With the exclusion of moisture, 261 mg (1.00 mmol) of 3-amino-4-(3-chlorophenylamino)-1H-pyrazolo[3,4-d]pyrimidine (see Step 1.6) are dissolved in 2.5 ml of dioxane and 1 ml of DMEU; 202 mg (1.1 mmol) of 4-chloro-2-methyl-phenyl isothiocyanate (Maybridge) are added and the reaction mixture is stirred overnight at RT and finally for 16 hours at 60° C. Working-up analogously to Example 66 and stirring in DMSO/ethyl acetate yield 3-[(4-chloro-2-methyl-phenyl-amino)-thiocarbonyl-amino]-4-(3-chloro-phenylamino)-1H-pyrazolo[3,4-d]pyrimidine; HPLC: tRet(grad20-100)=12.2; FAB-MS: (M+H)+=444.
