Platform Synthetic Lectins for Divalent Carbohydrate Recognition in Water

Area of Science:

• Carbohydrate chemistry
• Supramolecular chemistry
• Biomaterials

Background:

• Biomimetic carbohydrate receptors, or synthetic lectins, are valuable tools in biological research and medicine.
• Current synthetic lectins are limited in recognizing various saccharide types under aqueous conditions, especially non-equatorial carbohydrates.

Purpose of the Study:

• To develop novel synthetic lectins capable of recognizing a broader range of carbohydrates in aqueous environments.
• To mimic the multivalency and binding characteristics of natural lectins.

Main Methods:

• Design and synthesis of a pyrene-based platform with polar arches on aryl substituents.
• Incorporation of dual binding sites to achieve multivalency.
• Testing receptor compatibility with axially substituted carbohydrates.
• Characterization of binding affinities for aminosugars and α-sialyl units using variants with charged functionalities.

Main Results:

• Developed synthetic lectins compatible with axially substituted carbohydrates.
• Demonstrated multivalency through identical binding sites.
• A negatively charged receptor variant formed 1:2 host/guest complexes with aminosugars, showing high affinity (K1 >3000 M⁻¹) for mannosamine.
• A positively charged variant effectively bound the α-sialyl unit (K1 ≈1300 M⁻¹).

Conclusions:

• The new pyrene-based receptors offer a versatile platform for recognizing diverse carbohydrate structures, including challenging axially substituted ones.
• These synthetic lectins effectively mimic natural lectin multivalency and binding properties.
• The developed receptors hold significant potential for advancing biological research and therapeutic applications in glycobiology.