Synthesis of the Quinolone ABT-492: Crystallizations for Optimal Processing

Abstract

ABT-492 has been under development at Abbott Laboratories as a quinolone antibiotic. A convergent syntheses was utilized to prepare the compound on a multi-kilogram scale. Difficulties in isolation of intermediates were overcome by developing control of the physical forms. Examples of controlling the agglomeration, crystal habit, and polymorphism of intermediates and the API are described.