DNA-Cleavage studies on N-substituted monocyclic enediynes: enhancement of potency by incorporation of intercalating or electron poor aromatic ring and subsequent design of a novel phototriggerable acyclic enediyne

A number of novel N-substituted enediynes (azaenediynes) 1–4 were synthesized as DNA cleaving agents. Enhancement of DNA cleavage potency was observed with those compounds which could interact with DNA through intercalation of the extended aromatic ring or through electrostatic attraction with electron poor aromatic ring. An acyclic enediyne 5 with a novel phototriggerable device was also synthesized and its DNA-cleaving activity was established.