Potent anti-viral 5-(2-bromovinyl) uracil nucleosides are inactive at inducing gene mutations in Salmonella typhimurium and V79 Chinese hamster cells and unscheduled DNA synthesis in primary rat hepatocytes.

(E)-5-(2-bromovinyl)-2'-deoxyuridine (BDVU), one of the most potent and selective anti-herpes agents described to date, and its close congeners (E)-5-(2-bromovinyl)-1-beta-D-arabinofuranosyluracil (BVaraU) and (E)-5-(2-bromovinyl)uracil (BVU), as well as the reference compounds 5-iodo-2'-deoxyuridine (IDU) and 5-trifluoro-2'-deoxythymidine (TFT) were examined for their genotoxic potential. With the exception of a weak activity of TFT in the newly developed strain TA 102, none of the compounds was active in a bacterial cell mutagenesis (Salmonella/microsome) assay. Nor did they induce DNA repair (unscheduled DNA synthesis) in primary rat hepatocytes. In a mammalian cell mutagenesis assay using V79 Chinese hamster cells, the reference compounds IDU and TFT proved highly cytotoxic and mutagenic, whereas BVDU, BVaraU and BVU were neither cytotoxic nor mutagenic.