DNA Alkylation of the RUNX‐Binding Sequence by CBI–PI Polyamide Conjugates**

Many types of molecular targeted drugs that inhibit cancer growth by acting on specific molecules have been developed. The runt-related transcription factor (RUNX) family, which induces cancer development by binding to a specific DNA sequence, has attracted attention as a new target for cancer treatment. We have developed Chb-M ¢ , which targets the RUNX-binding sequence. Chb-M ¢ was developed by conjugating pyrrole-imidazole (PI) polyamides and chlorambucil as an anticancer agent. It was recently reported that Chb-M ¢ had a remarkable anticancer effect in vivo. In this study, to explore the possibility of an alternative structure, we designed a new series of CBI-PI polyamides, in which seco-CBI was applied as a DNA-alkylating agent. We examined the characteristics of the CBI-PI polyamides targeting the RUNX-binding sequence and found that these conjugates have great potential for cancer treatment.