Lecture 19 Flashcards
Constitutional Isomer
order of atoms changes
tautomers
Fischer Projections
Drawing monosaccharides
carbon numbering begins at carbonyl end of aldose
Stereoisomers
same connectivity but different spatial organization
Configurational Isomers
chiral carbons
enantiomers and diastereomers
Enantiomers
mirror images at all chiral centers
Diastereomers
have multiple chiral centers
are not mirror images
Haworth Projections
cyclical version of carbohydrates
can convert fischer to haworth
Anomers
differ only at the anomeric C (carbonyl carbon, directly connected to O in ring)
Epimers
differ at any carbon other than the anomeric carbon
Conformational isomers
reversible rotational changes
Glyceraldehyde
Triose, aldose two carbons not on C=O
Ribose
Pentose, aldose, 4 carbons not on C=O
Glucose
Hexose, aldose, 5 C not C=O and middle C has OH to the right
Galactose
Hexose, aldose, 5 C not C=O and middle C has OH to the left
Dihydroxyacetone
Triose, Ketose, middle C is C=O
Ribulose
Pentose, Ketose, Second C is C=O
Fructose
Hexose, Ketose, second C is C=O
Glycosides are formed when:
one or more hydroxyls are replaced
5 ways to replace a hydroxyl to form a Glycoside
Fucose, Ester (phosphorylation), RedOx (alcohol), N-linkages (Amino sugars and nucleotides), O-linakges (methylation or toxins)
Regular monosaccharides
D-Glucose
D-Galactose
D-Mannose
D-Xylose
Oddball Monosaccharide
L- fucose
Excess in blood indicates liver damage, cancer, diabetes, heart disease
Only L made or used by animals
Amino Sugars
GlcNAc
GalNAc
Sialic Acid
Roles of Polysaccharides
Glucose Storage, structure, protein diversity
Glucose Storage
alpha linkages
