Show simple item record

dc.contributor.authorACHARYA, Aen_US
dc.contributor.authorRAMANUJAM, Ben_US
dc.contributor.authorCHINTA, JPen_US
dc.contributor.authorRAO, CPen_US
dc.date.accessioned2012-06-26T08:56:14Z
dc.date.available2012-06-26T08:56:14Z
dc.date.issued2011en_US
dc.identifier.citationJOURNAL OF ORGANIC CHEMISTRY,76(1)127-137en_US
dc.identifier.issn0022-3263en_US
dc.identifier.urihttp://dx.doi.org/10.1021/jo101759fen_US
dc.identifier.urihttp://dspace.library.iitb.ac.in/jspui/handle/100/14237
dc.description.abstractLower rim 1,3-diamido conjugates of calix[4]arene have been synthesized and characterized, and the structures of some of these have been established by single crystal XRD. The amido-calix conjugates possessing a terminal -COOH moiety have been shown to exhibit recognition toward guest molecules possessing -COOH moiety, viz., Asp, Glu, and reduced and oxidized glutathione (GSH, GSSG), by switch-on fluorescence in aqueous acetonitrile and methanol solutions when compared to the control molecules via forming a 1:1 complex. The complex formed has been shown by mass spectrometry, and the structural features of the complexes were derived on the basis of DFT computations. The association constants observed for the recognition of Asp/Glu by Phe-calix conjugate, viz., 532/676 M(-1), are higher than that reported for the recognition of Val, Leu, Phe, His, and Trp (16-63 M(-1)) by a water-soluble calixarene (Arena, G., et al. Tetrahedron Lett. 1999, 40, 1597). For this recognition, there should be a free -COOH moiety from the guest molecule. AFM, SEM, and DLS data exhibited spherical particles with a hundred-fold reduction in the size of the complexes when compared to the particles of the precursors. These spherical particles have been computationally modeled to possess hexameric species reminiscent of the hexameric micellar structures shown for a Ag(+) complex of a calix[6]arene reported in the literature (Houmadi, S., et al. Langmuir 2007, 23, 4849). Both AFM and TEM studies demonstrated the formation of nanospheres in the case of GSH-capped Ag nanoparticles in interaction with the amido-calix conjugate that possesses terminal -COOH moiety. The AFM studies demonstrated in this paper have been very well applied to albumin proteins to differentiate the aggregational behavior and nanostructural features exhibited by the complexes of proteins from those of the uncomplexed ones. To our knowledge, this is the first report wherein a amido-calix[4]arene conjugate and its amino acid/peptide/protein complexes have been differentiated on the basis of spectroscopy and microscopy studies followed by species modeling by computations.en_US
dc.language.isoEnglishen_US
dc.publisherAMER CHEMICAL SOCen_US
dc.subjectSelective Recognitionen_US
dc.subjectCluster Formationen_US
dc.subjectAqueous-Solutionen_US
dc.subjectL-Lysineen_US
dc.subjectComplexationen_US
dc.subjectDerivativesen_US
dc.subjectMoleculesen_US
dc.subjectSerineen_US
dc.title1,3-Diamido-calix[4]arene Conjugates of Amino Acids: Recognition of -COOH Side Chain Present in Amino Acids, Peptides, and Proteins by Experimental and Computational Studiesen_US
dc.typeArticleen_US


Files in this item

FilesSizeFormatView

There are no files associated with this item.

This item appears in the following Collection(s)

Show simple item record