Synthesis and tumour-localizing properties of [F]-5-fluorocytosine-arabinoside and [F]-5-fluorocyclocytidine.

[F]-5-fluorocytosine-arabinoside ( 2) and [F]-5-fluorocyclocytidine ( 4) were prepared by reaction of [F]-acetylhypofluorite with cytosine-arabinoside ( 1) or cyclocytidine ( 3) in acetic acid and were isolated in an overall radiochemical yield of 20% and 9%, respectively. The biodistribution of both radiopharmaceuticals was determined in melanoma bearing Syrian golden hamsters. It was found that 2 is a good tumour-localizing agent for pigmented and non-pigmented Greene melanoma. [ABSTRACT FROM AUTHOR]