NMR studies of triplex formation-recognition of C center dot G base pairs by new heterocyclic systems

Sequence specific recognition of double stranded DNA by oligonucleotides is an important process for selective control of gene expression, However, tr iple-helix formation is limited to recognition of DNA homopurine strands. W e report herein the NMR recognition studies of C.G base pairs by new hetero cyclic systems like benzimidazole and benzoxazoles bearing an urea donor fu nction designed to bound to the O4 and N7 atoms of guanosine base.