Patent ID: 6489326
Filing Date: 2002-12-03
Classification: A61K,A61P,C07D

Abstract:
A method for manufacturing of 5-amino-2,3-dihydrophthalazine-1,4-dione sodium salt comprising the following steps:(a) interaction of 3-nitro-phmalanhydride with hydrazine hydrate in acetic acid at 90-120Â° C. yielding in a product of interaction; (b) reduction of the product of interaction formed on step (a) by hydrazine hydrate in a water-alkaline medium in presence of a skeletal nickel catalyst with forming of a reaction mixture containing 5-amino-2,3-dihydrophthalazine-1,4-dione; (c) isolation of 5-amino-2,3-dihydrophthalazine-1,4-dione from the reaction mixture formed on step (b); (d) treatment of 5-amino-2,3-dihydrophthalazine-1,4-dione at 20-80Â° C. by sodium hydroxide with addition of a lower alcohol or ketone with forming of a mixture containing 5-amino-2,3-dihydrophthalazine-1,4-dione sodium salt; (e) isolation of 5-amino-2,3-dihydrophthalazine-1,4-dione sodium salt from the mixture formed on step (d).