Kojibiose is a reducing sugar that forms D-glucose on hydrolysis with aqueous acid. Reaction of kojibiose with iodomethane and Ag20 yields an octamethyl derivative, which can be hydrolyzed with aqueous acid to give one equivalent of 2,3,4,6-tetra-O- methyl-D-glucopyranose and one equivalent of 3,4,6-tri-O-methyl-D-glucopyranose. If kojibiose is hydrolyzed by alpha-glucosidases but not beta-glucosidases, what is its structure?

Kojibiose is a reducing sugar that forms D-glucose on hydrolysis with aqueous acid. Reaction of kojibiose with iodomethane and Ag20 yields an octamethyl derivative, which can be hydrolyzed with aqueous acid to give one equivalent of 2,3,4,6-tetra-O- methyl-D-glucopyranose and one equivalent of 3,4,6-tri-O-methyl-D-glucopyranose. If kojibiose is hydrolyzed by alpha-glucosidases but not beta-glucosidases, what is its structure?

Organic Chemistry

8th Edition

ISBN:9781305580350

Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Publisher:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. Foote

Chapter25: Carbohydrates

Section: Chapter Questions

Problem 25.29P

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