title: Fluorescence sensing and selective binding of L- and D-tryptophan-modified permethylated beta-cyclodextrins for aliphatic oligopeptides.
abstract: Two tryptophan-modified permethylated beta-cyclodextrins, 6I-L-Trp-6I-deoxy-2I,3I-di-O-methyl-hexakis(2II-VII,3II-VII,6II-VII-tri-O-methyl-beta-cyclodextrin (3) and 6I-D-Trp- 6I-deoxy-2I,3I-di-O-methyl-hexakis(2II-VII,3II-VII,6II-VII-tri-O-methyl)-beta-cyclodextrin (4), were synthesized, and their binding behaviors were investigated with the aliphatic oligopeptides, Leu-Gly, Gly-Leu, Gly-Pro, Glu-Glu, and Gly-Gly. Fluorescence spectrophotometric studies indicated that 3 and 4 can act as efficient fluorescence sensors for aliphatic oligopeptides. Due to their intermolecular co-inclusion binding mode with substrates, 3 and 4 not only afforded high binding constants of up to 10(3)-10(4) M(-1) for guest oligopeptides but also good molecular selectivities of up to ca. 7 for Gly-Gly/Leu-Gly and Glu-Glu/Gly-Gly pairs.
authors: Department of Chemistry, State Key Laboratory of Elemento-Organic Chemistry, Nankai University, Tianjin 300071, PR China. yuliu@nankai.edu.cn
authors: Yu
authors: Y
authors: Liu
authors: Shu
authors: S
authors: Kang
authors: Yong
authors: Y
authors: Chen
authors: Jun
authors: J
authors: Shi
authors: Chen-Feng
authors: CF
authors: Ke
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D005453:Fluorescence; D008745:Methylation; D008968:Molecular Conformation; D009842:Oligopeptides / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism; D011485:Protein Binding; D014364:Tryptophan / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry*; D047392:beta-Cyclodextrins / Q000138:chemical synthesis / Q000737:chemistry* / Q000378:metabolism
chemical_list: C525741:6(I)-tryptophyl-6(I)-deoxy-2(I),3(I)-di-O-methylhexakis(2(II-VII),3(II-VII),6(II-VII)-tri-O-methyl)-beta-cyclodextrin; D009842:Oligopeptides; D047392:beta-Cyclodextrins; D014364:Tryptophan