Multifacial Recognition in Binary and Ternary Cocrystals from 5-Halouracil and Aminoazine Derivatives
作者:Gustavo Portalone、Kari Rissanen
DOI:10.1021/acs.cgd.8b00662
日期:2018.10.3
the components, always takes place between the more acidic site of the 5-halonucleobases (N3 atom) and the more basic site (imino N atom) of 2,4,6-triaminopyrimidine or 2,6-diaminopyridine, and melamine recognition unit results in being insufficiently basic to accept a proton. The general ability of pyrimidine nucleobases to provide electron donating groups to halogen bonding has been confirmed in seven
使用单晶X射线衍射进行了系统分析,以探讨潜在的组分间质子转移反应在尿嘧啶的5-卤代衍生物(A)与2-氨基腺嘌呤模拟物结合形成的AB共晶体的超分子结构中所发挥的作用。 (氨基嗪,B)。在不同的化学计量比下合成了十二种新的异二聚体,并通过溶剂共研磨然后溶液结晶而共结晶。在二元共晶体中,在5位(F,Cl,Br,I)进行卤化物修饰的尿嘧啶或1-甲基尿嘧啶与氨基芳香N偶联。-杂环(三聚氰胺,2,4,6-三氨基嘧啶,2,6-二氨基吡啶)作为嘧啶核苷碱基识别的多价位点。晶体学分析表明,除预期的中性三点氢键(TPI)外,受A→B质子转移青睐的离子化TPI可用于WC多面识别。值得注意的是,取决于组分的酸/碱性质的带电TPI的形成始终发生在5-卤代核碱基(N3原子)的更酸性位与2的更碱性位(亚氨基N原子)之间。 1,4,6-三氨基嘧啶或2,6-二氨基吡啶和三聚氰胺识别单元导致碱性不足以接受质子。在包含5-氯,5-溴或5-碘衍生物与三聚氰胺或2