INTRODUCTION OF 5 POTENTIALLY METABOLIZABLE LINKING GROUPS BETWEEN IN-111 CYCLOHEXYL EDTA DERIVATIVES AND F(AB')2 FRAGMENTS OF ANTICARCINOEMBRYONIC ANTIGEN-ANTIBODY .1. A NEW REPRODUCIBLE SYNTHETIC METHOD

The purpose of this study was to synthesize new bifunctional linker-ch elating agents for the modification of the in vivo distribution of In- 111-labeled antibodies. A general simple synthetic method of preparing cyclohexyl EDTA (CDTA) derivatives containing a linker/spacer group i s described. Linkers prepared included a diester, a six carbon aliphat ic chain, two thioethers and a disulfide group. The CDTA-linker compou nds were coupled to F(Ab')2 fragments of anti-carcinoembryonic antigen monoclonal antibody and labeled with In-111 with good retention of im munoreactivity.