1979-97-1

1979-98-2

1979-97-1

Example 99; 4-Hydroxy-4-[3-(trifluoromethyl)phenyl]piperidine-1-carboxylic acid (7-methoxy-5-methylthio-thiazolo[5,4-d]pyrimidin-2-yl)-amide; Step 1: 4,6-dihydroxy-2-methylthio-pyrimidine (10.0 g, 63.22 mmol) was slowly added to fuming nitric acid (30 mL) at 0 °C, the addition process lasted for 1 hour. The reaction mixture was continued to be stirred at 0 °C for 1 h to form a red solution. Subsequently, the reaction solution was poured into ice water and a light brown solid precipitated. The solid was collected by filtration and washed sequentially with water and ether. The resulting solid was dried under vacuum to afford 4,6-dihydroxy-2-methylthio-5-nitropyrimidine (9.30 g, 72% yield) as a light brown solid.LRMS (M+H)+ m/z: 203 (C5H5N3O4S calculated value). The results of nuclear magnetic resonance (NMR) spectral analysis were consistent with the structure of the target compound.