DW-286a resistant mutants of S. pneumoniae C9211 were generated by stepwise selection at increasing drug concentration. (omitted)

• 한국응용약물학회:학술대회논문집
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• 한국응용약물학회 2001년도 추계학술대회 및 정기총회
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• pp.37-40
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• 2001

• 대한약학회:학술대회논문집
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• 대한약학회 2000년도 춘계총회 및 학술대회
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• pp.64-65
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• 2000