Lecture 14- Carbohydrate Structure

Question 1

Constitutional

Answer 1

• The order of atoms CHANGES (connectivity)

- Tautomers (following hydrogens- where does it move)

Question 2

Fisher projections

Answer 2

Linear versions of carbohydrates

Question 3

Tautomers

Answer 3

1. Aldose (C1=O)

2. Ketose (C2=O)

Question 4

Steroisomers

Answer 4

SAME connectivity but DIFFERENT spatial organizations

Question 5

Configurational isomers

Answer 5

Chiral carbons (2 types: diastereomers and enantiomers)

Question 6

Enantiomers

Answer 6

Mirror images at ALL chiral centers

Question 7

Diastereomers

Answer 7

Multiple chiral centers, however not all chiral centers are mirror images

Question 8

How do you determine L/D?

Answer 8

Last chiral carbon with OH determines L/D

If OH on left then L, if OH on right then D

Question 9

Haworth Projections

Answer 9

Ring/cyclical versions of carbohydrates

Question 10

Anomers

Answer 10

Differ at the anomeric C only!

Either alpha or beta

Question 11

Alpha carbon

Answer 11

DOWN

Question 12

Beta carbon

Answer 12

UP

Question 13

Epimers

Answer 13

Differ at any OTHER C than the anomeric C

Same alpha or beta BUT different @ carbons

Question 14

Left side of fisher projection

Answer 14

UP

Question 15

Right side of fisher projection

Answer 15

DOWN

Question 16

Conformational isomers

Answer 16

REVERSIBLE rotation changes

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