A new glycosidation method through nitrite displacement on substituted nitrobenzenes
Xavier Alvarez-Micó1, Mario J F Calvete, Michael Hanack
1Institute of Organic Chemistry, University of Tuebingen, Auf der Morgenstelle 18, 72076 Tuebingen, Germany.
Carbohydrate Research
|December 22, 2006
Summary
Researchers synthesized aryl glycosides from protected sugars and activated nitrobenzenes. This method yields useful dicyanophenyl glycosides, key building blocks for creating phthalocyanine-glycoconjugates through template synthesis.
Area of Science:
- Carbohydrate Chemistry
- Organic Synthesis
- Glycoconjugate Chemistry
Background:
- Aryl glycosides are important in medicinal chemistry and materials science.
- Efficient synthesis of specific glycosidic linkages remains a challenge.
Purpose of the Study:
- To develop a versatile method for synthesizing aryl glycosides.
- To prepare dicyanophenyl glycosides as precursors for phthalocyanine-glycoconjugates.
Main Methods:
- Reaction of protected 1-OH and 1-SH glycoses (glucose, glucosamine, galactose, mannose, lactose series) with activated nitrobenzenes.
- Utilizing nucleophilic aromatic substitution (S(N)Ar) reactions.
Main Results:
- Achieved 50-100% yield of aryl glycosides.
- 1-OH glycoses yielded predominantly alpha-glycosides via reversible S(N)Ar.
- 1-SH glycoses afforded exclusively beta-glycosides without anomerization.
Conclusions:
- Developed a reliable method for aryl glycoside synthesis.
- Prepared dicyanophenyl glycosides are valuable intermediates for phthalocyanine-glycoconjugate synthesis.
- The stereochemical outcome is controllable based on the glycosyl donor (1-OH vs. 1-SH).
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