Hydrochloric Acid → 2,2-Dimethyl-propionic acid 8-(4-acetylamino-benzyl)-3-butyl-2,6-dioxo-1,2,3,6-tetrahydro-purin-7-ylmethyl ester

Participants

Reaction Conditions

Reaction Steps

A mixture of N-[4-(3-butyl-2,6-dioxo-2,3,6,7-tetrahydro-1H-purin-8-ylmethyl)-phenyl]-acetamide (196 mg, 0.55 mmol) in N,N-dimethylformamide (5.0 mL) at 25° C. was treated with sodium carbonate (117 mg, 0.55 mmol) and 2,2-dimethyl-propionic acid chloromethyl ester (0.10 mL, 0.55 mmol). The resulting mixture was warmed to 50° C. for 8 h. At this time, the reaction mixture was poured into a solution of water (2.5 mL) containing a 1N aqueous hydrochloric acid solution (1.65 mL). This solution was extracted with ethyl acetate. The organics were washed with water (1×100 mL) and a saturated aqueous sodium chloride solution (1×100 mL), dried over magnesium sulfate, filtered, and concentrated in vacuo. Flash chromatography (Merck Silica gel 60, 230–400 mesh, 3:2 ethyl acetate/petroleum ether) afforded 2,2-dimethyl-propionic acid 8-(4-acetylamino-benzyl)-3-butyl-2,6-dioxo-1,2,3,6-tetrahydro-purin-7-ylmethyl ester (107 mg, 41.4%) as a yellow foam: FAB-HRMS m/e calcd for C24H31N5O5 (M+H)+ 470.2403, found 470.2408.

Provenance & Evidence