1280725-24-7Relevant articles and documents
First artificial acidic fluorescent receptors for caffeine and other xanthine alkaloids
Mahapatra, Ajit Kumar,Sahoo, Prithidipa,Goswami, Shyamaprosad,Fun, Hoong-Kun,Yeap, Chin Sing
experimental part, p. 99 - 108 (2011/10/13)
Recognition of three xanthine alkaloids caffeine, theobromine and theophylline with acidic fluorescent receptors has been achieved for the first time through the host-guest interaction. The designed receptors are based on the choice of different fluorophores as spacers which can accommodate the bicyclic xanthine guests in between the binding phenolic hydroxyl or carboxyl groups. Among all the xanthine alkaloids, caffeine being the strongest base, its binding constants were maximum though all the nitrogens of caffeine are methylated. Photochemically the trans isomers were converted to the cis isomers which generated cavities for better binding of the xanthine alkaloids. Receptor 4-{4-[4′-(3-Carboxypropoxy)phynylazo]phenoxy}butyric acid (5) has been shown to be most effective in enhancement of fluorescence intensity with caffeine complexation. The binding properties have been studied by a combination of experimental techniques such as UV-visible and fluorescence spectroscopy. Also solid state binding performance between receptor 4,4′-Diazenyldiphenol (4) and caffeine has been described.
