反应详情

A solution of lithium hydroxide monohydrate (16.8 mg, 0.38 mmol) in water (0.5 mL) was added to a solution of 4-oxo-hexahydro-pyrrolo[1,2-a]pyrazine-2,6-dicarboxylic acid 6-ethyl ester 2-methyl ester (86 mg, 0.32 mmol) in methanol (1 mL) and tetrahydrofuran (1 mL). After 2 hours, an aqueous solution of hydrogen chloride (1N, 0.41 mL, 0.41 mmol) was added and the organic solvents were removed under reduced pressure. The resulting aqueous solution was lyophilized for 16 hours to give 4-oxo-hexahydro-pyrrolo[1,2-a]pyrazine-2,6-dicarboxylic acid 2-methyl ester. A yield of 100% was assumed for the subsequent step. C10H14N2O5 calculated 242.1, observed [M+1]+ 242.9, [M+1]− 241.1; rt=1.54 min.

1. customthe organic solvents were removed under reduced pressure
2. waitThe resulting aqueous solution was lyophilized for 16 hours