- Ofloxacin preparation method (by machine translation)
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The invention provides a preparation method of ofloxacin. The preparation method comprises the following steps of: reacting (N,N)-dimethylamino ethyl acrylate with aminopropanols in methylbenzene; directly adding lewis base serving as a catalyst and trimethylchlorosilane to protect hydroxyl and amido; after reaction is completely finished, dropwise adding (2,3,4,5)-tetrafluorobenzoyl chloride; preserving heat; performing acid washing; removing protecting groups; concentrating an organic layer to obtain an oil layer; adding a proper amount of dimethyl formamide (DMF); diluting and dropwise adding backflow DMF having anhydrous potassium fluoride; recovering DMF and adding water to centrifuge; adding acid water into a solid to hydrolyze to obtain difluorocarboxylic acid; and completely reacting difluorocarboxylic acid and N-methyl piperazine in dimethylsulfoxide (DMSO) by using triethylamine as an acid-binding agent at 90-100 DEG C to obtain ofloxacin. According to the process, hydroxyl and amido are protected by using trimethylchlorosilane, so that the utilization degree of (2,3,4,5)-tetrafluorobenzoyl chloride is effectively increased, and the generation of impurities is reduced to ensure that the reaction yield of intermediate difluorocarboxylic acid is increased by 10 percent.
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Paragraph 0014; 0043; 0044
(2016/10/09)
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- Baylis-Hillman route to several quinolone antibiotic intermediates
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Treatment of methyl propiolate and 2,4,5-trifluoro-, 2-fluoro-, 2-fluoro-5-methoxy- or 2,3,4,5-tetrafluorobenzaldehydes with a ZrCl 4/Bu4NI combination induces an aldol reaction to furnish β-iodo-α-(hydroxyalkyl)acrylates. These can be used for the preparation of several quinolone intermediates, 1-substituted 4-oxo-1,4-dihydroquinoline-3-carboxylic acids and 9,10-difluoro-3-methyl-2,3- dihydro-7-oxo-7H-pyrido[1,2,3-de][1,4]benzoxazine-6-carboxylic acid through the oxidation, amination and hydrolysis reactions. Georg Thieme Verlag Stuttgart.
- Hong, Wan Pyo,Lee, Kee-Jung
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p. 963 - 968
(2007/10/03)
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- Novel oxazolidinone-quinolone hybrid antimicrobials
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Antimicrobial compounds incorporating oxazolidinone and quinolone pharmacophore substructures have been synthesized and evaluated. Representative analogues 2, 5, and 6 display an improved potency versus linezolid against gram-positive and fastidious gram-negative pathogens. The compounds are also active against linezolid- and ciprofloxacin-resistant Staphylococcus aureus and Enterococcus faecium strains. The MOA for these new antimicrobials is consistent with a combination of protein synthesis and gyrase A/topoisomerase IV inhibition, with a structure-dependent degree of the contribution from each inhibitory mechanism.
- Gordeev, Mikhail F.,Hackbarth, Corinne,Barbachyn, Michael R.,Banitt, Lee S.,Gage, James R.,Luehr, Gary W.,Gomez, Marcela,Trias, Joaquim,Morin, Sara E.,Zurenko, Gary E.,Parker, Christian N.,Evans, Jonathan M.,White, Richard J.,Patel, Dinesh V.
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p. 4213 - 4216
(2007/10/03)
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- An efficient synthesis of ofloxacin and levofloxacin from 3,4- difluoroaniline
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The functionalization at either C-2 or C-3 of N-(tert-butoxycarbonyl)- 3,4-difluoroaniline based on its ortho-deprotonation under different experimental conditions is described. This kind of products can be readily applied to the synthesis of ofloxacin, levofloxacin and related compounds.
- Adrio, Javier,Carretero, Juan C.,Garcia Ruano, Jose L.,Pallares, Antonio,Vicioso, Mercedes
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p. 1563 - 1572
(2007/10/03)
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- Method for the preparation of pyrido benzoxazine derivatives
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There is disclosed a method for the preparation of pyrido benzoxazine derivative having the following formula I, that is improved in both production coat and yield. The method comprises reacting a compound of the following general formula II with tetraalkyl ammonium fluoride or with a mixture of tetraalkyl ammonium halide and metal fluoride in an organic solvent at a reaction temperature of about 30 to about 100° C. for 1 to 3 hours under stirring; and reacting the resulting solution with a metal hydroxide or a metal carboxylate dissolved in water or in a mixture of water and alcohol, for 1 to 3 hours under heat. STR1 wherein X is a fluorine or chlorine atom and X1 and X2 each is a halogen atom or a nitro group, R is an alkyl group containing 1 to 4 carbon atoms and R1, R2, R3 and R4 each is an alkyd group or allyl group containing 1 to 8 carbon atoms.
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- Therapeutic derivatives of diphosphonates
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Novel chemotherapeutic agents having utility in treating infectious diseases such as periodontal disease, certain urinary tract infections, infectious urinary tract stones, and bone cancer, are obtained by combining chemically a diphosphonate compound with a therapeutic agent effective against the foregoing diseases.
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- 7-(1-PYRROLIDINYL)-3-QUINOLONE-AND-NAPHTHYRIDONECARBOXYLIC ACID DERIVATIVES AS ANTIBACTERIAL AGENTS AND FEED ADDITIVES
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7-(1-Pyrrolidinyl)-3-quinolone- and -naphthyridonecarboxylic acid derivatives as antibacterial agents and feed additives, of the formula in which X1 is halogen, X2 is hydrogen, halogen, amino or other radical, R1 is alkyl, cycloalkyl, optionally substituted phenyl or other radical, R2 is hydrogen, alkyl or a dioxolylmethyl radical, R 3 i s A is N, CH, C-halogen, or the like, or forms a bridge with R1, and addition products thereof
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- Synthesis and antibacterial activities of substituted 7-oxo-2,3-dihydro-7h-pyrido[1,2,3-de][1,4]benzoxazine-6-carboxylic acids
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As part of a search for new synthetic antibacterial agents to combat systemic infection, various analogues of 7-oxo-2,3-dihydro-7H-pyrido[1,2,3-de][1,4]benzoxazine-6-carboxylic acids were synthesized. Among the compounds newly synthesized, 9-fluoro-3-methyl-10-(4-methyl-1-piperazinyl)-7-oxo-2,3-dihydro-7H-pyrido[ 1,2,3-de][1,4]benzoxazine-6-carboxylic acid (DL-8280) showed potent antibacterial activity against Gram-positive and -negative pathogens, including Psedomonas aeruginosa, and its metabolic disposition was shown in separate experimentals to be favorable.
- Hayakawa,Hiramitsu,Tanaka
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p. 4907 - 4913
(2007/10/02)
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- Benzoxazine derivatives
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Pyrido[1,2,3-de][1,4]benzoxazine derivatives are described having the formula (I) STR1 wherein X is a halogen atom, R is a hydrogen atom or an alkyl group of 1 to 6 carbon atoms and Z represents mono-substituted, di-substituted or cyclic-substituted amino group which may contain a hetero atom and may have a substituent such as hydroxyl, alkyl having 1 to 6 carbon atoms, amino, hydroxyalkyl having 1 to 6 carbon atoms or mono- or di-alkylamino having 1 to 6 carbon atoms in each alkyl moiety and the pharmaceutically acceptable salt thereof, having antibacterial activity.
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