(nitrilotrimethandiyl)tris(phosphonsyre), {ethan1,2diylbis[nitrilobis(methylen)]}tetrakis(phosphonsyre), [(bis{2[bis(phosphonomethyl)amino]ethyl}amino)methyl]phosphonsyre syre, {hexan1,6diylbis[nitrilobis(methylen)]}tetrakis(phosphonsyre), {[(2hydroxyethyl)imino]bis(methylen)}bis(phosphonsyre) og [(bis{6 [bis(phosphonomethyl)amino]hexyl}amino)methyl]phosphonsyre; salte deraf