The donor-acceptor-acceptor (DAA) arrangement of hydrogen bonding sites in 2- carboxamidonaphthyridines (eg 1) allows it to pair with guanine (2) in much the same way that cytosine does. Indeed, an HPLC bonded phase generated by covalently linking la to silicagel (R=(CH2) lo-SiMezO-silica) showed excellent retention of tri-0-acetylguanosine.'We recently quantified the strength of this interaction and found that ...