Synthesis of N-acetylglucosamine derivatives as probes for specificity of chicken hepatic lectin.
Syntheses of the following compounds are described: 6-(Trifluoroacetylamino)hexyl 2-acetamido-2,6-dideoxy-beta-D-glucopyranoside and 2-acetamido-2-deoxy-alpha-D-xylopyranoside, two allyl 2-acetamido-2-deoxy-alpha-D-glucopyranosiduronic acid derivatives, and several allyl 2-acylamido-2-deoxy-beta-D-glucopyranosides having different acyl groups. These and other compounds were used as inhibitors in the binding assay for the chicken hepatic lectin specific for N-acetylglucosamine. We found that: 1) The inhibitory potency of N-acylglucosamine derivatives decreased progressively with increase in the size of acyl group, 2) absence of either 3- or 4-OH group of N-acetylglucosamine lowered the binding affinity more than 100-fold, and 3) the presence of a negatively charged group (carboxylic acid) at the C-6 position did not lower the affinity. The first two items are similar to the mammalian hepatic galactose/N-acetylgalactosamine lectins, but the last item is in a strong contrast to the mammalian lectins.
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