As another non-limiting example, 4-tert-butyl-N-[5-hydroxy-4-methyl-2-(2-oxo-3-phenyl-2,3-dihydro-1H-indol-3-yl)-phenyl]-benzenesulfonamide (compound 1430) was synthesized by adding dropwise 4-tert-butyl-benzenesulfonyl chloride (8 g, 34 mmol) in 5 mL dichloromethane to a stirring solution of 5-Amino-2-methyl-phenol (4 g, 32 mmol) in 20 mL pyridine and letting the mixture spin overnight at room temperature. The resulting mixture was concentrated in vacuo and the product was purified by column chromatography to yield 8 g (78%) of 4-tert-butyl-N-(3-hydroxy-4-methyl-phenyl)-benzenesulfonamide. A mixture of 3-hydroxy-3-phenyl-1,3-dihydro-indol-2-one (3.9 g, 17 mmol), 4-tert-butyl-N-(3-hydroxy-4-methyl-phenyl)-benzenesulfonamide (7 g, 22 mmol) and p-toluenesulfonic acid (6.5 g, 32 mmol) in dichloroethane was refluxed for 12 hours. The resulting mixture was cooled to room temperature to yield a colorless solid. The solid was filtered and purified using column chromatography to yield 8 g (88%) of the desired product (compound 1430).
