115421-52-8Relevant articles and documents
Hg(II) selective complexation by chromoionophoric Calix[4]arene derivative
Qazi, Mansoor Ahmed,Qureshi, Imdadullah,Memon, Shahabuddin
, p. 1231 - 1238 (2011)
The present article describes an exploration regarding Hg(II) selective complexation behavior of 5,11,17,23- tetrakis[(N,N-dimethylamino)methyl]-25,26, 27,28- tetrahydroxycalix[4]arene (4). The binding affinity of 4 toward selected transition metal ions such as Cd(II), Co(II), Cu(II), Hg(II), Ni(II), Pb(II) and Zn(II) have been investigated by UV-visible and fluorescence spectroscopic techniques. From the results it has been noticed that 4 confers a pronounced preference for Hg(II) in complexation phenomenon even in the presence of other metal ions. The results of Job's plot analysis reveal 1:1 host-guest complex formation between Hg(II) and 4. The FT-IR spectroscopy also supports the complexation affinity of 4 for Hg(II). Springer Science+Business Media, LLC 2011.
New efficient synthetic pathways to tetrakis{p-[(diethylphosphono)methyl]} calix[4]arene
Mourer, Maxime,Regnouf-De-Vains, Jean-Bernard
, p. 766 - 771 (2012)
Various operating conditions have been applied on tetrakis[p- (halogenomethyl)]- and tetrakis[p-(aminomethyl)]calix[4]arene derivatives to improve the synthesis of the 5,11,17,23-tetrakis[(diethylphosphono)methyl]-25, 26,27,28-tetrahydroxycalix[4]arene. Two new, high yield, synthetic pathways have been selected, involving, for the first one, the 25,26,27,28-tetrahydroxy-5,11, 17,23-tetrakis[(trimethylamino)methyl]calix[4]arene, tetraiodide, DMF, and 10 equiv. of triethyl phosphite ((EtO)3P), and, for the other one, the 5,11,17,23-tetra(bromomethyl)-25,26,27,28-tetrahydroxycalix[4]arene, CH 2Cl2, and only 4 equiv. of (EtO)2P. Copyright
Differential recognition of d and l-alanine by calix[4]arene amino derivative
Memon, Fakhar N.,Memon, Shahabuddin
, p. 413 - 420 (2013)
Biomolecules that exist in two enantiomeric forms are generally characterized by their physiological action, e.g. l-alanine is a physiological active form of an essential amino acid. The recognition/separation of one of the enantiomers is an important task as they are used as food supplement or pharmacological products where essentially pure enantiomeric forms are required. Therefore, the quantitation of undesirable enantiomers in drug raw material is the challenging task for pharmacists and chemists. Present study demonstrates the differential recognition of l-alanine amino acid by 5,11,17,26-tetrakis-[(N, N-dimethylamino)methyl]-25,26,27,28-tetrahydroxy-calix[4]arene (3). Another characteristic feature of this study is the use of methyl orange as a UV-visible spectrophotometric probe for the determination of stability constant of host-guest inclusion complexes by adopting competitive inclusion method and 1:1 complexation ratio was confirmed by Benesi-Hildebrand equation. Thermodynamics of the recognition have been evaluated that provided the significant distinction for both isomers, i.e. d and l-alanine and it has been deduced that compound 3 may be employed in chromatographic columns for their separation. Thus, the study provides a broad spectrum of its applications in varying fields of analytical and pharmaceutical science. Springer Science+Business Media Dordrecht 2012.
