Photolabile-Protected Triazine-Based Janus G-C and Triple G-C-T Base-Coded Nucleobases for Supramolecular Polymer Construction

Janus self-assembling systems show unique behavior due to their dual-sided nature, enabling precise control over the assembly patterns and functional properties. Herein, we report the design and synthesis of photolabile-protected triazine-based nucleobase monomers featuring both Janus G-C and triple G-C-T base-coded motifs. These monomers, derived from DDA (G mimic), DAA (C mimic), and ADA (T mimic) arrays, possess polymerizable functionalities and self-complementary triple hydrogen-bonding sites. The O-nitrobenzyl (O-NB) protecting group imparts exceptional stability under both acidic and basic conditions, thereby enabling diverse polymerization conditions. A representative triple G-C-T monomer was polymerized via free-radical polymerization to yield the corresponding protected polymer, which, upon UV-induced deprotection, regenerated active hydrogen-bonding sites and triggered supramolecular self-assembly, as evidenced by enhanced mechanical performance. This study establishes a versatile synthetic platform for constructing nucleobase-derived Janus monomers with orthogonal reactivity and photochemically switchable supramolecular organizations.