4-methyl-2-[(R)-3-(4-propyl-benzylcarbamoyl)-piperazin-1-yl]-thiazole-5-carboxylic acid tert-butyl ester → 2-[(R)-4-(2-fluoro-4-trifluoromethoxy-benzenesulfonyl)-3-(4-propyl-benzylcarbamoyl)-piperazin-1-yl]-4-methyl-thiazole-5-carboxylic acid tert-butyl ester

Participants

Reaction Steps

To a solution of the compound (50 mg) obtained in Step 6 in pyridine (0.5 ml) was added, with stirring at room temperature, 2-fluoro-4-trifluoromethoxybenzenesulfonyl chloride (46 mg). After stirring overnight at room temperature, the reaction mixture was concentrated under reduced pressure. The residue was partitioned by adding ethyl acetate and water. The organic layer was washed successively with 1N aqueous hydrochloric acid solution, saturated aqueous sodium hydrogen carbonate solution and saturated brine, dried over anhydrous magnesium sulfate, filtrated, and concentrated under reduced pressure. The residue was purified by thin layer chromatography (ethyl acetate:n-hexane=1:2) to give the title compound (59 mg).

Provenance & Evidence