Table 1.

Prompt (≤100 ns) yields of guanine radical cations (Φ_G [G^•+]), and rate constants of proton-coupled hole transfer reactions 2AP(−H)^• → G(−H)^• (rate constant k) that generate neutral guanine radicals via the oxidation of guanine bases by neutral 2AP radicals in DNA duplexes.^{36, 37}

Sequencea)	ΦG[G• +]	k, s−1
[2AP]TGGTTTTTTTTTTT	0.8±0.1	(5.0±0.5)×105b)
[2AP]TTGGTTTTTTTTTT	0.25±0.05	(1.0±0.1)×104
[2AP]TTTGGTTTTTTTTT	~ 0	(3.3±0.3)×103
[2AP]TTGGGTTTTTTTTT	n.d. c)	(1.8±0.2)×104

^a)Oligodeoxyribonucleotide sequences are written in the 5′ to 3′ direction. The complementary strands with T opposite the 2AP residue are not shown.

^b)The uncertainties are given as standard errors of the best least-squares fits of the appropriate fits of kinetic equations to the transient absorption profiles of the G(−H)^• decay curves recorded at 315 nm.

^c)n.d. = not determined.