An efficient study of carbohydrate-protein interactions was achieved using multivalent glycodendrimer library. Different dendrimers with varied peripheral sugar densities and linkers provided an arsenal of potential novel therapeutic agents that could be useful for better specific action and greater binding affinities against their cognate protein receptors. Highly effective click chemistry represents the basic method used for the synthesis of mannosylated dendrimers. To this end, we used propargylated scaffolds of varying sugar densities ranging from 2 to 18 for the attachment of azido mannopyranoside derivatives using copper catalyzed click cycloaddition. Mannopyranosides with short and pegylated aglycones were used to evaluate their effects on the kinetics of binding. The mannosylated dendrons were built using varied scaffolds toward the accelerated and combined “onion peel” strategy These carbohydrates have been designed to fight E. coli urinary infections, by inhibiting the formation of bacterial biofilms, thus neutralizing the adhesion of FimH type 1 lectin present at the tip of their fimbriae against the natural multiantennary oligomannosides of uroplakin 1a receptors expressed on uroepithelial tissues. Preliminary DLS studies of the mannosylated dendrimers to cross- link the leguminous lectin Con A used as a model showed their high potency as candidates to fight the E. coli adhesion and biofilm formation.

Sponge-like gluco-and thioglycerol-organo-bentonite hosting Cu 0 and Pd 0 subnanoparticles with high affinity towards hydrogen were synthesized through an unprecedented procedure involving a chemical grafting of (3-azidopropyl)triethoxysilane, followed by Cu-catalyzed azide-alkyne cycloaddition with propargyl glucoside or triallyl propargyl pentaerythritol. Further, thioglycerol groups were attached to the alkene groups by photolysis (TEC reaction). This resulted in a structure swelling, but further Cu 0 or Pd 0 nanoparticle incorporation produced a compaction due to strong O:metal and S:metal interactions that improve metal stabilization and prevent re-aggregation. Such a structure favored hydrogen capture via physical condensation with easy release at nearly ambient temperature at the expense of hydrogen dissolution in the metal bulk. This innovative concept opens new prospects for obtaining low cost clay-based matrices for a truly reversible capture of hydrogen.[a] Dr.

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A number of new benzo[h]‐ and benzo[f]chromeno[2,3‐b] pyridine‐5‐ones derivatives were synthesized from benzo[h]‐ and benzo[f]‐chromone‐carbonitriles and amino‐benzo[h]‐ and benzo[f]chromone‐carbaldehydes. © 2006 Wiley Periodicals, Inc. Heteroatom Chem 17:2–7, 2006; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/hc.20152

chromeno[2,3-b]-pyridine-5-ones. -A variety of new derivatives of the title benzochromenopyridine systems is synthesized. The reaction proceeds via condensation of the corresponding benzochromenecarbonitriles (I) with enamines or o-aminobenzochromenecarbaldehydes (VIII) with active methylene compounds. -(ABDEL-RAHMAN*, A.-R. H.; GIRGES, M. M.; EL-AHL, A.-A. S.; SALLAM, L. M.; Heteroat. Chem. 17 (2006) 1, 2-7; Dep. Chem., Fac. Sci., Mansoura Univ., Mansoura 35516, Egypt; Eng.) -M. Kowall 23-157

The syntheses of five propargylated dendrimer scaffolds ranging from 2, 3, 4, 6, and 12 surface groups are described together with a 2-azidoethyl α-D-mannopyranoside. The former is appended to the core structure using highly efficient copper-catalysed azide-alkyne cycloaddition (CuAAC) (“click reaction”) to provide glycodendrimers in an accelerated approach. Two of the core structures are based on cyclotrisphosphazene, thus expanding the scope of the “onion-peel” strategy to build dendritic architectures with a large number of surface groups at the G1 generation only.