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To a suspension of Intermediate 8 (14.94 g, 68.5 mmol) in DMF (225 mL) was added TEA (18.98 mL, 137 mmol) and CDI (11.10 g, 68.5 mmol). The reaction was heated at 120 C. for 1 h followed by the addition of 4,4'-dimethoxybenzhydrlamine (14.99 g, 61.6 mmol). The reaction was heated at 115 C. for 1 h, diluted with CHCl3, washed with aq. HCl (1 M), deionized H2O and concentrated. The material was crystallized from the residue using EtOH to afford the title compound. HPLC/MS: 444.18 (M+1); Rt=2.90 min.
In N,N-dimethyl-formamide; for 0.0333333h;Heating;
To a solution of the free acid form of the product of Example 5 prepared above (0.252 g, 0.569 mmol) in DMF (5 mL) was added aq. tris(hydroxymethyl)aminomethane (0.569 mL, 0.569 mmol, 1 M). The reaction was heated with a heat gun for 2 min and concentrated affording the title compound. HPLC/MS: 444.22 (M+1); Rt=2.99 min.
The product of Example 5 (0.40 g, 0.90 mmol) was suspended in CH2Cl2 (40 mL) and the mixture was cooled in an ice-water bath. Boron tribromide (4.50 mL, 4.50 mmol, 1 M in CH2Cl2) was added, and the resulting slurry was allowed to come to RT and was stirred for 75 min. Water was added, the aq. layer was adjusted to pH=5, and the solids were isolated by filtration. The product was suspended in EtOAc (20 mL) and the resulting slurry was heated in a water bath at 80 C. for 20 min, then cooled to RT. The resulting white solid was collected by filtration and dried affording the title compound. HPLC/MS: 416.2 (M+1); Rt=2.21 min.
With potassium hydroxide; In N,N-dimethyl-formamide; for 0.0333333h;Heating;
To a solution of the free acid form of the product of Example 5 prepared above (0.308g, 0.695 mmol) in DMF (5 mL) was added aq. potassium hydroxide (0.695 mL, 0.695 mmol, 1 M). The reaction was heated with a heat gun for 2 min and concentrated affording the title compound. HPLC/MS: 444.17 (M+1); Rt=2.95 min.