Answer
Tioguanine, a sulphydryl analogue of guanine, is activated to thioguanylic acid; its metabolites inhibit de novo purine synthesis and purine nucleotide interconversions, and its incorporation into DNA is claimed to contribute to cytotoxicity.
Sources for this answer
- Tioguanine 40 mg TabletsAspen · emc · SmPC §5.1 Pharmacodynamic properties · Version 9Document updated
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