Regulation of Duplex Formation in Response to pH and Complementary RNA: Development of Oligonucleotides Modified with <i>S</i>‑Methylthioimidate-Bridged Nucleic Acid and Evaluation of Their Function.

ABSTRACT: Biomaterials such as oligonucleotides that can control their functions in response to pH are highly useful in the fields of biotechnology. In this study, S-methylthioimidate-bridged nucleic acid (Me-TIBNA) was designed to transform 2'-aminothymidine into an amido-bridged nucleic acid (AmNA), allowing for the modulation of oligonucleotide functionality in response to pH changes. Me-TIBNA-modified oligonucleotides were synthesized to investigate alkaline intramolecular cyclization subsequent to the acidic hydrolysis of the thioimidate bridge moiety. The results revealed that Me-TIBNA could be converted to 2'-aminothymidine, followed by the condensation of the amine and thioester under basic conditions to yield AmNA. Interestingly, the presence of a complementary RNA enhanced the alkal

SUBMITTER: Osawa T 

PROVIDER: S-EPMC12824751 | biostudies-literature | 2026 Jan

REPOSITORIES: biostudies-literature