Development of a Practical and Scalable Synthesis of a Potent CRTH2 Antagonist

Abstract

This contribution describes the process research and development of a practical and scalable synthetic method towards compound 1, which has a potent CRTH2 antagonistic activity. The medicinal chemistry synthetic route and second generation synthetic route had several issues in scale-up synthesis. In contrast, the synthetic method described here does not require purification by column chromatography for all steps, and the formation of impurities is suppressed well. This highly efficient and scalable process was successfully demonstrated in the large-scale synthesis of 1.