Hydrochloric Acid → HCID 178470318, compound

Participants

Reaction Conditions

Reaction Steps

To a solution of ethyl 2-{[5-(benzyloxy)-N-(tert-butoxycarbonyl)-L-norvalyl]amino}-3-oxobutanoate (5.31 g, 11.8 mmol) in ethanol (20 mL) was added 4N hydrochloric acid in 1,4-dioxane (20 mL) at room temperature. After being stirred for 16 h at same temperature, the reaction mixture was concentrated in vacuo. A solution of the residue in pyridine (40 mL) was heated at 60° C. for 23 h. After being cooled to ambient temperature, the mixture was concentrated in vacuo. The residue was poured into water, and the mixture was extracted with chloroform. The organic layer was washed with water and saturated brine, dried over sodium sulfate, filtrated and concentrated in vacuo. To a solution of the residue in dichloromethane (20 mL) was added manganes dioxide (1.03 g) at room temperature. After being stirred for 1.5 h at same temperature, the reaction mixture was filtrated through celite with chloroform. The filtrate was combined and concentrated in vacuo. The crude was purified by silica gel column chromatography (chloroform to chloroform:methanol=19:1) to give ethyl 5-[3-(benzyloxy)propyl]-6-hydroxy-3-methylpyrazine-2-carboxylate. MS (APCI): m/z 331 (M+H).

Provenance & Evidence