VOL. 8, NO.7
SUGAR CONFIGURATIONS
1369
A NUMBER SYSTEM FOR SUGAR CONFIGURATIONS Lours SATTLER, BROOKLYN COLLEGE, BROOKLYN, NEWYORK The use of symbols for representing the configurations of sugars has been suggested by a number of writers. The following method has been found to be an excellent aid to the memory. I t is applicable to the systems suggested by others. For example, if we represent C==O or HW group by an arrowhead 4, the straight carbon chain by a vertical l i e , the hydroxyl groups by short horizontal bars, and the HzCOH group by small circles, glucose H-C=O I
H-c-OH I
HO--C-H
I
H-?-OH
may then be pictured as
-
.
If we adopt the convention
d - O H
of writing the aldehyde group on top and then count the number of hydroxyl groups occuring together on one side before we come to the hydroxyl 4. -1
groups on the other, we find for glucose 1-1 and then 2. For mannose
4. I-
it is 2-2, and for galactose
b
or 1-2-1.
Hence, we can recall very readily the configuration of glucose by merely remembering the number 112, of mannose by 22, of galactose by 121. This mnemonic method may be readily extended to other sugar types. 0
-?
Fructose, for example, would be resenting the CH20HC0 group.
-
its mnemonic 12', the prime rep-