[CH:1]1([N:4]2[C:8]([C:9]3[CH:14]=[CH:13][CH:12]=[CH:11][CH:10]=3)=[CH:7][NH:6][C:5]2=[O:15])[CH2:3][CH2:2]1.Cl[CH2:17][C:18]([O:20][CH2:21][CH3:22])=[O:19].C(=O)([O-])[O-].[K+].[K+]>C(#N)C>[CH2:21]([O:20][C:18](=[O:19])[CH2:17][N:6]1[CH:7]=[C:8]([C:9]2[CH:10]=[CH:11][CH:12]=[CH:13][CH:14]=2)[N:4]([CH:1]2[CH2:3][CH2:2]2)[C:5]1=[O:15])[CH3:22]270 mg (1.35 mmol) of 1-cyclopropyl-5-phenyl-1,3-dihydro-2H-imidazol-2-one from Example 119A are dissolved in 5 ml acetonitrile and treated with 165 mg (1.35 mmol) of ethyl chloroacetate and 373 mg (2.70 mmol) of potassium carbonate. The mixture is stirred under reflux for 4 hrs, then a further 165 mg (1.35 mmol) of ethyl chloroacetate are added. After stirring overnight under reflux the reaction mixture is evaporated, the residue is partitioned between dichloromethane and water, the organic phase is separated, and this is dried over sodium sulphate and again concentrated. The crude product is purified by flash chromatography on silica gel (eluent: dichloromethane/methanol firstly 200:1, then 100:1) and thus yields 353 mg (91% of theory) of the target compound.
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