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 6 M 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) 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).
