70459-18-6

Upstream product

• 100-44-7 benzyl chloride 
• 70479-46-8 ethyl 1-benzyl-7-chloro-6-fluoro-1,4-dihydro-4-oxoquinoline-3-carboxylate 
• 75073-15-3 ethyl 7-chloro-6-fluoro-4-oxo-1,4-dihydroquinoline 3-carboxylate 
• 214602-13-8 ethyl 1-benzyl-6,7-difluoro-4-oxo-1,4-dihydroquinoline-3-carboxylate 
• 121873-01-6 6,7-difluoro-4-oxo-1,4-dihydroquinoline-3-carboxylic acid ethyl ester 
• 109-01-3 1-methyl-piperazine 
• 214602-53-6 1-Benzyl-6-fluoro-7-(4-methyl-piperazin-1-yl)-4-oxo-1,4-dihydro-quinoline-3-carboxylic acid ethyl ester 
• 70459-17-5 1-benzyl-7-chloro-6-fluoro-4-oxo-1,4-dihydro-quinoline-3-carboxylic acid 

Relevant academic research and scientific papers

Synthesis and antibacterial activity of 1-(substituted-benzyl)-6- fluoro,1,4-dihydro-4-oxoquinoline-3-carboxylic acids and their 6,8-difluoro analogs

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.

SOME REACTIONS OF N-PROPADIENYL-4-QUINOLONES

N-Alkylation of ethyl 6,7,8-trifluoro-1,4-dihydro-4-oxoquinoline-3-carboxylate (Vg) with 3-bromopropyne followed by acidic hydrolysis provided N-propynyl derivative Ic which in alkaline media yielded N-propadienyl derivative IId.Propadienyl derivatives IIa and IIb treated with primary or secondary amines provided intermediates IIIa-IIIc which were hydrolyzed to N-acetonyl derivatives IVa and IVb, respectively.N-Benzylation of ethyl 7-chloro-6-fluoro-1,4-dihydro-4-oxoquinoline-3-carboxylate (Va) followed by hydrolysis yielded 1-benzyl-7-chloro-6-fluoro-1,4-dihydro-4-oxoquinoline-3-carboxylic acid (Vd) which upon a treatment with N-methylpiperazine provided Ve.Compound Ve was hydrogenated on Pd to 6-fluoro-1,4-dihydro-7-(4-methyl-1-piperazinyl)-4-oxoquinoline-3-carboxylic acid (Vf).