Ontology highlight
ABSTRACT:
SUBMITTER: Edwards SJ
PROVIDER: S-EPMC4405043 | biostudies-literature | 2015 Apr
REPOSITORIES: biostudies-literature
Edwards Sophie J SJ Valkenier Hennie H Busschaert Nathalie N Gale Philip A PA Davis Anthony P AP
Angewandte Chemie (International ed. in English) 20150217 15
Exceptionally powerful anion receptors have been constructed by placing squaramide groups in axial positions on a steroidal framework. The steroid preorganizes the squaramide NH groups such that they can act cooperatively on a bound anion, while maintaining solubility in nonpolar media. The acidic NH groups confer higher affinities than previously-used ureas or thioureas. Binding constants exceeding 10(14) M(-1) have been measured for tetraethylammonium salts in chloroform by employing a variat ...[more]