| 摘要 |
<p>NEW MATERIAL:A compound expressed by formula I [R1 represents (substituted) lower alkyl, (substituted) phenyl, etc.; R2 represents H or carboxy-protecting group; R3 represents H, halogen or (substituted) amino; R4 represents halogen; R5 represents H, halogen lower alkyl, etc.; Y represents (substituted) 3- oxaxolidinyl, etc.]. EXAMPLE:Ethyl 1-cyclopropyl-6-fluoro-7-(3-oxazolidinyl)-1,4-dihydro-4- oxoquinoline-3-carboxylate. USE:An antibacterial agent against Gram-negative and Gram-positive bacteria, which is not only useful for human, animals, etc., but also useful as medicines for fish diseases, agricultural chemicals and food preservatives. PREPARATION:A quinolone derivative expressed by formula II (X represents reactive leaving group) is condensed with an alkanolamine derivative expressed by formula III [R6 represents (substituted) ethylene, etc.] to form a compound expressed by formula IV, which is then reacted with a dialkoxymethane derivative expressed by formula V (R7 represents H, etc.; R8 represents lower alkyl).</p> |
