Patent attributes
This invention relates to a macrolide composition, more particularly an amorphous form (Form-III) of 3R, 4S, 5S, 6R, 7R, 9R, 11S, 12R, 13S, 14R-6-[(2S,3R,4S,6R)-4-dimethylamino-3-hydroxy-6-methyloxan-2-yl]oxy-14-ethyl-7,12,13-trihydroxy-4-[(2R,4R,5S,6S)-5-hydroxy-4-methoxy-4,6-dimethyloxan-2-yl]oxy-10-(2-methoxyethoxymethoxyimino)-3,5,7,9,11,13-hexamethyl-1-oxacyclotetradecan-2-one or roxithromycin characterized by the absence of peaks in the infra-red spectrum of amorphous (Form-I11) of roxithromycin at 3577.15; 3526.03; 3465.27 and 3276.24 cm-1 relative to the infra-red spectrum of the prior art roxithromycin raw material displaying peaks at 3577.15; 3526.03; 3465.27 and 3276.24 cm-1 and further characterized by an increased solubility of at least 50% over prior art anhydrous and monohydrated roxithromycin in acetate buffer (pH 4.5), phosphate buffer (pH 6.8) and water.
