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

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)+.

1. temperatureto cool
2. customThe resulting mixture was evaporated under reduced pressure
3. customthe residue partitioned between water (5 ml) and dichloromethane (5 ml)
4. customThe phases were separated
5. extractionthe aqueous layer extracted with dichloromethane (2×10 ml)
6. dry with materialthe combined organic solutions dried (MgSO4)
7. customevaporated under reduced pressure
8. customThe residual yellow solid was purified by column chromatography on silica gel

ORD record

ord-df7e3bdbee0a4a36b3e544d4633b48d0

Source dataset

uspto-grants-2002_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US06458951B2