School of Chemistry, University of Southampton, Southampton, SO17 1BJ UK.
Chemistry. 2010 Nov 2;16(41):12387-97. doi: 10.1002/chem.201001861.
A series of pyridyl guanidinium-carboxylates has been prepared and the dimeric self-assembly of these studied in H(2)O/DMSO mixtures, principally using dilution isothermal calorimetry. Compounds 5 and 6, incorporating an aromatic ring in the "tethering" region between the guanidinium and carboxylate groups, demonstrate the strongest dimerisation in neat DMSO. X-ray crystal structures of 5 and 6 reveal two different dimerisation architectures in the solid-state, but both involve carboxylate-guanidinium salt bridges as anticipated, and π-π interactions. Compounds 10-16 incorporating peptidic fragments between the guanidinium and carboxylate groups, showed reduced dimerisation strength with increased amino acid content, but also sustained dimerisation under increasingly aqueous conditions, up to 50% H(2)O/DMSO in the case of 14 and 15. The extent of our study in H(2)O/DMSO mixtures was determined by substrate solubility of 10-16, and not the limit of self-assembly.
已经制备了一系列吡啶胍基羧酸酯，并在 H（2）O/DMSO 混合物中研究了这些化合物的二聚体自组装，主要使用稀释等温量热法。化合物 5 和 6 在胍基和羧酸酯基团之间的“连接”区域中包含一个芳环，在纯 DMSO 中表现出最强的二聚化。5 和 6 的 X 射线晶体结构揭示了在固态中两种不同的二聚体架构，但都涉及预期的羧酸-胍盐桥和π-π相互作用。在胍基和羧酸酯基团之间包含肽片段的化合物 10-16 随着氨基酸含量的增加，二聚化强度降低，但在越来越水的条件下也能维持二聚化，在 14 和 15 的情况下高达 50%的 H（2）O/DMSO。我们在 H（2）O/DMSO 混合物中的研究程度取决于 10-16 的底物溶解度，而不是自组装的极限。
