Sodium Hydroxide → 4-(1-cyclopentyl-4-methoxy-1H-pyrazolo[4,3-c]pyridin-3-yl)thiophene-2-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

To a solution of methyl 4-(1-cyclopentyl-4-methoxy-1H-pyrazolo[4,3-c]pyridin-3-yl)thiophene-2-carboxylate (250 mg) obtained in Step D of Example 12 in methanol (20 mL) was added 1N aqueous sodium hydroxide solution (4 mL) under ice-cooling, and the mixture was stirred at 50° C. for 4 hr. The reaction mixture was concentrated under reduced pressure to evaporate the methanol, and the mixture was partitioned between ethyl acetate and 1N hydrochloric acid (8 mL). The organic layer was washed with saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure to give the title compound (238 mg).

Provenance & Evidence