Methyl chloroformate → Methyl {(1R)-1-(4-methyl-1-oxo-1,3-dihydro-2-benzofuran-5-yl)-2-[2-(4-methyl-5-oxo-2,5-dihydrofuran-3-yl)-1-oxo-2,8-diazaspiro[4.5]dec-8-yl]ethyl}carbamate

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Reaction Steps

To a solution of (R)-8-(2-amino-2-(4-methyl-1-oxo-1,3-dihydroisobenzofuran-5-yl)ethyl)-2-(4-methyl-5-oxo-2,5-dihydrofuran-3-yl)-2,8-diazaspiro[4.5]decan-1-one (Example 62) (35 mg, 0.08 mmol) and triethylamine (17 μL, 0.12 mmol) in dichloromethane (2 mL) was added methyl chloroformate (11 mg, 0.12 mmol) at 0° C. under nitrogen atmosphere. The reaction mixture was allowed to warm to room temperature and stir for 2 h. TLC indicated half of starting material remained. The reaction mixture was re-cooled to 0° C. and triethylamine (17 μL, 0.12 mmol) was added thereto, followed by methyl chloroformate (11 mg, 0.12 mmol). The reaction mixture was allowed to warm to room temperature and stirred for another 2 h. TLC showed the reaction was complete. The resulting mixture was concentrated in vacuo. The residue was taken up into small amount of DCM and purified by preparative TLC (dichloromethane: methanol=15:1) to afford the title compound. MS-ESI (m/z): 498 (M+1)+.

Provenance & Evidence