Reaction Steps
4-(3-Chlorobenzyl)-3,4-dihydro-2-{2-[4-(2-guanidinoethyl)phenoxy]ethyl}-6-nitro-3-oxo-2H-1,4-benzoxazine (0.3 g) was warmed in ethanol (5 ml) and H2O (4 ml) until completely in solution. Iron powder (0.19 g, 6.8 eq) was stirred in followed by NH4Cl (0.02 g, 0.7 eq) and the reaction continued at reflux for 5 hours. While still hot, the mixture was filtered through celite and the yellow filtrate concentrated down to a yellow oil. After drying in vacuo at 80° C., the product was collected as a yellow solid in 85% yield, mp (dec) >94° C.; MS (CI) MH+ 494; IR (KBr) 3332, 1667, 1614, 1512, 1467, 1396, 1243, 830, 774, 680 cm-1 ; 1H NMR (DMSO-d6 /CDCl3) δ 7.66 (br s, 1H), 7.58-6.50 (v br s, 3H), 7.36 (m, 4H), 7.20 (m, 3H), 6.91 (d, 2H, J=8.6 Hz), 6.74 (d, 1H, J=8.4 Hz), 6.26 (d, 1H, J=2.2 Hz), 6.21 (dd, 1H, J=2.2, 8.4 Hz), 5.08 (d, 1H, J=16.7 Hz), 4.99 (d, 1H, J=16.5 Hz), 5.12-4.78(v br s., 1H), 4.79 (dd, 1H, J=4.0, 8.9Hz), 4.15 (m, 2H), 3.33 (m, 2H), 2.71 (t, 2H, J=7.5 Hz), 2.30 (m, 1H), 2.18 (m,1H). Anal. Calc'd for C26H28ClN5O3. HCl.0.5H2O: C 57.89, H 5.61, N 12.98. Found: C 57.64, H 5.48, N 12.63.
