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.
利用容易获得的起始材料,设计并合成了一类具有四重 A
DDA/
DAAD 氢键阵列的新型
亚胺基和
脲基异质链。两条不同链之间的分子识别在很大程度上取决于取代基和相邻氢键之间的连接物,这导致这些异质双链在无极性溶剂中的稳定性从 103 M-1 到 >105 M-1 不等。特别是,通过在 A
DDA 阵列的末端衍生出电子吸收基团,可以观察到关联常数增加了一个数量级。代表性互补复合物的分子建模揭示了四个氢键阵列的结合模式,这与配对模式一致。