Hydrochloric Acid → [3,5-Dimethyl-1-(4-phenylacetyl-benzyl)-1H-pyrazol-4-yl]-acetic acid

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Reaction Conditions

Reaction Steps

Oxidation: {1-[4-(1-Hydroxy-2-phenyl-ethyl)-benzyl]-3,5-dimethyl-1H-pyrazol-4-yl}-acetic acid methyl ester (intermediate 15.1.2, 100 mg, 0.26 mmol) was dissolved in 4 ml dichloromethane, cooled to 0° C. and Dess-Martin periodinane (135 mg, 0.32 mmol) was added to the solution. After warming to room temperature, the mixture was stirred for 3 h. The solvent was evaporated under reduced pressure. Saponification: The ester intermediate (70 mg, 0.19 mmol) was dissolved in 2 ml dioxane and aqueous NaOH solution (0.37 ml, 1 M). After stirring for 2.5 h at 60° C. and dilution with water, aqueous HCl solution (0.39 ml, 1 M) was added. The mixture was extracted with ethyl acetate, and the organic layer was dried with MgSO4 and evaporated under reduced pressure. The residue was purified by preparative reversed phase HPLC (gradient of methanol in water+0.1% NH3).

Provenance & Evidence