Chapter 27 - Amines, Amino Acids, and Polymers Flashcards
What are amines derived from?
Derivatives of ammonia with one or more H’s replaced by carbon chain/ring
How are amines classified?
They are classified as primary, secondary, or tertiary depending on the number of alkyl groups or aryl groups attached to the nitrogen atom
What is serotonin, and what functions does it control?
Serotonin is a neurotransmitter that controls appetite, sleep, memory, learning, and temperature regulation
What is pseudoephedrine used for and how does it work?
Pseudoephedrine is an active ingredient in decongestant medicines. It works by shrinking nasal membrane and inhibiting nasal secretion
How do you name a primary amine when the NH2 group is at the end of the chain?
Use the suffix -amine (e.g. butanamine)
How do you name a primary amine when the NH2 group is not at the end of a chain?
Use the prefix amino- with a number to indicate the position (e.g. 2-aminobutane)
How are secondary or tertiary amines with different alkyl groups named?
Use the prefixes di- or tri- to indicate the number of identical groups (e.g. dimethylamine)
How are secondary or tertiary amines with different alkyl groups named?
They are named as N-substituted derivatives of the larger group (e.g. N-ethyl-N-methylpropylamine)
What are putrescine and cadaverine, and how are they related to amines?
They are foul-smelling amines produced from the breakdown of proteins in decomposing organsisms
How do amines behave as bases?
The lone pair on the nitrogen atom can accept a proton, forming a dative covalent bond
What is the general formula for α-amino acids?
RCH(NH2)COOH - all common amino acids in the human body are α-amino acids
Where is the amino group located in less common amino acids?
In less common amino acids, the NH2 groups is connected to the β (3rd) or γ (4th) carbon
What functional groups do amino acids contain and how do they react?
They contain the acidic COOH group and a basic NH2 group, so they react similarly to carboxylic acids and amines
How are amides classified?
Amides can be primary, secondary or tertiary (general structure: R-CONHR)
What is required for optical isomerism to occur?
A chiral centre - a carbon atom bonded to four different atoms or groups of atoms
What are optical isomers?
Non-superimposable mirror images; two exist per chiral centre
Which biological molecules commonly contain chiral carbon atoms?
Sugars, proteins, nucleic acids, and all α-amino acids except glycine
How is a chiral carbon represented and how are optical isomers drawn?
Chiral carbons are shown with an asterisk * and isomers are drawn using a 3D tetrahedral arrangement
Why are optical isomers significant in biological systems?
They react differently with receptors, causing different taste or smell sensations
What is condensation polymerisation?
The joining of two monomers with the loss of a small molecule, usually water
What are poly(lactic acid) and poly(glycolic acid) used for?
They are biodegradable polymers used as dissolvable stitches
Why is lactic acid considered more sustainable?
Because it is derived from maize, a renewable resource
What is Terylene and where is it usef?
Terylene is a polyester used in plastics and clothing
What is another use of polyesters besides clothing and plastics?
They can also be used as electrical insulation
