Synonyms: 1H-Azepine,1,1'-(2,4,8,10-tetraoxa-3,9-diphosphaspiro[5.5]undecane-3,9-diyl)bis[hexahydro-,P,P'-dioxide; Phosphonic acid, (hexahydro-1H-azepin-1-yl)-, cyclicneopentanetetrayl ester (8CI);2,4,8,10-Tetraoxa-3,9-diphosphaspiro[5.5]undecane, 1H-azepine deriv.; NSC 84497