1. Lecture 37 – Chapter 25 : Carbohydrates
Fischer projections
Cyclic forms – hemiacetal formation, 6 vs. 5
Mutarotation
Glycosides – formation and examples
Disaccharides
Oligosaccharides and Polysaccharides
Miscellaneous reactions

2. Simple monosaccharides – Fischer depictions
D-glucose D-galactose D-glucosamine N-acetyl-D-glucosamine
D-FucNAc D-ManAcA D-Ribose Deoxy-D-ribose

3. Aldohexoses – cyclic forms and their interconversion
All present in solution, free sugars can interconvert

4. Mutarotation dissolve dextrose in water, measure [a]D : +112.2
dissolve b-D-glucopyranose in water, measure [a]D : +18.7
allow either to equilibrate, measure [a]D : +52.5

5. Glycosides Free sugar + alcohol + acid gives a glycoside
Glycosides are no longer free sugars and do not mutarotate

6. Glycosides - disaccharides
Organic synthesis limited by protecting group chemistry needed
Bioorganic enzymatic synthesis now making oligosaccharides

7. Disaccharides – examples

8. Oligosaccharides – examples
Blood group antigens – extremely subtle differences in sugars in the epitope lead to important consequences in blood biochemistry

9. Polysaccharides – examples
amylose
cellulose

10. Synthetic vaccines
Danishefsky et. al. Sloan-Kettering/Columbia – Synthetic vaccine against 3 types of cancer

11. Miscellaneous reactions of free sugars

12. Friday
Chapter 26 – Lipids and fats