| abstract |
NEW MATERIAL:A compound (salt) of formula I [R is (substituted)cyclic amino]. EXAMPLE:9-Fluoro-3-methylene-10-( 4-methyl-1-piperazinyl )-7-oxo-2,3-dihydro-7H- pyrido[1,2,3-de][1,4]benzoxazine-6-carboxylic acid. USE:An antimicrobial agent effective against Gram-negative and Gram-positive bacterial including Pseudomonas aeruginosa. PROCESS:An alkyl 9,10-Difluoro-3-methylene-7-oxo-2,3-dihydro-7H-pyrido[1,2,3-de] [1,4]benzoxazine-6-carboxylate of formula II (R1 is alkyl) is reacted with an amine of the formula R-H, e.g. N-methylpiperazine, to carry out the substitution reaction of the amine with the fluorine atom at the 10-position, and the reaction product ester is then hydrolyzed to give the aimed compound of formula I . Alternatively, the compound of formula II may be first hydrolyzed and then reacted with the amine. |