Question

Which generation of quinolones are broad spectrum?

		First
		Second
		Third

Answer 1

Which generation of quinolones are broad spectrum?

Third generation quinolones has a broad spectrum activity on both gram negative and gram positive group of bacterias.egs.levofloxacin.Synthesis of fleroxacin paved the way of quinolones to enter into third generation. The improvements were the addition of alkylated piperazine and pyrrolidinyl groups to the R7 position, and –NH2, –OH, and –CH3 groups to the R5 position to the pharmacophore. The third generation added new substituent  chloro group (Cl) at the R8 position,this improved the anti-Gram-positive activity of the drug.

First generation quinolones group (e.g.., nalidixic acid) achieved minimum serum levels and effective against gram negative bacterias .They are used to treat only gram negative agents with short half life.

Second generation quinolones group(e.g.., ciprofloxacin) has increased gram negative activity.It has got increased half life compared with first generation quinolones.