Dendritic Galactosides Based on aβ-Cyclodextrin Core for the Construction of Site-Specific Molecular Delivery Systems: Synthesis and Molecular Recognition Studies

Cyclodextrin-based multivalent glycodisplays: covalent and supramolecular conjugates to assess carbohydrate–protein interactions

“…101 To overcome this limitation, the incorporation of different spacer segments between the CD core and the polyamino groups as well as between the glycoligands and the isothiocyanate functionality has been proposed. Santoyo-González, Roy and co-workers implemented the use of p-isothiocyanatophenyl glycosides in reaction with the amino-terminated per-(C-6)-thioalkyl derivative 31, 85,86 whereas Ortiz Mellet, Defaye, García Fernández and coworkers coupled aliphatic isothiocyanate-armed thioglycosides and the per-(C-6)-cysteaminyl bCD derivative 32 as a heptanucleophile. 102,103 In both cases multiconjugation reaction proceeded in high yield.…”

“…[84][85][86][87] Extensive specific lectin recognition studies were performed by different techniques, including classical ELLA, two-site ELLA (sandwich assay), turbidimetry and isothermal titration calorimetry (ITC). 86,88 It was demonstrated that the spacer arm was not a passive element regarding lectin binding or guest inclusion. Longer bridges often led to more efficient lectin recognition, whereas the effect of persubstitution at the primary face could be positive or detrimental for inclusion complex formation depending on the guest partner.…”

“…They also explored the incorporation of halogenarmed spacers at the primary positions of the CD platform to generate molecular diversity at the bridging segments (Scheme 10). [84][85][86][87] Extensive specific lectin recognition studies were performed by different techniques, including classical ELLA, two-site ELLA (sandwich assay), turbidimetry and isothermal titration calorimetry (ITC). 86,88 It was demonstrated that the spacer arm was not a passive element regarding lectin binding or guest inclusion.…”

“…Thermodynamic evidence for the formation of a ternary complex involving a heptavalent bLac conjugate with thioacetamido linkers, PNA lectin and 2-naphthalenesulfonate was obtained, supporting an inducedfit mechanism analogous to that depicted in Scheme 9. 86 Carpenter and Nepogodiev employed per-6-thio cyclodextrins as sulfur multinucleophiles and halogen-armed carbohydrates as substrates for the preparation of primary face-anchored glycoclusters, thereby reversing the location of the functional groups involved in the key multiple S N 2 reaction. 89 Per-6-thioaCD and -bCD (19) were obtained from the corresponding per-(C-6)-Br and per-(C-6)-I derivatives, respectively, by reaction with thiourea in the absence of oxygen followed by decomposition of the resulting thiouronium salts with aqueous NaOH.…”

Synthesis of cyclodextrin derivatives with monosaccharides and their binding with ampicillin and selected lectins

“…Although per-substitution of the primary hydroxyl groups of a cyclodextrin with carbohydrate moieties is expected to produce glycoclusters that bind stronger to lectins than the mono-analogs 14 the cavity inclusion ability may be decreased or increased, compared with the unsubstituted CDs, while hyperbranched derivatives may totally loose their cavity binding capacity. 14,20 Therefore, the inclusion ability of the cavity of the current glycoclusters was initially tested with a typical guest molecule, p-tert-butylbenzoic acid, which is known to form strong inclusion complexes with β-CD in solution 21 (K assoc ≥ 10 4 M -1 ) and in the crystalline state. 22 In addition, this guest molecule lacks NMR signals in the carbohydrate region (5-2.5 ppm).…”