Download OH and

THE RING STRUCTURE
of -D glucose
CH2OH
CH(OH)
C OH
HO-C
C OH
O
C
CH2OH
C
O
C OH C
HO C - C
OH
FISCHER TO HAWORTH
Anomeric
Carbon
C-1
CARBOHYDRATES
-D-Glucose
Projections
HO
4
HO
H
CH2OH
5
O
3
H
OH
Haworth
2
1
Chair
Conformation
HO
E
1
A
A
2
E
E 3
A 4
E 5
CH2OH
-D-glucose is the most stable monosaccharide
-D-glucose is the most abundant
organic compound in nature!
A
E
A
OH
OH
4
CH2OH
5
CH2OH
5
O
3
O
3
4
2
1
2
1
PYRANOSES AND FURANOSES
O
FURAN
PYRAN
CH2OH
CH2OH
O
O
O
1
CH2OH
CH2OH
O OH OH O
1
OH OH
a-D pyranose
a-L pyranose
-D pyranose
-L pyranose
When is it Alpha, When is it Beta?
Rule: In a Haworth projection, when the -OH on the
anomeric carbon is drawn in the same direction as the
CH2OH, its a BETA sugar
Corollary: -OH and –CH2OH in opposite directions for an
ALPHA sugar.
up
up
CH2OH
O OH
up
CH2OH
O
OH
Beta sugar
Alpha sugar
down
When is it D, When is it L?
Rule: A right hand projection with the –CH2OH up is a Dsugar. A left hand with the –CH2OH up is an L-sugar
Right Hand
CH2OH
O
D-sugar
Left Hand
CH2OH
O
L-sugar
Note how an L is the mirror image of a D
Test Your Powers of Observation
CH2OH
CH2OH
O
CH2OH
O OH
OH
a-D
HO
O
O
HO
-D
O OH
CH2OH
CH2OH
a-L
-L
OH
O CH2OH
OH
CH2OH
HO O
CH2OH
O
a-L
a-L
-L
a-D
D- vs L-Glucose
D-glucose
C6H12O6
Crystalline, colorless
Mwt. 180.16
Nutrient
L-glucose
C6H12O6
Crystalline, colorless
Mwt. 180.16
Non-Nutrient
REACTIONS OF MONOSACCHARIDES
1. Reducing sugars
A. Carbonyls (aldehydes and ketones) are easily
oxidized.
2. Isomerization
A. Aldehydes
GLUCOSE
Ketones
FRUCTOSE
a-D GLUCOSE
-D GLUCOSE
MUTAROTATION
REACTIONS (CONTINUED)
3. Esterification (phosphate)
4. Glycoside formation
DERIVATIVES
1. Sugar alcohols
Xylitol = Artificial sweetener
2. Sugar Acids
Aldonic = C-1 Oxidized to -COOH
Uronic = C-6 Oxidized to -COOH
O
C-1 Sugar Acid
C
L - ASCORBIC ACID
HO- C
Vitamin C
HO- C
Lactone
C O
Internal Ester
HO- C
L sugar
CH2OH
ENE-DIOL BOND
St. Gyorgi First to investigate the structure of vitamin C
A carbohydrate
Ignorant of its structure
GODnose
Ignose
Hexauronic Acid
GLYCOSIDES
GLYCOSIDE
GLYCOSIDIC BOND
GLYCOSIDE FORMATION
GLYCOSIDIC BOND
DISACCHARIDES
Anomeric carbon
H
Beta 1-4 glycosidic
bond
CH2OH
CH2OH
O
O
O
OH
D-galactose
D-glucose
Lactose
CH2OH
CH2OH
O
O
O
OH
D-galactose
D-glucose
Lactose
CH2OH
O
CH2OH
O
O
OH
CH2OH
O
CH2OH
O
O
O
D-galactose
D-glucose
Cellobiose
OH
D-glucose (a-1-4) D-glucose
Maltose
D-glucose
(disaccharide of
cellulose)