1. AMIDES

2. Structure and Properties
Contain the peptide or amide linkage as their functional group.
Structurally similar to esters.
Amide linkage is very significant in biological
systems as the forming and breaking of these bonds
give specificity to proteins.

3. Preparation
Amides are made through a condensation reaction of a carboxylic acid and a primary or secondary amine.
Tertiary amines can not be used as they do not contain a hydrogen.

4. Naming Amides The name of an amide is similar to that of an ester.
The name consists of 2 parts.
1. Derived from the amine (drop the amino).
2. Derived from the acid. Remove the “oic acid” and replace it with amide.

5. Amino Acids
Amino acids are bifunctional because they contain both an amino group (NH2) and a carboxyl group (COOH).
Depending on what they are mixed with, amino acids can act as either an acid or a base.
The amino and carboxyl groups are attached to the same carbon ( carbon).
The 20 different amino acids only differ in their side chains (R group).

6. Amino acids are the building blocks of proteins.
Amino acids join together to form peptides through condensation reactions.
When 2 amino acids undergo a condensation reaction, a DIPEPTIDE is formed.

7. POLYPEPTIDES may be formed by stringing a number of amino acids together through peptide linkages.
Polypeptides with characteristic amino acid sequences are specific proteins.
The side chain on the amino acids will determine the interactions that occur within the protein, giving it a 3 dimensional shape essential for proper protein function.
Proteins are used as structural building blocks (muscle, hair), enzymes (biological catalysts) and hormones (i.e. insulin)