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Please bring any extra or unwanted canned food items you have in your dorm rooms to class so that I can donate them to the Caritas House

Click here for a copy of the mechanism sheet used in lecture today.

Rules of the Day 4-30-08

1. Carbohydrate monomers can be linked together via acetal bonds, and this linkage can be alpha or beta. (For glucose, alpha is axial) This type of acetal bond is called a glycosidic bond and is named as alpha or beta referring to the stereochemistry of the anomeric carbon and also by the numbers of the ring carbons attached via the -C-O-C- linkage (i.e. alpha 1,4-). Click here for a third molecule of the day that discusses much of this.

2. Sucrose is glucose linked to fructose.

3. Other atoms besides O can take part in glycosidic bonds, for example N. Imoprtant molecules with N-glycosidic bonds include the nucleic acids.

4. Cells in our bodies have complex patterns of carbohydrates on their surfaces, and we are only now learing about these structures and how they function. Blood group markers are good examples of this that you may be familiar with.

5. Both starch and cellulose are polymers of glucose, but starch has the alpha (axial) glucose linkages so it is bent and therefore not rigid (potatoes). Cellulose has the glucose monomers linked via beta(equatorial) glucose linkages so it is flat and the chains can pack together nicely to create rigid cellulose (wood). Click here for a molecule of the day that discusses most of this.

6. Many syntheses are carried out with a starting material reversibly attached to beads. This has the advantage of allowing exchange of reagents and isolation of products by simple filtration. This process can be automated, allowing the synthesis of even complex molecules like DNA, RNA, and proteins by machine. This also allows synthesis of hundreds of molecules in parallel, speeding up the drug discovery process.

Homework: Here is a practice aromatic reactions and synthesis homework. Click here to download a pdf file. You will NOT turn this in, but we have posted answers, click here for the answers. It is here as a tool to get you ready for the aromatic reactions portion of the final. Click here for the last (10th) homework set. You will turn this in Friday, May 2.

Great White Shark Attack near San Diego!!!