4-(4-{5-[2-(5-Chloro-2-fluoro-phenyl)-[1,8]naphthyridin-4-yl]-pyridin-3-yl}-pyrazol-1-yl)-piperidine-1-carboxylic acid tert-butyl ester → 2-(5-chloro-2-fluoro-phenyl)-4-[5-(1-piperidin-4-yl-1H-pyrazol-4-yl)-pyridin-3-yl]-[1,8]naphthyridine dihydrochloride

Participants

Reaction Steps

A slurry of 155 mg (0.265 mmol) 4-(4-{5-[2-(5-chloro-2-fluoro-phenyl)-[1,8]naphthyridin-4-yl]-pyridin-3-yl}-pyrazol-1-yl)-piperidine-1-carboxylic acid tert-butyl-ester in 1.5 ml 4 N HCl in dioxane was treated with 1 drop of methanol. The solution thus formed was left for 3 hours at room temperature and subsequently evaporated. The residue was treated with tert-butyl-methyl-ether and the solid was filtered off. The residue was dissolved in water and lyophilized yielding 2-(5-chloro-2-fluoro-phenyl)-4-[5-(1-piperidin-4-yl-1H-pyrazol-4-yl)-pyridin-3-yl]-[1,8]naphthyridine dihydrochloride als colourless lyophilisate; HPLC-MS: 1.65 min, [M+H] 485.

Provenance & Evidence