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Updated: Nov 1, 2025

Synthesis of Information-bearing Peptoids and their Sequence-directed Dynamic Covalent Self-assembly
Published on: February 6, 2020
Biomimetic hydrogen-bonding cascade for chemical activation: telling a nucleophile from a base
Hyunchang Park1, Dongwhan Lee1
1Department of Chemistry, Seoul National University 1 Gwanak-ro, Gwanak-gu Seoul 08826 Korea dongwhan@snu.ac.kr.
Abstract:
Hydrogen bonding-assisted polarization is an effective strategy to promote bond-making and bond-breaking chemical reactions. Taking inspiration from the catalytic triad of serine protease active sites, we have devised a conformationally well-defined benzimidazole platform that can be systematically functionalized to install multiple hydrogen bonding donor (HBD) and acceptor (HBA) pairs in a serial fashion. We found that an increasing number of interdependent and mutually reinforcing HBD-HBA contacts facilitate the bond-forming reaction of a fluorescence-quenching aldehyde group with the cyanide ion, while suppressing the undesired Brønsted acid-base reaction. The most advanced system, evolved through iterative rule-finding studies, reacts rapidly and selectively with CN- to produce a large (>180-fold) enhancement in the fluorescence intensity at λ max = 450 nm.
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