Table 2.
PAH-N6-dA adduct | Topology | Distortion energy (kcal/mol) | VDW stacking interaction energy (kcal/mol) | Distortion + VDW (kcal/mol) | ΔTm (°C)a | NERf |
---|---|---|---|---|---|---|
R B[c]Ph | Fjord 3 rings | 13.0 | −21.0 | −8.0 | −0.5 b,c | Resistant |
S B[c]Ph | Fjord 3 rings | 14.4 | −21.8 | −7.4 | −0.5 b,c | Resistant |
R B[a]P | Bay 4 rings | 14.7 | −23.5 | −8.8 | −11.8 b,d | Modest |
S B[a]P | Bay 4 rings | 17.8 | −22.8 | −5.0 | −18.8 b,d | Greatest |
R DB[a,l]P | Fjord 5 rings | 10.8 | −28.1 | −17.3 | +7.7 b,e | Resistant |
S DB[a,l]P | Fjord 5 rings | 14.9 | −24.7 | −9.8 | −5.5 b,e | Resistant |
ΔTm = Tm (Lesion-containing duplex) − Tm (Unmodified);
Sequence context: 5′-CTCTCA*CTTCC-3′;
Melting data for the B[c]Ph-modified duplexes are from 66;
melting data for the B[a]P-modified duplexes are from 64;
melting data for the DB[a,l]P-modified duplexes and the unmodified duplex are from 65; the Tm for the unmodified duplex is 43.8 ± 0.5 °C.