Fully labeled dguo

ɣ-OH-Acr-dGuo and [¹³C₁₀¹⁵N₅]ɣ-OH-Acr-dGuo were prepared by reaction of acrolein with dGuo or fully labeled dGuo (Toronto Research Chemicals). The resulting products were characterized and quantified by ¹H NMR, using toluene as an internal standard, as previously described;^{19 (link)} εdAdo and [¹³C₅]εdAdo (labeled with ¹³C in the five carbons of the deoxyribose ring) were purchased from Toronto Research Chemicals (North York, Ontario, Canada). Reagents for DNA isolation were obtained from Qiagen (Germantown, MD). Calf thymus DNA, micrococcal nuclease and phosphodiesterase II were purchased from Worthington Biochemical Co. (Lakewood, NJ). Alkaline phosphatase and other solvents were obtained from Sigma-Aldrich Chemical Co. (Milwaukee, WI).

ɣ-OH-Acr-dGuo (1) and [¹³C₁₀¹⁵N₅]ɣ-OH-Acr-dGuo were prepared by reaction of acrolein with dGuo or fully labeled dGuo (Toronto Research Chemicals, North York, Ontario, Canada).^{28 (link)} 1,N⁶-etheno-dAdo (4), [¹³C₅]1,N⁶-etheno-dAdo, 8-oxo-dGuo (5), and [¹³C₂¹⁵N]8-oxo-dGuo were purchased from Toronto Research Chemicals. (6S,8S)ɣ-OH-Cro-dGuo (2), (6R,8R)ɣ-OH-Cro-dGuo (3), and [¹⁵N₅](6S,8S;6R,8R)ɣ-OH-Cro-dGuo were prepared as described. ^{29 (link)} The purities of the standards were tested by LC-MS and were greater than 95%. Reagents for DNA isolation were procured from Qiagen (Germantown, MD). Calf thymus DNA, micrococcal nuclease, and phosphodiesterase II were purchased from Worthington Biochemical Co. (Lakewood, NJ). Alkaline phosphatase and other solvents were obtained from Sigma-Aldrich Chemical Co. (Milwaukee, WI).

Acr-dGuo and [¹³C₁₀¹⁵N₅]Acr-dGuo (comprising both adducts 1 and 2) were prepared as described^{29 (link)} by reaction of acrolein with fully labeled dGuo (Toronto Research Chemicals); εdAdo, [¹³C₅]εdAdo (labeled with ¹³C in the five carbons of the deoxyribose ring), εdCyd and [¹³C¹⁵N₂]εdCyd (labeled with ¹³C in position 5, and with ¹⁵N in positions 4 and 6) were purchased from Toronto Research Chemicals (North York, Ontario, Canada). Reagents for DNA isolation were obtained from Qiagen (Germantown, MD). Calf thymus DNA, micrococcal nuclease and phosphodiesterase II were purchased from Worthington Biochemical Co. (Lakewood, NJ). Alkaline phosphatase and other solvents were obtained from Sigma-Aldrich Chemical Co. (Milwaukee, WI).