Abstract
An improved synthesis and purification of the hexadentate chelators, N,N,N,-tris[2-(3-hydroxy-2-oxo-1,2-dihydropyridin-1-yl) acetamido]ethylamine, 8a and N,N,N,-tris[2-(3-hydroxy-4-methyl-2-xo-1,2-dihydropyridin-1-yl) acetamido]ethylamine, 8b is described.