4-{4-[5-(3-tert-Butyl-phenylcarbamoyl)-pyridin-2-yl]-piperazin-1-yl}-benzoic acid ethyl ester → 4-{4-[5-(3-tert-Butyl-phenylcarbamoyl)-pyridin-2-yl]-piperazin-1-yl}-benzoic acid

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Reaction Steps

4-{4-[5-(3-tert-Butyl-phenylcarbamoyl)-pyridin-2-yl]-piperazin-1-yl}-benzoic acid ethyl ester (50 mg, 0.11 mmol) in THF (10 mL) and water (2 mL) was treated with LiOH monohydrate (8.6 mg, 0.22 mmol). After stirring at rt for 4 h the mixture was treated with another portion of LiOH monohydrate (9 mg, 0.22 mmol) and the mixture was stirred at 50° C. for 16 h. The mixture was then cooled and partitioned between EtOAc and water. The acidity of the water layer was adjusted to pH 5 with 1N aqueous HCl. The water layer was extracted twice more with EtOAc and the combined EtOAc layer was dried, filtered and concentrated. The residue was chromatographed on a silica gel column with 0-3% MeOH in CH2Cl2 gradient to afford the product (6 mg; Yield: 13%). HRMS m/z calcd for C27H30N4O3 [M+H]+: 459.2391. Found: 459.2388.

Provenance & Evidence