| abstract |
Bleomycin's affinity for tumorous tissue and its ability to complex with cobalt has lead to its use in vivo as a complex with 57Cobalt. This complex has given excellent tumor images and has been useful for diagnostic purposes. Unfortunately, 57Co has the undesirable property of a 270 day half-life. The present invention provides a bleomycin analog which has a powerful meal-chelating substituent covalently bound to and chemically modifying a bleomycin. However, the inclusion of this chelating substituent in the bleomycin analog does not significantly modify the in vivo biological properties thereof with respect to unmodified bleomycin. The inventive bleomycin analog forms stable chelates with a variety of metal ions, and is particularly useful when labelled with radionuclides having short half-lives. So labelled, the bleomycin analog may be utilized for diagnostic purposes. |