Novel Amphiphilic Cyclodextrins: Graft-Synthesis of Heptakis(6-alkylthio-6-deoxy)-β-cyclodextrin 2-Oligo(ethylene glycol) Conjugates and Their ω-Halo Derivatives

Abstract

Novel amphiphilic cyclodextrins were synthesised by grafting oligo(ethylene glycol) units onto the secondary side of heptakis(6-alkylthio-6-deoxy)-β-cyclodextrins (alkyl = ethyl, hexyl, dodecyl and hexadecyl). The oligo(ethylene glycol) substituents were introduced by reaction of heptakis(6-alkylthio-6-deoxy)-β-cyclodextrins with ethylene carbonate in the presence of potassium carbonate at elevated temperatures. The resulting oligo(ethylene glycol)-cyclodextrin conjugates were characterised by 1 H NMR and 13 C NMR, COSY and HSQC spectroscopy, and mass spectrometry. Addition of

Intravesicular and intervesicular interaction by orthogonal multivalent host–guest and metal–ligand complexation

“…The synthesis of L was described previously (46). The synthesis of the amphiphilic CD1 and the preparation of unilamellar vesicles of CD1 have also been described (41,42,44). The preparation of ␤CD SAMs on gold substrates was described in detail previously (50).…”

“…Our model system is based on the multivalent inclusion binding of a coordination complex at the surface of ␤-cyclodextrin (␤CD) host vesicles. Previously we reported the preparation of amphiphilic ␣-, ␤-, and ␥-CDs and the corresponding bilayer vesicles, which have the ability to recognize and bind guests by size-selective inclusion in the CD host cavities at the vesicle surface (41)(42)(43)(44)(45). We also recently described the multivalent interaction of the Cu(II) and Ni(II) complexes of adamantyl (Ad)-functionalized ethylenediamine (en) L to a SAM of ␤CD molecules (46).…”

Amphiphilic Cyclodextrins as Nanocarriers of Genistein: A Spectroscopic Investigation Pointing Out the Structural Properties of the Host/Drug Complex System

“…A strategy to improve its rate of absorption and to achieve a rapid onset of activity consists in the encapsulation in nanocarriers of ACyDs. It has been shown that specially designed novel classes of amphiphilic b-CyDs are versatile guest encapsulators due to their capability to form micelles, nanoaggregates, 13,15 or vesicles. [12][13][14]26,34 The main peculiarity emerging from this study is the capacity of Gen to interact with SC6OH forming a stable nanosystem prepared with emulsificationdiffusion method.…”

“…11 In the recent past, some of us demonstrated that amphiphilic b-CyDs grafted with oligoethylene glycol moieties [12][13][14] are capable of forming nanoaggregates (micelles, micellar aggregates, or vesicles) 15,16 of potentially low immunogenicity according to the hydrophobic-hydrophilic balance. ACyDs are good candidates for encapsulating molecules more efficiently than a single CyD 16 and for delivering a photosensitizer drug into cancer cells [17][18][19] since there is superior guest molecule retention by these aggregates.…”

Amphiphilic Cyclodextrins, Synthesis, Utilities and Application of Molecular Modeling in Their Design

“…The first Amphiphilic CD to form bilayer vesicles were reported by Ravoo and Darcy in 2000 Mazzaglia et al, 2001;Falvey et al, 2005). Synthesis of them initiated from per-6-bromo and at the result of nucleophilic substituation with the sodium or potassium salt of alkyl thiols, per-alkyl thio CDs were prepared then hydroxyl groups that bind to C-2 of these compounds reacted with an excess of ethylene carbonat and finally average of two units of ethylene glycol were located in this position (C-2 of the CD) Mazzaglia et al, 2001 ) (Fig.…”