NEW MATERIAL:A compound expressed by formula I {X1 and X2 are halogen; R1 is formula II [R5 and R6 are H or lower alkyl; Y is O, S, R10-N (R10 is same as R5 or R6)] or formula III (R7 is H, OH, amino, etc.; R8 and R9 are same as R5 or R6; n is 3W5); R2 and R3 are R5, R6, cycloalkyl, (substituted) phenyl, etc.; R4 is lower alkyl, lower alkenyl, (substituted) phenyl, etc.}, ester and salt thereof.
EXAMPLE: 5-Amino-1-cyclopropyl-6, 8-difluoro-7-(3,4-dimethyl-1-piperazinyl)-1,4-di hydro-4-oxoquinoline-3-carboxylic acid.
USE: A medicine and antimicrobial agent used as a madicine for human bodies and animals or drug for fish diseases, agricultural chemical, preservative for food, etc.
PREPARATION: For example, a novel carboxylic acid ester expressed by formula IV (X is X1 or X2) or ester thereof is reacted with a compound expressed by the formula R1-H in an inert solvent, as necessary, in the presence of an acid acceptor to afford the aimed compound expressed by formula I.
MIYAMOTO KOSHI
EGAWA HIROSHI
NAKAMURA SHINICHI
