CONVERTING FISCHER PROJECTIONS OF “D”
MONOSACCHARIDES INTO HAWORTH STRUCTURES
Fisher projection
O
O
OH
H
H
OH
OH
CH2OH
D-glucose
HO
H
H
O
H
H
H
OH
OH
H
CH2OH
D-glucose
HO
H
H
H
OH
rotate
C4-C5
clockwise
H
H
H
OH
H
OH H
O
rotate
HO
90o clockwise
H
OH H
OH H
OH
D-glucose
OH
H
OH
OH
H
OH
H
CH2OH
H
H
H
H
OH
HO
HO
H
CH2OH
H
*
CH2OH
O H
OH
OH
HOCH2
CH2 OH
H
H
OH H
HO
O
*
H
OH H
O
OH H
OH
alpha-D-glucose
Haworth structure
In the Fischer projection:
1. Carbon-#1 is carbon-#1, the hemiacetal carbon (with a * ), in the
Haworth structure
2. All of the atoms on the right are pointed down in the Haworth structure.
3. All of the atoms on the left are pointed up in the Haworth structure.
4. The CH2OH (the carbon-#6 in D-glucose) is pointed up in the Haworth
structure
5. The OH attached to carbon-#5 (box around it) becomes part of the ring.
6. The linear Fischer projection becomes a cyclic hemiacetal in the Haworth
structure.
In the Haworth Stucture:
1. Carbon-1 “*” is the anomeric carbon
2. The anomeric carbon is derived from the C=O in the Fischer projection.
3. Notice there are no carbonyls in the Haworth projection.
4. The carbonyl has become the hemiacetal group.
Drawing Haworth Projections of D-aldohexoses
1. Draw the Fischer projection and number
the carbon atoms.
D-Galactose
1CHO
H
OH
2
HO
3
H
HO
4
H
H
5
OH
6CH2OH
2. For an aldohexose draw the pyranose
template for the Haworth projection and
number the carbon atom.
6 CH
2OH
5
O
4
D-galactose is an aldohexose, so……..
1
3
3. Add hydroxyl groups to C2 – C4 of the
Haworth template.
A. In the Fisher projection the hydroxyl
groups on the right (only C2) are placed
on a downward bond (a bond below the
ring).
2
6 CH
2OH
5
O
4
1
3
2
OH
6 CH
2OH
B. In the Fisher projection, the hydroxyl
groups on the left (only C3 and C4) are
placed on an upward bond (a bond
above the ring).
HO 5
O
OH
4
1
3
2
OH
4. Add a hydroxyl group to C1 :
6 CH
2 OH
downward for an alpha (α) hydroxyl
(opposite side of ring as the CH2OH)
HO 5
4
O
OH
3
1
2OH
OH
6 CH
2 OH
upward for a beta (β) hydroxyl
(same side of ring as the CH2OH)
HO 5
4
O
OH
OH
3
1
2
OH
FINISHED!
Drawing Haworth Projections of D-aldopentoses
1. Draw the Fischer projection and number
the carbon atoms.
D-xylose
1CHO
H
OH
2
HO
3
H
H
4
OH
5CH2OH
2. For an aldopentose draw the furanose
template for the Haworth projection and
number the carbon atoms.
5 CH2OH
O
4
D-xylose is an aldopentose, so……..
3. Add hydroxyl groups to C2 – C3 of the
Haworth template.
A. In the Fisher projection the hydroxyl
groups on the right (only C2) are placed
on a downward bond (a bond below the
ring).
1
2
3
5 CH2OH
O
4
1
2
3
OH
5 CH2OH
B. In the Fisher projection, the hydroxyl
groups on the left (only C3) are placed
on an upward bond (a bond above the
ring).
O
OH
4
1
2
3
OH
4. Add a hydroxyl group to C1 :
5 CH2OH
downward for an alpha (α) hydroxyl
(opposite side of ring as the CH2OH)
O
4 OH
3
1
2
OH
OH
upward for a beta (β) hydroxyl
(same side of ring as the CH2OH)
5 CH2OH
OH
O
4 OH
3
1
2
OH
FINISHED!
Drawing Haworth Projections of D-ketohexoses
1. Draw the Fischer projection and number
the carbon atoms.
D-fructose
1CH2OH
2
O
HO
3
H
H
4
OH
H
5
OH
CH2OH
6
2. For an ketohexose draw the furanose
template for the Haworth projection and
number the carbon atoms. Notice that
carbon 1 is not present at this point and
the OH at carbon 5 has become part of the
ring.
6 CH2OH
O
2
5
3
4
D-fructose is a ketohexose, so……..
3. Add hydroxyl groups to C3 – C4 of the
Haworth template.
A. In the Fisher projection the hydroxyl
groups on the right (only C4) are placed
on a downward bond (a bond below the
ring).
6 CH2OH
O
2
5
4
3
OH
6 CH2OH
B. In the Fisher projection, the hydroxyl
groups on the left (only C3) are placed
on an upward bond (a bond above the
ring).
O
2
OH
5
4
3
OH
4. Add a hydroxyl group to C2 :
downward for an alpha (α) hydroxyl
(opposite side of ring as the CH2OH)
6 CH2OH
CH OH
O 1 2
HO 2
5
4
OH
upward for a beta (β) hydroxyl
(same side of ring as the CH2OH)
3 OH
6 CH2OH
OH
O
HO 2
5
4
OH
Notice that the carbon-1 CH2OH is placed
opposite the OH at C2
FINISHED!
3
CH2OH
1