METHOD FOR MAKING QUINOLONE CARBOXYLIC ACIDS OR NAPHTHYRIDINE CARBOXYLIC ACIDS IN FREE BASE FORM

摘要

The present invention provides a method of making quinolone carboxylic acids or naphthyridine carboxylic acids in free base form, the method comprising dissolving a quinolone carboxylic acid salt or naphthyridine carboxylic acid salt in a solvent system to form a solution; combining the solution containing the quinolone carboxylic acid salt or naphthyridine carboxylic acid salt with a calcium salt in an amount in the range of about 0.01% to about 5.0% by weight of the quinolone carboxylic acid salt or naphthyridine carboxylic acid salt and a base, the combination resulting in the formation of a precipitate; and collecting the precipitate. Also provided is a solid bulk pharmaceutical chemical composition which is the product resulting from the precipitation.