Isomerism and Stereochemistry Flashcards
1
Q
Stuctural isomer
A
- Same molecular formula atoms bonded in different orders
- Different properties
2
Q
Stereoisomerism
A
- Same molecular formula atoms bonded in same order
- Different 3D arrangement
3
Q
Conformational
A
- Rotation around σ bonds and 3D shape of sp3 centre
- All single bonds are free to rotate
- Although might be restricted by nearby bulky groups
4
Q
Configurational
A
- No conversion by rotation of single bond
- Only applies when the two ends of the double bond have the same groups attached
- Identical groups are on different sides - trans
- Identical groups are on the same side - cis
5
Q
Montelukast
A
Symptomatic relief of seasonal allergic rhinitis in patients with asthma and prophylaxis of asthma in children
6
Q
Geometric isomers
A
- Stereoisomers that arise due to restricted rotation
within a molecule - Different chemical and physical properties
7
Q
E/z isomerism configurational
A
- Look at groups with the highest priority are on diffrent sides E
- High priority on the same side Z
8
Q
Achiral molecule
A
- Compound and its mirror image are the same, can be superimposed
9
Q
Enantiomers
A
- Same physical/chemical properties
- Differ in activities with plan polarised light that gives rise to optical isomerism, and also in their pharmacological actions
10
Q
Chiral centres
A
2^n number of sterioisomers
11
Q
Chiral molecules
A
- Rotate plane-polarised light called optical activity
- Mixture that contains more of one enantiomer the other is optically active
12
Q
Racemic mixture
A
- Mixture of two diffrent enantiomers 50:50 ratio of two isomers
13
Q
Configuration of optical isomer dextrorotatory
A
Rotation clockwise direction
14
Q
Configuration of optical isomer levorotatory
A
Anticlockwise rotation
15
Q
R and S systems
A
- Count priority around chiral centre
- look at the direction
- Clockwise R and anticlockwise is S
