Studies on Chemical Synthesis of mRNAs. I. Synthesis and Properties of N2-Tritylguanosine Derivatives and Application to Synthesis of pGpUpU

Abstract

Abstract Trityl (Tr), 4-methoxytrityl (MMTr), and 4,4′-dimethoxytrityl (DMTr) groups were introduced into the 2-amino group of 2′,3′,5′-tri-O-acetylguanosine by treatment with the corresponding trityl chlorides in pyridine to afford the N2-tritylated guanosine derivatives in high yields. Similarly, the N6-tritylated adenosine derivatives were synthesized. The stability of the three kinds of trityl groups under acidic conditions were described. The MMTr and Tr groups were found to be suitable for the protection of the 2-amino group of guanosine in oligonucleotide synthesis. An appropriately protected N2-tritylguanosine 5 -phosphorodithioate derivative was synthesized and utilized for the synthesis of pGpUpU.