gadolinium N-(2-butyryloxyethyl)-N'-(2-ethyloxyethyl)-N,N'-bis(N'',N''-bis(carboxymethyl)acetamido)-1,2-ethanediamine
gadolinium n-(2-butyryloxyethyl)-n'-(2-ethyloxyethyl)-n,n'-bis(n'',n''-bis(carboxymethyl)acetamido)-1,2-ethanediamine