Studies on antibacterial agents. III. Synthesis and antibacterial activities of substituted 1,4-dihydro-8-methyl-4-oxoquinoline-3-carboxylic acids.

Abstract
A series of substituted 4-oxoquinoline-3-carboxylic acids having a methyl group at the 8-position was prepared and tested for their antibacterial activity. 7-(trans-3-Amino-4-methyl-1-pyrrolidinyl)-1-cyclopropyl-1,4-dihydro-6-fluroro-8-methyl-4-oxoquinoline-3-carboxylic acid (21) exhibited highly potent antibacterial activity against both gram-positive and gram-negative bacteria, including Pseudomonas aeruginosa.