Sequence modification in copoly(ester-imide)s: a catalytic/supramolecular approach to the evolution and reading of copolymer sequence information

Abstract

Catalytic ester-interchange reactions, analogous to mutation and recombination, allow new sequence information to be written statistically into poly(ester-imide) chains based on NDI (1,4,5,8-naphthalenetetracarboxylic diimide) units. Thus, both the insertion of the cyclic ester cyclopentadecanolide (“exaltolide”) into an NDI-based homopolymer and quantitative sequence exchange between two different homopoly(ester-imide)s are catalyzed by di-n-butyl tin(IV) oxide. Emerging sequences are identified at the triplet and quintet levels using supramolecular complexation of pyrene-d10 at the NDI residues to amplify the separation of 1H NMR resonances associated with different sequences. In such systems, pyrene is able to act as a “reader molecule” by generating different levels of ring-current shielding from the different patterns of supramolecular binding to all NDI-centered sequences of a given length.

Discrete, self-immolativeN-substituted oligourethanes and their use as molecular tags

“…12–16 Indeed, while our group and others have successfully demonstrated the storage of information within the primary structure of sequence-defined macromolecules, the majority of those studies relied on the use of MS/MS for decoding purposes. 17–26…”

“…[12][13][14][15][16] Indeed, while our group and others have successfully demonstrated the storage of information within the primary structure of sequencedefined macromolecules, the majority of those studies relied on the use of MS/MS for decoding purposes. [17][18][19][20][21][22][23][24][25][26] Using an analogous self-immolation process, Lutz and coworkers demonstrated that increasing the spacer length between the carbamate and the terminal alcohol of N-substituted oligourethanes resulted in decreased depolymerization kinetics. 27 In addition, the depolymerization could be completely stalled by making use of a longer hexyl spacer, which was utilized by the authors as a method to selectively erase specific parts of an informational sequence.…”