To a solution of ethyl 1,4-dimethoxy-2-methylnaphthalene-3-carboxylate (73 mg, 0.266 mmol) in carbon tetrachloride (10 ml) was added N-bromosuccinimide (47 mg, 0.266 mmol) and dibenzylperoxide (5 mg). The mixture was heated at reflux under nitrogen for 45 min, illuminating with a 200 W lamp. The reaction was cooled to room temperature, 4-aminophenyl acetic acid (40 mg, 0.266 mmol), triethylamine (74 μl, 0.53 mmol) and DMF (5 ml) added and the reaction stirred for 48 h. Acetic acid (glacial, 1 ml) was added to the reaction and the mixture refluxed for 3 h under nitrogen. Sodium metabisulphite solution (1 ml) was added and the reaction evaporated to dryness under vacuum. The product was partially purified by SPE (NH2, 10 g) eluting with methanol then 5% acetic acid in methanol. The fractions containing product were passed through a silica plug washing with 5% acetic acid in methanol. After evaporation of the solvents under vacuum, the residue was columned on a silica gel flash column eluting with a gradient (1:1 ethyl acetate/cyclohexane to 5% methanol, 1% acetic acid in 1:1 ethyl acetate/cyclohexane) to give [4-(4,9-dimethoxy-1-oxo-1,3-dihydro-2H-benzo[f]isoindol-2-yl)phenyl]acetic acid (15 mg, 15%).
