• YAKHAK HOEJI
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• v.38 no.6
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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.

• Biomolecules & Therapeutics
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• v.7 no.2
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• pp.164-169
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• 1999

The synthesis and antimicrobial activity of N-substituted glycol derivatives of Norfloxacin were described. Norfloxacin was treated with chloroacetyl chloride to yield chloroacetyl norfloxacin (1). This compounds was reacted with alkyldiamines to afford bivalent ligand quinolone carboxylic acids (2-6), which was added to pivaloyloxymethyl chloride to give bivalent ligand pivaloyloxymethyl quinolone carboxylates (7-11). Chloroacetyl norfloxacin (1) treated with alkylamines to obtain monovalent ligand quinolone carboxylic acids (12-15), which was reacted with pivaloyloxymethyl chloride to get monovalent ligand pivaloyloxymethyl quinolone carboxylates (16-19). Free carboxylic quinolones (2-6, 12-15) showed little stronger activities to their pivaloyloxymethyl esters (7-11, 16-19). In monovalent ligand quinolone analogues, longer a1kyl chain com-pounds showed stronger activities than shorter one.

• Analytical Science and Technology
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• v.8 no.4
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• pp.449-456
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• 1995

Novel macrocyclic ligands modified with pendant arms, N, N', N'', N''', N'''', N'''''-hexakis(2-aminoethyl)-1, 4, 7, 10, 13, 16-hexaazacyclootadecane [$L_3$, Fig.1] and 1, 4, 7-tris(3-(o-hydroxyphenyl)propyl)-1, 4, 7-triazacyclononane [$L_4$, Fig.1] have been synthesized, and the protonation of $L_3$ and $L_4$ and stability constants of $L_3$ with bivalent transition metal ions and rare earth metal ions were determined by a potentiometry. The obtained results show that the complex formation of $L_3$ depends on the metal ligand ratios, and the stability of the metal complexes does not depend on the sizes of the metal ions, but on the nature of the metal ions. The structures of the rare earth complexes for $L_4$ were characterized by an X-ray absorption spectrometry(XAFS).

• Microbiology and Biotechnology Letters
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• v.17 no.3
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• pp.193-197
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• 1989

The three new Alkylene bisdithionreido $\beta$-lactam derivatives were synthesized and evaluated for antimicrobial activities. Treatment of cefadroxil.2DMF with alkylene diisothiocyanate which was obtained by the reaction of alkylene diamine with carbon disulfide, sodium hydroxide and ethyl chloroformate afforden alkylene bisdithioureido $\beta$ -lactam derivatiives. The antimicrobial activities of the compounds synthesized were ethylene bisdithioureido $\beta$-lactam derivative lost the sensitivity against Escherichia coli but showed potent antimicrobial activity against $\beta$-lactams Escherichia coli, but, tetramethylene bisdithioureido $\beta$-lactam derivative and hexamethylene bisdithioureido $\beta$ -lactam derivative compounds showed diminished or no antimicrobial activities.