NSC241275 Poly[imino[1-(2-carboxyethyl)-2-oxo-1,2-ethanediyl]imino[1-(hydroxymethyl)-2-oxo-1,2-ethanediyl]], .alpha.-(2-amino-3-hydroxy-1-oxopropyl)-.omega.-[[1-[[[2-[4-[bis(2-chloroethyl)amino]phenyl]-1-carboxyethyl]amino]carbonyl]-3-carboxypropyl]amino]-