Quadruply hydrogen-bonded heteroduplexes based on imide and urea units arrayed with ADDA/DAAD sequences†
Xianghui Li,Yiming Jia,Yi Ren,Youjia Wang,Jinchuan Hu,Teng Ma,Wen Feng,Lihua Yuan
Organic & Biomolecular Chemistry Pub Date : 08/20/2013 00:00:00 , DOI:10.1039/C3OB40998H
Abstract

A new class of imide- and urea-based hetero-strands with a quadruple ADDA/DAAD hydrogen-bond array was designed and synthesized from easily accessible starting materials. The molecular recognition between the two different strands depends highly on the substituents and the linker between neighboring hydrogen-bonds, which results in the stability of these heteroduplexes varying from 103 to >105 M−1 in apolar solvents. In particular, an increase of the association constant by up to one order of magnitude was observed by derivatizing the ADDA arrays at the termini with electron-withdrawing groups. Molecular modelling of the representative complementary complexes reveals the binding mode of four hydrogen-bond arrays that agrees with the matched pair.

Graphical abstract: Quadruply hydrogen-bonded heteroduplexes based on imide and urea units arrayed with ADDA/DAAD sequences