Water → 2,2-Dimethyl-propionic acid 8-(4-acetylamino-benzyl)-3-butyl-1-[2-(tert-butyl-dimethyl-silanyloxy)-benzyl]-2,6-dioxo-1,2,3,6-tetrahydro-purin-7-ylmethyl ester

Participants

Reaction Conditions

Reaction Steps

A solution of 2,2-dimethyl-propionic acid 8-(4-acetylamino-benzyl)-3-butyl-2,6-dioxo-1,2,3,6-tetrahydro-purin-7-ylmethyl ester (100 mg, 0.21 mmol) in N,N-dimethylformamide (2.0 mL) was treated with sodium carbonate (68 mg, 0.64 mmol), (2-bromomethyl-phenoxy)-tert-butyl-dimethyl-silane (70.6 mg, 0.23 mmol) in N,N-dimethylformamide (0.5 mL), and tetrabutylammonium iodide (24 mg, 0.06 mmol). The reaction was heated at 50° C. for 4 h. At this time, the reaction was poured onto a solution of water (125 mL) and a IN aqueous hydrochloric acid solution (1.28 mL). The product was extracted into 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, 1:4 ethyl acetate/petroleum ether) afforded 2,2-dimethyl-propionic acid 8-(4-acetylamino-benzyl)-3-butyl-1-[2-(tert-butyl-dimethyl-silanyloxy)-benzyl]-2,6-dioxo-1,2,3,6-tetrahydro-purin-7-ylmethyl ester (91.9 mg, 63%) as an off-white foam: FAB-HRMS m/e calcd for C37H51N5O6Si (M+H)+ 690.3687, found 690.3685.

Provenance & Evidence