α’, β’ van der Waals energy component maps to 25 kcal/mol. (A), 1R (+)-trans-anti-B[c]Ph-N6-dA adduct, χ = 10° (syn); (B), 1S(−)-trans-anti-B[c]Ph-N6-dA adduct, χ = 10° (syn); (C), 1R (+)-trans-anti-B[c]Ph-N6-dA adduct, χ = 200° (anti); (D), 1S(−)-trans-anti-B[c]Ph-N6-dA adduct, χ = 200° (anti).