Solid-phase synthesis of oligomeric deoxynucleic-thiourea (DNT) and deoxynucleic S-methylthiourea (DNmt): a neutral/polycationic analogue of DNA

A solid-phase synthesis for oligomeric DNmt is reported. Synthesis proceeds in 3′–5′ direction and involves coupling of a protected 3′-isothiocyanate with the corresponding 5′-amine of the growing oligo chain. The difference in oligomeric thiourea/S-methylthiourea binding to DNA is investigated.