Pyridine → HCID 57393827, compound

Participants

Reaction Steps

Trifluoroacetic acid anhydride (257 uL, 1.83 mmol) was added slowly to a cooled suspension of 2-methoxy-4-(4-phenyl-4,5,6,7-tetrahydro-benzothiazol-2-ylamino)-benzamide (625 mg, 1.65 mmol) in dioxane (2 mL) and pyridine (292 uL, 3.6 mmol). The white suspension was stirred for 30 minutes under cooling and then for 2 hours at 50° C. and for 3 hours at 80° C. Additional trifluoroacetic acid anhydride (300 uL), pyridine (400 uL) and dioxane (5 mL) were added and the reaction was stirred at 80° C. for 2 hours resulting in a clear brown solution. The solvent was removed under reduced pressure and the residue was partitioned between ethyl acetate and water. The organic layer was washed twice with saturated aqueous sodium hydrogen carbonate, brine, dried over magnesium sulfate, filtered and the solvent was removed under reduced pressure. The residue was purified on silica gel using dichloromethane with 4% methanol as eluent to yield the title compound (236 mg, 40%) as a beige foam. MS ISP (m/e): 362.3 (100) [(M+H)+].

Provenance & Evidence