Multivalent presentation

The retention of potent enzyme inhibition and in vitro antiviral activity in the presence of functionalisation with relatively long hydrophobic chains at C-7 of zanamivir has been exploited in the development of di- and poly-valent structmes carrying zanamivir (reviewed in Sun 2007). Multivalent presentation of drug may... 

Synthetic aspects for access to monovalent fullerene-carbohydrate hybrids were highlighted, but only a few biological applications were mentioned. In contrast, multivalent presentation of saccharides by multiple anchorages to the same structure, or their presentation as antennary glycodendrons, has generated promising results. 

From NPOEs to the Preparation of Clycolipids for Multivalent Presentation... 

NPOEs have been employed in a straightforward route for the preparation of multivalent presentations of the trimannan array present at the distal end of... 

The versatility of NPGs has been further enhanced by chemical modifications of the pent-4-enyl moiety itself. In this context, the pentenyl moiety has been transformed in many spacer functionalities [149,150], used as a handle to incorporate amino-acid moieties [151,152,153, 154], used as a monomer in copolymerization strategies [155,156,157], used in the formation of dendrimers [158], and converted to dimeric and trimeric structures for multivalent presentations [159,160]. These applications fall beyond the scope of this chapter. 

J. Lu, B. Fraser-Reid, and C. Gowda, A strategy for ready preparation of glycolipids for multivalent presentation, Org. Lett., 7 (2005) 3841-3843. 

Naturally occurring carbohydrate multivalent displays are widespread in nature and include mucins, pathogen, and mammalian cell surfaces. Lectins, carbohydrate-binding proteins, often present multiple repeat carbohydrate binding domains. The interaction of multivalent presentations can result in the formation of numerous simultaneous non-co-valent bonds that proceed to afford the observed high avidity of carbohydrates (153). 

An additional problem with multivalent presenting molecules is that by their very nature they are high molecular weight molecules. Divalent and trivalent compoundscould have low enough molecular weights (less than a 1000 Da) to be orally active. 

S. A. Svarovsky, Z. Szekely, and J. J. Barchi, Synthesis of gold nanoparticles bearing the Thomsen-Friedenreich disaccharide A new multivalent presentation of an important tumor antigen, Tetrahedron Asymmetry, 16 (2005) 587-598. 

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