To a solution of 6-(4-fluorophenyl)-5-(2-methanesulfonyl-pyrimidin-4-yl)-imidazo[2,1-b]thiazole (L) (1.05 g, 2.8 mmol) in dimethylsulfoxide (12.0 mL) is added 4-amino-piperidine-1-carboxylic acid tert-butyl ester (1.12 g, 5.6 mmol) followed by Hunig's Base (0.76 mL, 5.6 mmol). The reaction mixture is sealed and set to shake at 100° C. for 12 hours. After cooling to room temperature, water is added (50 mL) and the aqueous phase extracted with ethyl acetate (4×20 mL). The combined organic phase is washed with a saturated, aqueous, sodium chloride solution (3×50 mL) and dried over anhydrous sodium sulfate. The organic phase is filtered and the solvent evaporated in vacuo. The crude product is purified by silica gel column chromatography eluting with ethyl acetate/hexane (3/2). The compound 4-{4-[6-(4-fluorophenyl)-imidazo[2,1-b]thiazol-5-yl]-pyrimidin-2-ylamino}-piperidine-1-carboxylic acid tert-butyl ester (M) (Compound CCXXXIII, Table 2) is obtained as a light yellow solid (1.2 g, 88%); m.p. 209-211° C.;
