trans-4-(4-methoxy-benzothiazol-2-yloxy)-cyclohexylamine (0.5 mmol, intermediate 25.b) and 3-oxo-3,4-dihydro-2H-benzo[1,4]oxazine-6-carbaldehyde (0.5 mmol) were dissolved in DCE (4 ml) and MeOH (4 ml). The mixture was stirred at RT overnight, NaBH4 (1 eq) was added and stirring continued for 1 h. The reaction mixture was partitioned between DCM and NH4OH. The organic layer was dried over MgSO4 and concentrated under reduced pressure. Purification by chromatography (EtOAc/MeOH 9:1 +1% NH4OH) and crystallisation from ether gave 36 mg (16%) of the title compound as a colourless solid.
