1,3-Propanediamine, N'-(ethylcarbonimidoyl)-N,N-dimethyl-, monohydrochloride → [(1S)-2-(3,5-Dichloro-1-oxido-pyridin-1-ium-4-yl)-1-(3,4-dimethoxyphenyl)ethyl] 3-[(2-tert-butoxy-2-oxo-1-phenyl-ethyl)sulfamoyl]benzoate

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Reaction Steps

3-[(2-tert-Butoxy-2-oxo-1-phenyl-ethyl)sulfamoyl]benzoic acid (1.216 g, 3.11 mmol) was added to a stirred suspension of (S)-3,5-dichloro-4-(2-(3,4-dimethoxyphenyl)-2-hydroxyethyl)pyridine 1-oxide (1.07 g, 3.11 mmol) in N,N-dimethylformamide (12 mL). To the resultant solution was added N,N-4-(dimethylamino)pyridine (0.189 g, 1.55 mmol) followed by N-(3-dimethylaminopropyl)-N′-ethylcarbodiimide hydrochloride (1.192 g, 6.22 mmol) and the reaction was stirred at room temperature for 18 hours. After this time, the reaction mixture was concentrated under reduced pressure and water (30 mL) was added; the resulting off-white precipitate was filtered and dried in air. The crude material was purified over a 50 g silica cartridge on an ISOLERA system; eluting initially with iso-hexane with an increasing solvent gradient to 100% ethyl acetate over four column volumes, after which 100% ethyl acetate was maintained for six column volumes. The desired fractions were combined and concentrated under reduced pressure to yield the title product as a white solid (1.340 g, 60%).

Provenance & Evidence