[CH3:1][O:2][C:3](=[O:16])[C:4]1[CH:9]=[C:8]([CH3:10])[CH:7]=[CH:6][C:5]=1[NH:11][C:12](=[O:15])[CH2:13][CH3:14].[Br:17]N1C(C)(C)C(=O)N(Br)C1=O>C(Cl)(Cl)Cl.C(Cl)(Cl)(Cl)Cl.C(OOC(=O)C1C=CC=CC=1)(=O)C1C=CC=CC=1>[CH3:1][O:2][C:3](=[O:16])[C:4]1[CH:9]=[C:8]([CH2:10][Br:17])[CH:7]=[CH:6][C:5]=1[NH:11][C:12](=[O:15])[CH2:13][CH3:14]The radical bromination was performed as described by Patil et al. 1989: 5-Methyl-2-propionylamino-benzoic acid methyl ester (8.85 g, 40 mmol) and 1,3-dibromo-5,5-dimethyl hydantoin (DDH) (5,72 g, 20 mmol) in a mixture of CHCl3 (500 mL) and CCl4 (500 mL) was heated to reflux. Every 60 minutes 50 mg of dibenzoyl peroxide was added for six hours and then the reaction mixture was left at reflux over night. It was then allowed to reach room temperature and the solvents were removed by evaporation. Chromatography using silica gel 60 and heptane/ethyl acetate (18:2 ->17:3 ->16:4) as eluent afforded the pure title compound (6.40 g, 53%).
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