Marbofloxacin EP Impurity A synthesis

Yield:115551-40-1 95%

Reaction Conditions:

with sodium hydroxide in water at 95; for 6 h;

Steps:

50.A

A suspension of TNOC (10.0 g, 35.43 mmol, 1.0 eq) in an aqueous solution of 5N NaOH (200 mL) was stirred at 95° C. for 6 hours. The mixture was cooled to room temperature and an aqueous solution of 6N HCl was added until precipitation. The precipitate was filtered, washed with water and diethylether and dried to afford the title compound as a white solid (9.1 g, 95%).MS (ESI⁺) (+0.1% HCOOH): 271.0 [C₁₁H₈F₂N₂O₄+H]⁺ (m/z)

References:

US2009/221565,2009,A1 Location in patent:Page/Page column 37