Dendrimer carbohydrate-based

Common core structures are aromatic systems (Fig. 12), e.g. derivatives of trisubsti-tuted benzene [70], These can in turn be extended either by functionalized aromatic systems or by other functionalized linkers, e.g. carbohydrate-based spacers [119] or additional monosaccharides, e.g. furanoside derivatives [120], A similar architecture has been employed for anthracene capped chiral dendrimers [112, 121],... 

Polyplexes are formed from many cationic polymers such as histones, PEI, dendrimers (pDMAEM) or carbohydrate-based polymers such as chitosan and cyclodextrin. Polyplexes are smaller in size than lipoplexes, which is a major physicochemical property for gene delivery, especially in vivoJ... 

Narain R (ed) (2011) Engineered carbohydrate-based materials for biomedical applications-Polymers, surfaces, dendrimers, nanoparticles, and hydrogels. Wiley, Hoboken... 

This review is devoted to the description of synthetic strategies for glycodendrimers synthesis. Dendrimers can be classified into three categories carbohydrate-coated, carbohydrate-centered and carbohydrate-based dendrimer. In this paper we will focus on the third one, in which the core unit is originated from a monosaccharide. Compare to classical Pamam, Boltorn cores, carbohydrate units add much more three dimension information, coded in the chirality in almost each carbon. Various coupling chemistry have been developed and are presented here glycosylation, amide bound formation, and click chemistry (thiol-ene reaction, epoxide - thiol reaction). 

Fig. 1 Carbohydrates in dendrimers Carbohydrate-coated (a), carbohydrate-centered (b) and carbohydrate-based (c).

M. Ehara, Carhohydrate-derived hydrogels and microgels, in R. Narain, ed.. Engineered Carbohydrate-Based Materials for Biomedical Applications Polymers, Surfaces, Dendrimers, Nanoparticles, and Ely dr o gels, Wiley, Hoboken, NJ, 2011. 

M. Dubber and T. K. Lindhorst, Trehalose-based octopus glycosides for the synthesis of carbohydrate-centered PAMAM dendrimers and thiourea-bridged glycoclusters, Org. Lett., 3 (2001) 4019 1022. 

As shown below in Section 4.1.9 (silicon-based dendrimers), there are meanwhile many examples of carbohydrate-coated dendrimers (glycodendrimers) [48], not least because these terminal groups confer better solubility upon the molecules because they are, so-to-speak, sugar coated . 

Glyco-coated dendrimers possess a core structure of varied chemical nature, with a number of peripheral groups to which carbohydrate moieties are attached. The most common core structures are based on polyaminoamides (PAMAM) or poly(propyleneimine) (Astramol ) with a primary amine at the periphery, and these are commercially available. Polyamides based on N,N-bis(3-aminopropyl)glycine and A,Ar-bis(3-aminopropyl)succinic acid have also been prepared.78... 

FIGURE 16.2 Molecular structures of different glycodendrimers. (a) A carbohydrate-coated dendrimer with 24 pendant monosaccharide residues, (b) A carbohydrate-centered dendrimer with a p-cyclodextrin ((3CD) core and 14 copies of a glycosyl thiol residue, (c) A (1-D-glucosamine-based glycodendrimer comprising 16 monosaccharide residues arranged around a tetravalent polyphenylene core. 

Applications of click chemistry are already far too numerous to acknowledge by even offering an example fi om each area herein. Some of these areas include dendrimers, polypeptides, polymeric materials, conformationally restricted macrocycles, new ligand designs, and carbohydrates. One representative procedure is provided below. A related study describes sugar-based silica gels for use as hydrophilic interaction chromatography (HILIC) for separation of monosaccharides. ... 

C-branched dendritic structures, based on either ether and amide linkages or simply amide connectivity (iii) Tomalia-type PAMAM dendritic structure, differing from the POPAM by the presence of amide bonds, but keeping the amine AB2 as the branching center and (iv) Fr6chet-type dendritic strnctures, based on ether and phenyl groups as AB2 branching center. Description of the different types of covalent dendrimers reported will follow a classification based on the element content, such as only C, C-N, N-O, C-N-0, or with heteroatoms such as P, Si, and so on. Examples of porphyrin-, thiophene-, carbohydrate-, and fullerene-based dendrimers are described separately, since they can be bound to different types of frameworks. 

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