A cyclomaltooligosaccharide containing seven R-(1f4)-D-glucopyranosyl units ( -cyclodextrins) was transformed into heptakis 6-deoxy-6-iodo (13) and heptakis 6-amino-6-deoxy (25) derivatives using known procedures. Compound 13 was peracetylated and condensed in one pot with the known peracetylated pseudothiouronium salts of -D-glucopyranose (4), -D-galactopyranose (5), or -D-N-acetylglucopyranosylsamine (6) or with R-D-1-deoxy-1-thiomannopyranose (8) using cesium carbonate in dimethylformamide. Alternatively, peracetylated 4-aminophenyl-R-D-mannopyranoside (9) was transformed into either extended pseudothiouronium 11 following N-chloroacetylation and nucleophilic substitution by thiourea or into 4-isothiocyanatophenyl R-D-mannopyranoside 12 using thiophosgene. Each of the four thiolated sugar derivatives 4-6 or 8 were also coupled to heptakis chloroacetamido -CD 26 obtained from heptakis amine 25 after N-chloroacetylation. Further incorporation of a hexamethylenediamine spacer arm onto heptakis iodo -CD 13 using thiol derived from mono-Boc derivative 36 and coupling to isothiocyanate 12 after suitable deprotection afforded permannosylated derivative 38. Zemplén de-O-acetylation of all -CD derivatives provided watersoluble persubstituted compounds containing D-glucopyranosides (18, 30), D-galactopyranosides (19, 31), D-N-acetylglucosaminides (20, 32), and D-mannopyranosides (22, 24, 34, 39), respectively. The compounds were then evaluated for their relative binding properties toward natural carbohydrate binding plant lectins using both microtiter plate competitive inhibition experiments, double sandwich assays using horseradish peroxidase labeled lectins and by turbidimetric assays. The plant lectins from Pisum sativum (pea), Arachis hypogea (peanut), Canavalia ensiformis (Concanavalin A), and Triticum vulgaris (WGA, wheat germ agglutinin) were used for -D-glucose, -D-galactose, R-Dmannose, and -D-N-acetylglucosamine, respectively. All persubstituted -CDs showed good to excellent inhibitory properties together with abilities to cross-link their analogous plant lectins. The capacity of perglycosylated -CDs to anchor both microtiter plate-coated lectins and their corresponding peroxidase-labeled derivatives further confirmed the usefulness of these multivalent neoglycoconjugates in bioanalytical assays.

A convenient method for the synthesis of b-d-gluco-, b-d-galacto-, 2-acetamido-2-deoxy-b-d-gluco-and ad-mannopyranosylamine clusters based on cyclomaltoheptaose (b-cyclodextrin) is presented. The synthesis involves: 1) the one-pot synthesis of the acetylated chloroacetyl N-glycoside derivatives of d-glucose, d-galactose, 2-acetamido-2-deoxy-d-glucose and d-mannose from the corresponding glycosyl azides, 2) conversion of the chloroacetyl N-glycosides into their isothiouronium derivatives, then 3) attachment of the Nglycosides onto heptakis(6-deoxy-6-iodo) and heptakis(6-chloroacetamido-6-deoxy) b-cyclodextrin by means of nucleophilic displacement with caesium carbonate in dimethylformamide, and 4) de-O-acetylation of b-cyclodextrin derivatives. The chloroacetyl N-glycoside derivatives were easily prepared by mild reduction of the azide function by one of two methods: a) by the Staudinger reaction, with nBu 3 P, and b) with 1,3-propanedithiol, as reducing reagents.

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