Synthesis of Oligomeric Mannosides and Their Structure-Binding Relationship with Concanavalin A

• Published in: Chemistry, an Asian journal an Asian journal, 2014-07, Vol.9 (7), p.1786-1796
• Main Authors: Li, Chen-Wei, Hon, Kai-Wei, Ghosh, Bhaswati, Li, Po-Han, Lin, Hsien-Ya, Chan, Po-Han, Lin, Chun-Hung, Chen, Yu-Chie, Mong, Kwok-Kong Tony
• Format: Article
• Language: English
• Subjects: Binding Sites; carbohydrates; Chemical Precipitation; Chemistry Techniques, Synthetic; Concanavalin A - chemistry; Concanavalin A - metabolism; dendrimers; Fluorescein - chemistry; Fluorescein - metabolism; Fluorescence Polarization; glycopeptides; Mannosides - chemical synthesis; Mannosides - chemistry; Mannosides - metabolism; multivalent effect; precipitation; Scattering, Radiation; Structure-Activity Relationship; Thermodynamics
• ISSN: 1861-4728; 1861-471X
• DOI: 10.1002/asia.201402029

Small glycodendrimers with α‐mannosyl ligands were synthesized by using copper‐catalyzed azide–alkyne coupling chemistry and some of these molecules were used as multivalent ligands to study the induction of concanavalin A (Con A) precipitation. The results showed that the monovalent mannose ligand could induce the precipitation of Con A. This unexpected finding initiated a series of studies to characterize the molecular basis of the ligand–lectin interaction. The atypical precipitation is found to be specific to the mannose, fluorescein moiety (FITC), and Con A. Apparently the mannose ligand binds to Con A through hydrogen‐bonding interactions, whereas the binding of FITC is mediated by hydrophobic forces. Being precipitate: A series of glycodendrimers with α‐mannosyl ligands were prepared and used to explore the precipitation of concanavalin A (Con A). Surprisingly, the monovalent mannose ligand induced Con A precipitation, which led to an investigation of the molecular basis of the ligand–lectin interaction (see figure).