Methyl [[(methoxycarbonyl)amino](methylthio)methylene]carbamate → 1,1-dimethylethyl 7-(2-{[(methyloxy)carbonyl]amino}-1H-benzimidazol-6-yl)-2,3-dihydro-1,4-benzoxazepine-4(5H)-carboxylate

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Reaction Conditions

Reaction Steps

1,1-Dimethylethyl 7-(4-amino-3-nitrophenyl)-2,3-dihydro-1,4-benzoxazepine-4(5H)-carboxylate (3.3 g, 8.56 mmol) and 10% palladium on carbon (300 mg) were suspended in ethanol (100 mL) and the mixture was hydrogenated at 50 psi using a Parr apparatus for 12 h. The mixture was filtered through a celite pad and the filtrate concentrated. The residue was taken into acetic acid (25 mL) followed by addition of 1,3-bis(methoxycarbonyl)-2-methyl-2-thiopseudourea (2.3 g, 11.15 mmol) and the resulting mixture heated to 80° C. for 30 minutes. The mixture was cooled to room temperature then concentrated and partitioned with ethyl ether (60 mL) and dilute aqueous sodium bicarbonate. The biphasic mixture was allowed to stand for several minutes until a precipitate formed. The solid was collected by filtration, washed with water then ethyl ether and dried to give 1,1-dimethylethyl 7-(2-{[(methyloxy)carbonyl]amino}-1H-benzimidazol-6-yl)-2,3-dihydro-1,4-benzoxazepine-4(5H)-carboxylate (2.98 g, 80% yield) as a white solid. MS (EI) for C23H26N4O5: 439 (MH+).

Provenance & Evidence