INTERMEDIATES AND METHOD OF PREPARING NAPHTHIRIDONE CARBOXYLIC ACID SALTS Russian patent published in 2000 - IPC

FIELD: biologically-active compounds. SUBSTANCE: invention provides naphthiridone carboxylic acid salts having formula I: (I) wherein R'H is pharmaceutically acceptable acid selected from group including R⁴SO₃H, R⁴PO₃H, and YH, R⁴ is C₁-C₆-alkyl and optionally C₁-C₆-alkyl-substituted phenyl or naphthyl, and Y is chlorine atom or nitrate residue. Compounds I are prepared by bringing compound of formula II: (II), wherein R² is (C₁-C₆)-alkyl, aryl-(C₁-C₆)-alkyl, or hydrogen, and P³ is nitro group, into reaction with reduction agent optionally in presence of compound R'H (R' as defined above) and then, if necessary, reaction product is affected by compound R'H, the same or other than that in reduction reaction. Reaction intermediates show antibacterial activity. EFFECT: simplified procedure. 34 cl, 5 ex