A mixture of 1-(3-(benzyloxy)pyridin-2-yl)thiourea (prepared according to Example 2, Steps A and B) (8.00 g, 30.8 mmol), 2-(4-bromo-3-oxobutyl)isoindoline-1,3-dione (12.8 g, 43.2 mmol; prepared according to J. Med. Chem. (1992) 35, 3239-3246), triethylamine (7.31 mL, 52.4 mmol), and ethanol (200 mL) was heated at reflux for 2 hours. The reaction mixture was cooled, diluted with water (200 mL), filtered, washed several times with water and hexanes, and dried. The product was recrystallized the solid from hexanes:methylene chloride (1:1, 250 mL) to afford 2-(2-(2-(3-(benzyloxy)pyridin-2-ylamino)thiazol-4-yl)ethyl)isoindoline-1,3-dione (13.8 g, 98.0% yield) as a white powder. 1H NMR (d6-DMSO) δ 9.93 (bs, 1H), 7.80-7.87 (m, 6H), 7.57 (d, 2H), 7.35-7.43 (m, 4H), 6.89 (m, 1H), 6.70 (s, 1H), 5.25 (s, 2H), 3.88 (t, 2H), 2.91 (t, 2H). Mass spectrum (apci) m/z=457 (M+H).
