Development of a Scalable Synthesis of an Azaindolyl-Pyrimidine Inhibitor of Influenza Virus Replication

A scalable, asymmetric route for the synthesis of the influenza virus replication inhibitor 2 is presented. The key steps include an enzymatic desymmetrization of cis-1,3-cyclohexanediester in 99% yield and 96% ee, SNAr displacement of a methanesulfinylpyrimidine, and a Curtius rearrangement to form a morpholinyl urea. This high-yielding route allowed us to rapidly synthesize hundreds of grams of 2 in 99% purity to support in vivo studies.