abstract |
The 2,4,5,7-tetraaminopyrimido[5,4-g]pteridine characterized by a hue-angle h of not less than 98, processes for preparing the pteridine I of the invention, novel, insoluble 2,4,5,7-tetraaminopyrimido[5,4-g]pteridine salts, their preparation and the use of the pteridines of the invention. |