Formaldehyde → 1-[5-Bromo-6-hydroxy-7-(morpholinomethyl)-1,3-benzothiazol-2-yl]-3-ethyl-urea

Participants

Reaction Steps

Paraformaldehyde (29 mg, 0.05 mmol) was suspended in anhydrous DMF (2 mL) under argon and morpholine (0.08 mL, 0.95 mmol) added. The mixture was stirred at RT for 10 min then Intermediate 6 (200 mg, 0.63 mmol) added. The mixture was stirred at RT overnight, heated to 90° C. for 2 h then cooled to RT. The mixture was diluted with H2O and a precipitate formed. EtOAc was added but the precipitate remained insoluble. The suspension was filtered through a PTFE filter and the solid rinsed with H2O and EtOAc. The biphasic filtrate was extracted into EtOAc (4×20 mL). The combined organic layers were washed with H2O (3×50 mL), dried (Na2SO4) and concentrated in vacuo. The material was purified by chromatography, on silica eluting with 0-10% MeOH in DCM to give Intermediate 12 (28 mg, 11%).

Provenance & Evidence