Sodium Hydroxide → 4-(Cyclopentylamino)-1-ethyl-1H-pyrazolo[3,4-b]pyridine-5-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

A solution of Intermediate 2 (2.2 g) in ethanol: water (95:5, 16.85 ml) was treated with sodium hydroxide (1.2 g) and heated at 50° C. for 16 h. The mixture was concentrated in vacuo and the residue re-dissolved in water (0.85 ml). The solution was acidified to pH4 using acetic acid and the resultant white precipitate was collected by filtration and dried under vacuum to afford Intermediate 3 (1.9 g). LCMS showed MH+=275; TRET=2.65 min

Provenance & Evidence