Phosphorus oxychloride → tert-butyl N-[(1S)-2-[[(3S)-5-[(6-bromo-2-methoxy-1-naphthyl)methyl]-1-[5-[(3S)-5-[(6-bromo-2-methoxy-1-naphthyl)methyl]-3-[[(2S)-2-[tert-butoxycarbonyl(methyl)amino]propanoyl]amino]-4-oxo-2,3-dihydro-1,5-benzodiazepine-1-carbonyl]pyrazine-2-carbonyl]-4-oxo-2,3-dihydro-1,5-benzodiazepin-3-yl]amino]-1-methyl-2-oxo-ethyl]-N-methyl-carbamate

Participants

Reaction Steps

To a solution of {(S)-1-[(S)-1-(6-bromo-2-methoxy-naphthalen-1-ylmethyl)-2-oxo-2,3,4,5-tetrahydro-1H-benzo[b][1,4]diazepin-3-ylcarbamoyl]-ethyl}-methyl-carbamic acid tert-butyl ester (Intermediate 11) (300 mg, 0.49 mmol) and pyrazine-2,5-dicarboxylic acid (41.2 mg, 0.24 mmol) in pyridine (5 mL) at 0° C. was added POCl3 (46 μL, 0.49 mmol) and the cooling bath removed. After 5 h, the mixture was diluted with dichloromethane, washed with water, dried (Na2SO4) and concentrated. The residue was purified by preparative reverse phase HPLC to afford tert-butyl N-[(1S)-2-[[(3S)-5-[(6-bromo-2-methoxy-1-naphthyl)methyl]-1-[5-[(3S)-5-[(6-bromo-2-methoxy-1-naphthyl)methyl]-3-[[(2S)-2-[tert-butoxycarbonyl(methyl)amino]propanoyl]amino]-4-oxo-2,3-dihydro-1,5-benzodiazepine-1-carbonyl]pyrazine-2-carbonyl]-4-oxo-2,3-dihydro-1,5-benzodiazepin-3-yl]amino]-1-methyl-2-oxo-ethyl]-N-methyl-carbamate (52 mg, 7.82%) as an off white solid. LC-MS: 1355.0 (M+H).

Provenance & Evidence