(S)-tert-butyl (1-(5-((6-(3-chloro-5-fluoro-4-hydroxyphenyl)-3-(cyclobutanecarbonyl)-1,5-naphthyridin-4-yl)amino)pyridin-2-yl)piperidin-3-yl)carbamate 、
三氟乙酸 、 以to afford the desired product (94 mg, 72% over two steps) as a orange-brown solid的产率得到(S)-(4-{[6-(3-aminopiperidin-1-yl)pyridin-3-yl]amino}-6-(3-chloro-5-fluoro-4-hydroxyphenyl)-1,5-naphthyridin-3-yl)(cyclobutyl)methanone trihydrochloride