186184-32-7Relevant academic research and scientific papers
Squaramido-based receptors: Molecular recognition of carboxylate anions in highly competitive media
Prohens, Rafel,Tomas, Salvador,Morey, Jeroni,Deya, Pere M.,Ballester, Pablo,Costa, Antoni
, p. 1063 - 1066 (2007/10/03)
A new series of artificial receptors for binding carboxylates has been developed. The receptors are base, on the hydrogen bonding abilities of secondary squaramides as binding subunits. The data reveal the formation of 1:1 complexes in highly competitive media. Using convenient spacers, receptors for di- and tri-carboxylates that incorporate two and three squaramide subunits have been prepared. The complexes are characterized by nmr and, when possible, by FAB spectral analysis.
Squaramido-based receptors: Design, synthesis, and application to the recognition of tetraalkylammonium compounds
Tomas, Salvador,Prohens, Rafel,Vega, Manuel,Rotger, M. Carmen,Deya, Pere M.,Ballester, Pablo,Costa, Antoni
, p. 9394 - 9401 (2007/10/03)
A new series of tripodal receptors based on squaramido rings as unprecedented binding units has been devised. Among the different structural possibilities that this functionality offers, the ability of establishing multiple O to C-H interactions has been explored. On this basis, new receptors capable of recognizing choline, acetylcholine, and related ammonium salts have been synthesized. Association constants in the range 103-104 M-1 have been measured by a 1H-NMR titration method using a 1:1 model. The formation of intracavity complexes is supported by the observation of characteristic changes in the NMR spectra of the complexes, of intermolecular cross peaks in 2D ROESY experiments, and by detection of signals corresponding to the molecular weight of the complexes by positive FAB mass spectrometry.
