919528-05-5 1,4,7,10-Tetraazacyclododecane-1,4,7,10-tetraacetic acid,1,4,7-tris(1,1-dimethylethyl) ester,10-[2-(5-carboxy-2-pyridinyl)hydrazide], 2,2,2-trifluoroacetate (1:2) 919528-56-6 1,4,7,10-Tetraazacyclododecane-1,4,7-triacetic acid,10-[2-[[[4-[2-[2-[(2R)-2-[[(1,1-dimethylethoxy)carbonyl]amino]-4-methyl-1-oxopentyl]hydrazinyl]-2-oxoethyl]phenyl]methyl]amino]-2-oxoethyl]-,1,4,7-tris(1,1-dimethylethyl) ester