To a stirred suspension of 500 mg (2.31 mmol) 2-amino-4-chloro-6-methanesulfinyl-pyrimidine-5-carbonitrile in 10 ml DME were added 482 mg (3.46 mmol) 2-mercapto-ethylpyridine and 0.88 ml (5.77 mmol) DBU and stirring continued for 1 hour at room temperature. 50 ml water was then added and the resulting crystals collected by filtration and washed with ethyl acetate to afford 300 mg (33%) 2-amino-4,6-bis-(2-pyridin-2-yl-ethylsulfanyl)-pyrimidine-5-carbonitrile as a white crystalline solid. ES-MS m/e (%): 395 (M+H+, 100).
