1-Butanol → 5-(5-acetyl-2-butoxy-3-pyridinyl)-3-ethyl-2-(1-ethyl-3-azetidinyl)-2,6-dihydro-7H-pyrazolo(4,3-d)pyrimidin-7-one

Participants

Reaction Steps

To a stirred suspension of 5-Acetyl-N-[3-(aminocarbonyl)-5-ethyl-1-(1-ethyl-3-azetidinyl)-1H-pyrazol-4-yl]-2-ethoxynicotinamide, the title compound of Preparation 2(e), (1.07 g, 2.5 mMol) in n-butanol (10 mL) under nitrogen atmosphere at room temperature was added n-butyl acetate (7.5 mMol, 0.87 mL) followed by potassium carbonate (7.5 mMol, 1.04 mg) as a single solid portion. The reaction was left to stir at room temperature for 5 minutes before being heated to reflux for 24 hours. The reaction was allowed to cool to room temperature and then reduced to low volume (ca 2 to 3 mL) at reduced pressure. The crude concentrate was then diluted with water (20 mL), this aqueous mixture was then treated with dilute HCl until pH 7 was attained at which point the remaining solvent was azeotroped out under reduced pressure. The resulting precipitate was cooled and filtered and the solid product dried to afford the title compound, 1.09 g, yield by HPLC=81%. M/Z=439 (M+H)+.

Provenance & Evidence