L9 - Carbohydrates I

Question 1

General Formula

Answer 1

(CH2O)n

Question 2

Functions of Carbohydrates

Answer 2

Photosynthesis
Fuels
Nucleic Acids
Structure
Recognition

Question 3

Features of Monosaccharides

Answer 3

Simplest Carbohydrates
One aldehyde/ketone
Multiple hydroxyls
Usually 3-7C
-ose suffix

Question 4

Aldoses

Answer 4

Aldehyde group
Chiral carbon on 2 or greater
Aldehyde on Carbon 1
Isomers = 2^n - n= no. of chiral carbons
+ alcohol = Hemiacetal

Question 5

Ketoses

Answer 5

Ketone group
Chiral carbon on 3 or greater
Ketone on carbon 2
+ alcohol = Hemiaketal

Question 6

Cylisation

Answer 6

Hexose and pentose from rings in soln
Anomeric carbon = c-1 aldoses, c-2 for ketoses

Question 7

Anomers

Answer 7

Alpha and Beta isomers of cyclic monosaccharides

Question 8

Furanose

Answer 8

5 membered rings

Question 9

Pyranose

Answer 9

6 membered ring

Question 10

Mutarotation proof

Answer 10

Beta rotates light 18.7 degrees
Alpha rotates light 112 degrees
OPTICAL ROTATION
Pure sample dissolved in water changes to 52.7 degrees
1/3 Alpha, 2/3 Beta

Question 11

Pyranose ring shape

Answer 11

Chair or Boat

Question 12

Furanose ring shape

Answer 12

Envelope