1-Butanol → 5-[2-n-Butoxy-5-(4-ethylpiperazin-1-ylsulphonyl)pyridin-3-yl]-3-ethyl-2-(pyridin-2-yl)methyl-2,6-dihydro-7h-pyrazolo[4,3-d]pyrimidin-7-one

Participants

Reaction Conditions

Reaction Steps

A mixture of the title compound of Example 1 (200 mg, 0.36 mmol), potassium bis(trimethylsilyl)amide (360 mg, 1.81 mmol) and n-butanol (5 ml) was stirred at 100° C. for 18 hours, then allowed to cool. The resulting mixture was evaporated under reduced pressure and the residue partitioned between water (5 ml) and dichloromethane (5 ml). The phases were separated and the aqueous layer extracted with dichloromethane (2×10 ml), then the combined organic solutions dried (MgSO4) and evaporated under reduced pressure. The residual yellow solid was purified by column chromatography on silica gel, using dichloromethane: methanol (97.5:2.5) as eluant, to yield the title compound (145 mg, 69%) as a white solid. Found: C, 57.43; H, 6.29; N. 18.82. C28H36N8O4S; 0.20 H2O requires C, 57.56; H, 6.28; N, 19.18%. δ (CDCl3): 1.03 (6H, 2×t), 1.30 (3H, t), 1.55 (2H, m), 1.94 (2H, m), 2.40 (2H, q), 2.55 (4H, m), 3.03 (2H, q), 3.13 (4H, m), 4.67 (2H, t), 5.68 (2H, s), 7.10 (1H, d), 7.22 (1H, m), 7.62 (1H, m), 8.56 (1H, d), 8.62 (1H, s), 9.01 (1H, s), 10.64 (1H, s). LRMS: m/z 581 (M+1)+.

Provenance & Evidence