1979-96-0

4,6-Dichloro-2-(methylthio)-5-nitro-pyrimidine is a useful synthetic intermediate. It is used to prepare Cathepsin K inhibition SAR. It is also used to synthesize GS39783 (G797150) which is an allosteric positive modulator of GABAB receptors.

Step 2: 4,6-Dihydroxy-2-methylthio-5-nitropyrimidine (9.30 g, 45.81 mmol) was mixed with phosphorus trichloride (40 mL) and diethylaniline (12 mL) and the reaction was carried out at reflux for 1 hour. Upon completion of the reaction, the reaction mixture was partially evaporated, followed by slow pouring of the remaining liquid into ice water to precipitate a brown solid. The solid product was collected by filtration and washed well with cold water. The resulting solid was dried under vacuum to afford 4,6-dichloro-2-methylthio-5-nitropyrimidine (10.5 g, 95% yield) as a brown solid. Low resolution mass spectra (LRMS) of the product showed m/z = 240 (corresponding to the [M + H]+ ion of C5H3Cl2N3O2S). Nuclear magnetic resonance (NMR) spectral analysis showed results consistent with the structure of the target compound.

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