2-amino-5-tert-butylfuran-3-carbonitrile

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: To a solution of 4-chloro-5,6,7,8-tetrahydrobenzo[1,2-b]pyrimidino[5,4-d]selenophene (500 mg, 1.83 mmol, from step b of example 1) in DMF (15 mL) was added sequentially 2-amino-5-tert-butylfuran-3-carbonitrile (300 mg, 1.83 mmol) and powdered NaOH (210 mg, 5.49 mmol) at rt. Work-up as described in example 2, gave the product as a yellow color solid (400 mg, 55%), mp 230-232° C. 1H NMR (400 MHz, CDCl3): δ 9.78 (1H, s, H-2), 6.94 (1H, br s, exchangeable with D2O, —NH), 6.35 (1H, s, H-4′), 3.30-3.31 (2H, m, H-8), 2.95 (2H, br s, H-5), 1.90-1.92 (4H, m, H-6,7), 1.38 (9H, s, tert-butyl); 13C NMR (100 MHz, CDCl3): δ 163.2, 161.7, 158.0, 154.0, 144.7, 142.9, 137.1, 133.8, 125.9, 101.4, 97.8, 33.0, 29.0, 28.8, 28.4, 23.1, 22.5; LC-MS (positive ion mode): m/z 399, 401 (M+H)+.