Alloxan analogues as potential pancreatic-imaging radiopharmaceuticals

Three families of alloxan derivatives, 5-arylthiobarbituric, 5-aryliminobarbituric, and 5-aryldialuric acids, were prepared as prospective radioiodine-transporting radiopharmaceuticals for the delineation of pancreatic insulinomas. Members of each class were screened for effects on blood sugar levels in a rat glucose tolerance assay. Transient hyperglycemia was observed with 5-(2,4-dichlorophenyl)iminobarbituric acid. No agent evaluated induced permanent diabetes at the doses tested.