BIOLOGICAL-ACTIVITY OF NEW AZA ANALOGS OF QUINOLONES

A series of novel derivatives of 4H-pyrido[1,2-a]pyrimidine, 1,4-dihyd ro-4-oxo-1,5-naphthyridine and 1,4-dihydro-4-oxo-1,6-naphthyridine wer e prepared and their biological activity was compared with that of nal idixic acid. The in vine antibacterial activity of the tested compound s was lower than that of nalidixic acid except for two agents, 1b and 2c, with a higher activity against Enterococcus faecalis. The compound s were tested for their ability to cure four plasmids from two species of Enterobacteriaceae. The derivatives eliminated three plasmids (pKM 101, pBR322, F'lac) at one-half or one-quarter of the minimal inhibito ry concentration. Plasmid RP4 was unaffected by the treatment. None of these compounds showed better antichloroplast activity than nalidixic acid.