Cytosine mercuration

Other reactions characterized for pyrimidine residues include mercuration at C-5 of cytosine or uracil (Hopman et al., 1986), cycloaddition to the 5,6-double bond of thymine and uracil (Cimino et al., 1985), and thiolation at the C-4 amino group of cytosine (Malcom and Nicolas, 1984). 

Cytosine and uracil are readily mercurated (7.2.V) at the 5 position in a warm, buffered solution containing mercuric acetate (Dale et al., 1975 Hopman et al., 1986a) (Table 7.21). Although this technique yields excellent results, the chemicals needed are very toxic. 

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