| 摘要 |
<p>NEW MATERIAL:A compound of formula I (R1 is H or protecting group; R2 is alkenyl, alkyl, etc.), and a salt thereof. EXAMPLE:1-Ethyl-6-fluoro-1,4-dihydro-4-oxo-7-( 1-piperazinyl )-1,8-naphthyridine- 3-carboxylic acid. USE:An antimicrobial agent and a synthetic intermediate therefor having improved effects on urinary tract infection, ascending renal infection and systemic infection even in a small dose with very low toxicity. PROCESS:A compound of formula II (R3 is H or alkyl) is oxidized with a hypohalogenate or silver oxide, or reacted with an iodine-pyridine mixture and then treated with an alkali to give the compound of formula I.</p> |
