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Flashcards in 2Monosaccharides Deck (34):
0

Most sugars are _____handed sugar

Right-handed

1

Base all sugars on which molecule?

D-Glyceraldehyde

CHO
l
H- C - OH*
l
CH2O

2

Aldose sugars have ____

Aldehyde group

3

Remember the six types of aldose sugars:

(3)D – glyceraldehyde,
(4)D – erythrose,
(5)D – ribose,
(6)D – glucose, D – mannose, D – galactose

4

D-Erythrose structure (4)

H O
\ //
H-C-OH
l
H-C-OH*
l
CH2OH

5

D-Threose structure (4)

H O
\ //
C
l
OH-C-H
l
H- C- OH*
l
CH2OH

6

D-Ribose structure(5)

H O
\ //
C
l
H-C-OH*
l
H-C-OH*
l
H-C-OH*
l
CH2OH

7

D-Arabinose

Just know similar to ribose

H O
\ //
C
l
HO-C-H
l
H- C-OH
l
H- C-OH
l
CH2OH

8

D-Xylose structure (5)

Just remember similar to ribose

H O
\ //
C
l
H-C-OH
l
HO-C-H
l
H- C-OH
l
CH2OH

9

The reference compound for naming D and L isomers of sugars is:

Glyceraldehyde

10

D-Glucose structure

R-L-R-R


H O
\ //
C
l
H- C-OH
l
OH-C-H
l
H- C-OH
l
H- C-OH
l
CH2OH

11

D- Mannose structure
(Only c#2 changed from glucose)

LLRR

H O
\ //
C
l
HO-C-H
l
HO-C-H
l
H- C-OH
l
H- C-OH
l
CH2OH

12

D-Galactose (6Carbons)

C#4 is different

RLLR

H O
\ //
C
l
H-C-OH
l
HO-C-H
l
HO-C-H
l
H- C-OH
l
CH2OH

13

What is epimeric pair?

D- glucose and D-mannose

14

Two major classes- the Aldose and ketose sugars

Glyceraldehyde (an aldotriose)

H O
\ //
C
l
H- C-OH
l
H- C-OH
l
H





Dihydroxyacetone (a ketotriose)

H
l
H- C-OH
l
C=O
l
H- C-OH
l
H

15

Ketose Sugars-2 structures to know

Dihydroxyacetone (3 carbons)
CH2OH
l
C=O
l
CH2OH


D-fructose (6carbon)
CH2OH
l
C=O
l
HO-C-H
l
H- C-OH
l
H- C-OH
l
CH2OH

Similar to glucose except ketone at C#2

16

Which of the following is an epimeric pair?

(2 isomers differ in configuration at one stereo center)

D-glucose and D-mannose

17

Which of the following monosaccharides is not an Aldose?

Fructose

18

When the linear form of glucose cyclizes, the product is an:

Hemiacetal

19

Draw glyceraldehyde. How many stereoisomers can there be?

2

20

Draw glycerol. How many stereoisomers are there?

1

21

D-glucose is epimeric ex on carbon #2. What did it become?

D-mannose

22

Is D-2 deoxyglucose the same thing as D-2-deoxygalactose?

No

23

What biochemical feature is common in cellulose and is not found in glycogen?

Beta 1-4 bonds

Glycogen has alpha 1-4 bond

24

Which of the following monosaccharides is not an Aldose ?

Fructose

25

Hemiacetal is made up of:

Aldehyde + Alcohol

26

Hemiacetal can react with additional alcohols and form...

Acetal + water

This reaction makes it less spontaneous and more stable. Split out water and more difficult.

27

Ketone + alcohol=

Hemiketal

28

Hemiketal can react with additional alcohol to form

Ketal

29

2 glucose molecules react:

Carbon #4 alcohol + hemiacetal carbon #1

Disaccharide form with acetal linkage

Glc(alpha 1➡️4) Glc

Reducing sugar because of the right side of the right sugar it still has a free carbon number one which is a hemiacetal which can still open up to form an aldehyde and therefore still has the ability to become a reducing sugar.

30

Galactose+ glucose

Lactose

Reducing sugar

Gal(Beta1➡️4) Glc

Galactose is almost identical to glucose but carbon number four is flipped compared to glucose so the OH group will be on top and the H group will be on bottom

Reducing sugar because the hemiacetal on the right still has the anime roc carbon free, carbon#1 is free. Hemiactrals can open up freely to aldehydes.

31

Glucose + Fructose

Table sugar- sucrose

* not a reducing sugar* both a mimetic carbons tied up in bonding to each other

Glc(alpha1↔️2Beta) Fru

Has an acetal and ketal bond at same time. Glucose c#1 is alpha conformation with OH group coming down from it but connected to anime roc carbon of fructose, which is a ketose) so form a ketone derivative on #2 of fructose.

32

2 animeric carbons of glucose attached to each other

Trehalose

*Not a reducing sugar*

Glc(alpha1↔️1 alpha) Glc

33

Which two sugars is not a reducing sugar?

Sucrose and trehalose