Sodium Thiosulfate → (3S)-3-({[8-(cyclohexylmethoxy)-2-methylimidazo[1,2-a]pyridin-3-yl]carbonyl}amino)-3-(2-fluorophenyl)propanoic acid

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Reaction Steps

To a solution of 290 mg of 8-(cyclohexylmethoxy)-N-[(1S)-1-(2-fluorophenyl)-3-hydroxypropyl]-2-methylimidazo[1,2-a]pyridine-3-carboxamide in dichloromethane was added 300 mg of 1,1,1-triacetoxy-1,1-dihydro-1,2-benziodoxol-3(1H)-one, followed by stirring overnight. To the reaction mixture were added saturated aqueous sodium bicarbonate, an aqueous sodium thiosulfate solution, and ethyl acetate to carry out a layer separation operation. The organic layer was washed with saturated aqueous sodium bicarbonate and dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. To a solution of the obtained residue and 230 μl of 2-methyl-2-butene in 6.5 ml of dioxane was added 1.7 ml of an aqueous solution of 93 mg of sodium chlorite and 315 mg of sodium dihydrogen phosphate in a water bath, followed by stirring for 30 minutes in a water bath. To the reaction mixture were added water, 1 M hydrochloric acid, and chloroform to carry out a layer separation operation. The organic layer was dried over anhydrous magnesium sulfate, the solvent was evaporated under reduced pressure, and the obtained residue was purified by silica gel column chromatography. To the obtained purified product was added diisopropyl ether, and the resulting solid was filtered and dried to obtain 80 mg of (3S)-3-({[8-(cyclohexylmethoxy)-2-methylimidazo[1,2-a]pyridin-3-yl]carbonyl}amino)-3-(2-fluorophenyl)propanoic acid.

Provenance & Evidence