214602-25-2Relevant academic research and scientific papers
Synthesis of new quinolone antibiotics utilizing azetidine derivatives obtained from 1-azabicyclo[1.1.0]butane
Ikee, Yoshifumi,Hashimoto, Kana,Kamino, Mai,Nakashima, Masaaki,Hayashi, Kazuhiko,Sano, Shigeki,Shiro, Motoo,Nagao, Yoshimitsu
, p. 346 - 356 (2008/12/22)
A series of 3-sulfenylazetidine derivatives 5a-f were synthesized via the ring-opening reactions of 1-azabicyclo[ 1.1.0]butane (ABB, 3) with thiols 4a-f in 50-92% yields. Treatment of ABB (3) with aromatic amines 9a-e and dibenzylamine (9f) in the presence of Mg(ClO4)2 afforded the corresponding 3-aminoazetidine derivatives 10a-f in 24-65% yields. N-Benzyl-3-bromoazetidine (13), which was obtained by the reaction of ABB (3) with benzyl bromide, gave 3-aliphatic amino-substituted azetidine derivatives 15a, b. Novel fluoroquinolones 7a-f, 11a-f, 16a, b and 25a-c were obtained by the introduction of these azetidine derivatives into the C7 position of a quinolone nucleus 6 and N1-heterocyclic quinolones 21a-c in 21-83% yields. Some of them exhibited a greater antibacterial activity against methicillin-resistant Staphylococcus aureus (MRSA) in comparison with that of clinically used fluoroquinolone, levofloxacin (LVFX).
Synthesis and antibacterial activity of 1-(substituted-benzyl)-6- fluoro,1,4-dihydro-4-oxoquinoline-3-carboxylic acids and their 6,8-difluoro analogs
Sheu,Chen,Fang,Wang,Peng,Tzeng
, p. 955 - 964 (2007/10/03)
Alkylation of 6,7-difluoro-4-hydroxyquinoline-3-carboxylic acid ethyl ester with substituted-benzyl chlorides gave 1-(substituted-benzyl)-6,7- difluoro-1,4-dihydro-4-oxoquinoline-3-carboxylic acid ethyl esters. Their treatment with piperazine or N-methylpiperazine in pyridine yielded 1- (substituted-benzyl)-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)quinoline- 3-carboxylic acid ethyl esters which were hydrolyzed with aqueous sodium hydroxide and then acidified with hydrochloric acid afforded the desired 1- (substituted-benzyl)-6-fluoro-1,4-dihydro-4-oxo-7-(1-piperazinyl)quinoline- 3-carboxylic acids. The 6,8-difluoro analogs were prepared similarly using 6,7,8-trifluoro-4-hydroxyquinoline-3-carboxylic acids. The 6,8-difluoro analogs were prepared similarly using 6,7,8-trifluoro-4-hydroxyquinoline-3- carboxylic acid ethyl ester as a starting material. Some of these quinolones demonstrated fairly good antibacterial activities. Among them, 6-fluoro-1- (4-fluorophenylmethyl)-1,4-dihydro-7-(1-piperazinyl)-4-oxoquinoline-3- carboxylic acid (7d) and 6,8-difluoro-1-(3-fluorophenylmethyl)-1,4-dihydro- 7-(1-piperazinyl)-4-oxoquinoline-3-carboxylic acid (8c) are two of the best.
