Hydrochloric Acid → 6-Carboxy-3-[1-(6,7-dimethoxy-4-quinazolinyl)-4-piperidinyl]-1,2,3,4-tetrahydro-1-methyl-2,4-dioxo-quinazoline

Beteiligte Stoffe

Reaktionsschritte

In a solvent mixture of 30 ml of 1,4-dioxane and 5 ml of chloroform was suspended 245.0 mg (0.50 mmol) of Compound 63 obtained in Example 50. The suspension was added to a solution of hypobromous acid (3 mmol) which was prepared by adding 0.15 ml of bromine to a solvent mixture of 3 ml of a 2N aqueous solution of sodium hydroxide and 1 ml of 1,4-dioxane under ice cooling. The mixture was stirred at room temperature for one day, and then neutralized by addition of 4N hydrochloric acid, followed by extraction with chloroform. The organic layer was washed and dried, and the solvent was distilled off under reduced pressure. To the residue was added ether, and the precipitated crystals were collected by filtration and dried to give 52.4 mg (yield: 21%) of Compound 62 as white crystals.

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