dodecapotassium [ethane-1,2-diylbis[[(phosphonatomethyl)imino]ethane-2,1-diylnitrilobis(methylene)]]tetrakisphosphonate

1,2-Ethanediylbis[(phosphonomethyl)imino]bis[2,1-ethanediylnitrilobis(methylene)]tetrakisphosphonic acid dodecapotassium salt