SELECTIVE STABILIZATION OF AT-RICH DNA-DNA DUPLEXES BY OLIGODEOXYRIBONUCLEOTIDE CONJUGATES WITH DISTAMYCIN ANALOGS

Oligodeoxyribonucleotide conjugates with distamycin analogues containi ng up to five pyrrolecarboxamide moieties were synthesized. The stabil ity of duplexes formed by these conjugates was shown to depend directl y upon the number of pyrrolecarboxamide moieties in the ligand molecul e. For the duplexes formed by octaadenylate and octathymidilate conjug ates with the distamycin pentapyrrole analogue, stability was demonstr ated to be achieved by either one or two ligand molecules; however, du plexes containing two ligand molecules are more stable.