Hometert-Butyl 3-bromo-1,4,6,7-tetrahydro-5H-pyrazolo[4,3-c]pyridine-5-carboxylatetert-Butyl 3-bromo-1,4,6,7-tetrahydro-5H-pyrazolo[4,3-c]pyridine-5-carboxylate ≥98%