Figure 7 |. Key transformations along the synthetic routes to selected compounds.

A | One synthetic route to NITD609, a potent nMoA antimalarial, involved an enantioselective aza-Diels–Alder reaction between indole 46 and ketimine 47 to afford spirocycle 48, which is one step from NITD609. B | The synthesis of antimalarial BRD7929 contained two key cyclizations. First, treatment of chloride 50 with strong base supplied azetidine 51. Subsequent functionalization furnished RCM substrate 52, which was cyclized to diazocine 53 en route to BRD7929. C | From aniline 54, imine 55 was an ideal substrate for a diastereo- and enantioselective Povarov reaction. The resulting tetrahydroquinoline 56 was readily converted to BRD0761, which shows nMoA activity against C. difficile. D | Similar to BRD7929, the tuberculosis probe BRD4592 was accessed via a chiral azetidine (59), which in turn was generated from chloride 58 and amino alcohol 57.