Hydrochloric Acid → 5-(6-Bromo-2-phenyl-imidazo[1,2-a]pyridin-7-ylcarbamoyl)-1-methyl-1H-pyrazole-4-carboxylic acid

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Reaction Steps

NaOH (3N, 0.65 ml) was added to a solution of 5-(6-bromo-2-phenyl-imidazo[1,2-a]pyridin-7-ylcarbamoyl)-1-methyl-1H-pyrazole-4-carboxylic acid ethyl ester (460 mg, 0.98 mmol) in a mixture of THF (5 ml) and methanol (5 ml), and the reaction mixture was stirred at r.t. overnight. An additional amount of NaOH (3N, 0.65 ml) and water (2 ml) were added and the mixture was heated to reflux (1 h). After cooling to r.t., HCl (conc., ˜0.7 ml) was added to the cooled mixture, and the brown suspension was stirred at r.t. (15 min). The suspension was then filtered, and the precipitated title compound (150 mg, 35%) was washed with a small amount of water, dried under vacuum, and used in the next step without further purification. MS (m/e)=440.3 [M+H+].

Provenance & Evidence