5,7-dichlorothiazolo[5,4-d]pyrimidine

5082-82-6

13479-88-4

The general procedure for the synthesis of 5,7-dichlorothiazolo[5,4-d]pyrimidine using thiazolo[5,4-d]pyrimidine-5,7(4H,6H)-dione as starting material was as follows: a 10 mL round bottom flask was charged with intermediate 45.2 (100 mg, 0.59 mmol, 1.00 equiv.), N,N-diisopropylethylamine (DIEA, 0.5 mL) and phosphorus oxychloride (POCl3, 2 mL). The reaction mixture was stirred at 100 °C for 12 hours. After completion of the reaction, the mixture was concentrated under reduced pressure to remove the solvent. The crude product was purified by fast column chromatography to afford intermediate 45.3 (100 mg, 82% yield) as a yellow oil.