PREPARATION OF ELECTROPHORIC DERIVATIVES OF N7-(2-HYDROXY-ETHYL)GUANINE, AN ETHYLENE-OXIDE DNA ADDUCT

Ethylene oxide, a potential human carcinogen, mainly damages DNA by reacting at guanine sites to form N7-(2-hydroxyethyl)guanine. In order to determine this DNA adduct with high sensitivity by gas chromatography, we have prepared, for comparison purposes, four electrophoric derivatives. The two that are most promising to date are bis- and tris-pentafluorobenzyl products prepared by first chemically transforming the N7-(2-hydroxyethyl)guanine to a corresponding xanthine, and then reacting the latter with pentafluorobenzyl bromide. These two derivatives are obtained in good yields and give molar responses of 0.6 and 0.5, respectively, relative to that of lindane by gas chromatography with electron-capture detection. © 1990.