Chapter 8 (part2) Carbohydrates: oligo- and polysaccharides

Chapter 8 (part2)

Carbohydrates: oligo- and polysaccharides

Glycosidic Linkage

O

CH2OH

OH

OH

OHOH

O

CH2OH

OH

OH

OH

OH

H2OH2O

O

CH2OH

OH

OH

OH

O

O

CH2OH

OH

OH

OH

alcohol

hemiacetal

glycosidic linkage

Hydrolysis

Condensation

acetal

DisaccharidesO

CH2OH

OH

OH

OH

O

O

CH2OH

OH

OH

OHH

H

H

H

H

H

H H

O

CH2OH

OH

OH

OH

O

O

CH2OH

OH

OH

OH

H

H

H

H

H

H

H

H

O

CH2OH

OH

OH

H

O

O

CH2OH

OH

OH

OH

H

OH

H

H

H

H

H

H

maltose cellobiose

lactose

sucrose

-D-glucosyl-(1->4)--D-glucopyranose)

-D-glucosyl-(1->4)--D-glucopyranose)

-D-galactosyl-(1->4)--D-glucopyranose)

-D-glucosyl-(1->2)--D-fructofuranose)

O

CH2OH

OH

OH

OH

H

H

H

H

OCH2OH

H

H

OH

OH

H

O

CH2OH

Higher Oligosaccharides

Oligosaccharide groups are incorporated in to many drug

structures

Polysaccharides

Amylose and Amylopectin

Iodine binding to starch

glycogen

Dextrans

Cellulose

Cellulose vs Amylose

Glucose units rotated 180o relative to next residue

cellulose

amylose

Cellulose

Chitin

Chitin vs Cellulose

Glycoproteins

O-linked Glycoproteins

Blood ABO Antigens

Structure of the ABO blood group carbohydrates,

R represents the linkage to protein in the secreted forms, sphingolipid in the cell-surface

bound formopen square = GlcNAc, open diamond = galactose, filled

square = fucose, filled diamond = GalNAc, filled diamond = sialic

acid (NANA)

N-linked Glycoproteins