Synonyms: 1,2-Ethanediyl bis{4-[(2,5-dioxo-1-pyrrolidinyl)oxy]-4-oxobutanoate};Butanoic acid, 4-[(2,5-dioxo-1-pyrrolidinyl)oxy]-4-oxo-, 1,2-ethanediyl ester;Poly(oxy-1,2-ethanediyl), alpha-(4-((2,5-dioxo-1-pyrrolidinyl)oxy)-1,4-dioxobutyl)-omega-(4-((2,5-dioxo-1-pyrrolidinyl)oxy)-1,4-dioxobutoxy)-