Abstract
By using 6-aminobenzothiazoles as starting meterial, a series of 2-substituted 6-ethyl-6, 9-dihydro-9-oxothiazolo [5, 4-f] quinoline-8-carboxylic acids has been prepared through successive steps of, e.g. condensation with diethyl ethoxymethylenemalonate, Gould-Jacobs reaction, N-alkylation and hydrolysis. These compounds were evaluated for antibacterial activities in vitro. The 2-chloro derivative (10d) showed nearly the same activity with nalidixic acid.
