Review for Exam 2
Carbohydrates – Monosaccharides
- Aldose vs ketose – know definition and names of and be able to recognize
the general formulas of aldoses and ketoses in straight chain and ring
An Aldose has a CHO group at the end and a ketose has a CH2OHC=O at the end.
anomeric carbon in an aldose is C1; in a ketose, it is C2.
- Triose, tetrose, pentose, vs. hexose – know the definitions and names of
These indicate the number of carbons in a sugar.
A triose has 3 carbons; a tetrose has 4;
Monosaccharide ID in straight chain form for aldopentoses, aldohexoses,
ketopentoses, and ketohexoses
Aldohexoses: All Altruists Gladly Make Gum in Gallon Tanks (Allose, altrose, glucose,
mannose, gulose, idose, galactose, talose)
Aldopentoses: Rabid Arabs Xylophone Linked (Ribose, Arabinose, Xylose, Lyxose)
Ketohexoses: Psychotic Profs Fry Sorbid Students with Tagalong Tests (Pscicose,
fructose, sorbose, tagatose)
Ketopentoses: Ribulose, Xylulose
Epimer – definition of epimer and know the names of the C#2, C#3, and C#4
epimers of D-Glu
An epimer is a compound that differs from another only at one chiral center, rather than all, as in
C2 epimer of glucose: Mannose; C3: Allose; C4: Galactose
Anomer – know the definitions of anomers, anomerization, anomeric
Anomers are a special type of epimer that differ at the anomeric carbon.
distinctive in that a Carbon is MADE chiral as a result of anomerization, whereas an
epimer’s chiral Carbon was already chiral to begin with.
They are the reason that there
are alpha and beta configurations of sugars.
Anomerization is the reaction that results in
anomers from straight chain sugars.
The anomeric carbon in an aldose is C1; in a ketose,
it is C2.
Fisher projection formula -
, D- vs L-, pyranose vs furanose – be
able to go from straight chain to Fisher projection formula; be able to