Synthesis, Structure, and Inclusion Capabilities of Trehalose-Based Cyclodextrin Analogues (Cyclotrehalans)
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- 作者：David Rodrí ; guez-Lucena ; Juan M. Benito ; Eleuterio Á ; lvarez ; Carlos Jaime ; Javier Perez-Miron ; Carmen Ortiz Mellet ; José ; M. Garcí ; a Ferná ; ndez
- 刊名：Journal of Organic Chemistry
- 出版年：2008
- 出版时间：April 18, 2008
- 年：2008
- 卷：73
- 期：8
- 页码：2967 - 2979
- 全文大小：522K
- 年卷期：v.73,no.8(April 18, 2008)
- ISSN：1520-6904
文摘
Concise and efficient strategies toward the synthesis of D2h- and D3h-symmetric cyclodextrin analoguesalternating 
mages/gifchars/alpha.gif" BORDER=0>,mages/gifchars/alpha.gif" BORDER=0>'-trehalose disaccharide subunits and pseudoamide segments (cyclotrehalans, CTs) arereported. The conformational properties of these cyclooligosaccharides are governed by the rigidity ofthe mages/gifchars/alpha.gif" BORDER=0>,mages/gifchars/alpha.gif" BORDER=0>'-trehalose disaccharide repeating unit and the partial double-bond character of the N-(C=X)linkages. In contrast to the typical concave-shaped cavity of cyclodextrins (CDs), CTs feature a convex-shaped hydrophobic cavity in which the mages/gifchars/beta2.gif" BORDER=0 ALIGN="middle">-face of the monosaccharide subunits is oriented toward theinner side, as supported by NMR and modeling (molecular mechanics and dynamics) studies. In the caseof cyclodimeric CTs (CT2s), the existence of intramolecular hydrogen bonds results in collapsed cavities,too small to allow the formation of inclusion complexes with organic molecules. Cyclotrimeric CTs(CT3s) display cavity sizes that are intermediate between those of mages/gifchars/alpha.gif" BORDER=0>CD and mages/gifchars/beta2.gif" BORDER=0 ALIGN="middle">CD, ideally suited for thecomplexation of complementary guests with ternary symmetry such as adamantane 1-carboxylate (AC).The higher flexibility of the pseudoamide bridges as compared with classical glycosidic linkages endowthese glyconanocavities with some conformational adaptability properties, making them better suitedthan CDs for complexation of angular guests, as seen from comparative inclusion capability experimentsagainst the fluorescent probes 6-p-toluidinonaphthalene-2-sulfonate (TNS; linear) and 8-anilinonaphthalene-1-sulfonate (ANS; angular).