Sites of reaction of propane sultone with guanosine and DNA.

Propane sultone was reacted with guanosine and DNA at pH 6--7.5, and te reaction products were purified by Sephadex chromatography and h.p.l.c. The products were characterized by u.v. spectra, loss of tritium from the C-8 position and dissociation properties. The main product was shown to be an N-7-alkyl guanosine, accounting for greater than 90% of the total product. Similar evidence suggested that two of the minor adducts were N-1 and O6 alkyl derivatives, accounting for approximately 1.6 and 0.5% of the total adduct, respectively. N-7 and N-1 alkyl guanine were also detected in DNA reacted with propane sultone.