Trifluoroacetic acid was added (10 mL) to the crude 3-(4-imidazol-1-ylmethylphenyl)-5-butyl-N-tert-butylthiophene-2-sulfonamide from step (c) above, and one drop (ca. 0.05 mL) of anisol was added to the mixture. The reaction mixture was stirred under N2 atmosphere for 30 hours and then evaporated and co-evaporated with acetonitrile. The crude product was purified by column chromatography (CH2Cl2:MeOH (20:1)) to give sub-title compound (232 mg, 0.62 mmol) in 49% yield (from 1-(4-bromobenzyl)-1H-imidazole).
