Ethyl isothiocyanatoformate → 3-(2-Ethoxy-2-methylpropyl)-2-thioxanthine

Participants

Reaction Steps

Ethoxycarbonyl isothiocyanate (0.171 g, 1.30 mmol) was added to a stirred solution of 4-[(2-Ethoxy-2-methylpropyl)amino]-1H-imidazole-5-carboxamide (0.246 g, 1.09 mmol), which had been obtained from Example 1(c), in CH2Cl2 (1.1 mL) at r.t. for 0.5 h, then the reaction was left unstirred at 4° C. for 16 h. The reaction mixture was heated to r.t. for 1 h and the solvent was evaporated, the residue was dissolved in 2% sodium hydroxide (aq.) (27 mL) and the reaction was heated at 50° C. for 5.5 h. The pH was adjusted to neutral with conc. HCl and 1M HCl. The precipitate was collected by filtration, washed with water and purified by flash silica gel chromatography (CHCl3/MeOH; 20:1), to give the title compound in 47% yield (96 mg).

Provenance & Evidence