Reaction Steps
A solution of 1.50 grams (3.09 mmol) of N-[4-[2-(2-amino-4,5,6,7-tetrahydro-4-oxo-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl]benzoyl]-L-glutamic acid diethyl ester in 25 ml 1N NaOH was stirred at room temperature for 3 hours. The solution was carefully acidified to a of pH 2.8 by addition of 6M aqueous HCl and the resulting suspension was then filtered The precipitate was consecutively washed with 20 ml water, 10 ml methanol, 10 ml ether, and dried overnight at 50° C. and 10 torr. 1.13 g (85% of theory) of N-[4-[2-(2-amino-4,5,6,7-tetrahydro-4-oxo-3H-pyrrolo[2,3-d]pyrimidin-5-yl)ethyl]benzoyl]-L-glutamic acid was obtained as an amorphous solid. Selected data: 1H NMR (DMSO-d6) δ 12.20 (bs, 2H), 9.83 (bs, 1H), 8.48 (d, J=7.7 Hz, 1H), 7.74 (d, J=8.1 Hz, 2H), 7.26 (d, J=8.1 Hz, 2H), 6.32 (bs, 2H), 6.28 (bs, 1H), 4.33 (m, 1H), 3.43 (m, 1H), 3.01 (m, 2H), 2.61 (t, J=8.0 Hz, 2H), 2.30 (t, J=7.4 Hz, 2H), 1.96 (m, 3H), 1.54 (m, 1H); 13C NMR (DMSO-d6) δ 173.7, 173.1, 169.4, 166.5, 159.0, 156.7, 146.2, 131.4, 127.9, 127.2, 89.1, 52.1, 49.3, 36.9, 35.5, 32.3, 30.5, 26.2; IR (KBr) 3366, 2931, 1639, 1503, 1451, 1091 cm-1 ; MS(FAB) m/z 430 (MH+); UV (EtOH) 220 nm (ε 27 660), 280 (11 300).
