Biomolecules, Volume 2

Nucleic acids and amino acids. What a pair. Today's lecture dealt with the two classes of compounds mentioned above, with some commentary on how they can be strung together to form larger biomolecules. With nucleic acids, it was the recognition of the 3' - 5' coupling; the resultant macro structure is held together in helical form largely by non-covalent forces (in this case, hydrogen bonds). As for amino acids, we saw how they exist in zwitterionic form in aqueous solution. There are a variety of different types of side chains that can be attached which can be broken up into the generic catagories of neutral, acidic, and basic.

Chains of amino acids make peptides, many enzymes and proteins are nothing other than amino acids. The overall structure can be described as primary (1°, the order of amino acids), secondary (2°, local interactions such as helices, sheets and turns), and tertiary (3°, the complete three-dimensional structure).

The picture, as promised, is from Kill Bill, Volume 2.

Biomolecules, Volume 1

Today we talked about lipids and carbohydrates. There wasn't a lot of exciting information but you should be able to identify various types of biomolecules and you should be able to show an understanding of carbohydrates (simple/complex, aldose/ketose, D/L, etc.). I have posted a copy of last year's exam #1 (on the right).

The picture, of course, is from Kill Bill, Volume 1.

Useful chapter 2 questions: 1, 3, 4, 6, 7, 8, 10, 15, 16, 20

Stereocenters

Today was a day to go over a lot of material regarding stereocenters. We covered everything from standard (R) and (S) configurations to enantiomers and diastereomers. Most of the class was spent trying to figure out how to separate a pair of enantiomers; in the end we came up with the idea of adding a second stereocenter of known configuration in order to make a pair of diastereomers and then separating those.

New topics dealt with prochirality, the concept of atoms that could be stereocenters if we did something to them. There are two kinds: Faces, which are termed re and si, depending on the orientation of substituents according to CIP rules; and pro-R/pro-S, in which we decide what stereochemistry an atom would have IF we made a change to one of the substituents (typically, converting an H to a D).

The picture shows si and re faces of F420 and NADPH. We will learn about such things soon!

Mechanisms, Sweet Mechanisms

Today we looked at lots of mechanisms from organic. It was pretty much a review of things you already knew (or knew at one time) with a few comments on how these reactions could come into play in bioorganic chemistry.

Friday will start Chapter 2 with an emphasis on stereochemistry.

First Day!

A pretty easy first day of class -- background information, a review of the syllabus and semester grid, and a brief look at functional groups. On Wednesday we'll get into a review of organic mechanisms. In the meantime, some useful questions for the end of chapter one: 1, 3, 4, 5, 6, 7, 8a, 8b, 13

We also took the class picture. A handsome group of students!

Welcome!

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