Synthesis of the Hydrazinyl Pyridine Intermediate: Phase-Appropriate Delivery

A two-step synthesis of an intermediate for a drug-candidate, 3-fluoro-2-hydrazinyl-5-(1-methyl-1H-pyrazol-4-yl)­pyridine (1), was developed and optimized according to the strategic priorities of the program. The bond disconnection remained unchanged from the initial route to the scale-up routes; however, the process evolved as the program’s priorities progressed. Speed, securing the raw material supply chain, and cost were all factors considered during development. The strategies to enable multikilogram deliveries are highlighted in this report.