Reaction Steps
A mixture of (R)-3-methyl-3-(2-methyl-5-nitro-4-oxoquinazolin-3(4H)-yl)piperidine-2,6-dione (0.40 g, 1.2 mmol) and 10% Pd—C (0.2 g, 50% wet), in 200 mL of 3:1 ethyl acetate-methanol was shaken under 50 psi H2 for 3 hours. The mixture was filtered through Celite, and the solvent was evaporated. The residue was chromatographed on silica gel using a dichloromethane-acetonitrile gradient, providing (R)-3-(5-amino-2-methyl-4-oxoquinazolin-3(4H)-yl)-3-methylpiperidine-2,6-dione as an off-white solid (0.16 g 44% yield): HPLC, Waters Symmetry C-18, 3.9×150 mm, 5 μm, 1 ml/min, 240 nm, 20/80 CH3CN/0.1% H3PO4, 1.62 (98.71%); mp 295-297° C.; 1H NMR (DMSO-d6) δ 1.88 (s, 3H, CH3), 2.31-2.36 (m, 1H, CHH), 2.53-2.59 (m, 2H, 2CHH), 2.62 (s, 3H, CH3), 2.71-2.84 (m, 1H, CHH), 6.53-6.56 (m, 2H, Ar), 6.95 (br, 2H, NH2), 7.35 (t, J=8 Hz, 1H, Ar), 10.72 (s, 1H, NH); 13C NMR (DMSO-d6) δ 24.5, 26.3, 28.3, 29.0, 62.2, 104.2, 110.5, 110.8, 135.0, 147.4, 150.4, 152.9, 164.9, 171.5, 173.0; Anal. Calcd for C15H16N4O3: C, 59.99; H, 5.37; N, 18.66. Found: C, 59.73; H, 5.26; N, 18.69.
