Propyl mercaptan → 3-Ethyl-5-[5-(4-ethylpiperazin-1-ylsulphonyl]-2-methoxypyridin-3-yl]-2-(pyridin-2-yl)methyl-2,6-dihydro-7H-pyrazolo[4,3-d]pyrimidin-7-one

Participants

Reaction Conditions

Reaction Steps

A stirred mixture of the title compound of Example 1 (350 mg, 0.63 mmol), potassium bis(trimethylsilyl)amide (630 mg, 3.15 mmol) and n-propanethiol (5 ml) was heated in a sealed vessel at 110° C. for 48 hours, then allowed to cool and evaporated under reduced pressure, The residue was azeotroped with dichloromethane:methanol (95:5), then partitioned between water (10 ml) and dichloromethane (15 ml). The phases were separated, the aqueous phase extracted with dichloromethane (2×15 ml) and the combined organic solutions dried (MgSO4) and evaporated under reduced pressure. This residue was purified by column chromatography on silica gel, using dichloromethane:methanol (97:3) as eluant, to yield the title compound (170 mg, 50%) as a yellow is solid. Found: C, 54.50; H, 5.64; N, 19.93. C25H30N8O4S; 0.75H2O requires C, 54.38; H, 5.75; N, 20.29%. δ (CDCl3): 1.02 (3H, t), 1.32 (3H, t,) 2.40 (2H, q), 2.55 (4H, m), 3.06 (2H, q), 3.14 (4H, m), 4.26 (3H, s), 5.68 (2H, s), 7.14 (1H, d), 7.22 (1H, m), 7.64 (1H, m), 8.58 (1H, d), 8.66 (1H, s), 9.05 (1H, s), 10.59 (1H, s). LRMS: m/z 540 (M+2)+.

Provenance & Evidence