反应详情

Tert-butyl 4-{1-[(1-ethyl-1H-pyrazol-4-yl)methyl]-2,4-dioxo-6-phenyl-1,4-dihydrothieno[3,2-d]pyrimidin-3(2H)-yl}piperidine-1-carboxylate (763 mg; compound B18) is dissolved in a solution of hydrogen chloride in 1,4-dioxane (10 ml, 4.0 M). The solution is stirred for 1 h at RT. The resulting precipitate is filtered off, washed with diethyl ether and dried to give the crude title compound. To remove impurities the free base is submitted to flash column chromatography (silica gel, eluent: MeOH). The purified free base of the title compound is taken up in diethyl ether and the solution is treated with chlorotrimethylsilane. The resulting precipitate is filtered off and dried to afford the title compound as a solid.

1. filtrationThe resulting precipitate is filtered off
2. washwashed with diethyl ether
3. customdried
4. customto give the crude title compound
5. customTo remove impurities the free base
6. additionthe solution is treated with chlorotrimethylsilane
7. filtrationThe resulting precipitate is filtered off
8. customdried