Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Orgo2 > Carbohydrates > Flashcards

Carbohydrates Flashcards

1
Q

What is the biological significance of carbohydrates?

A

The most abundant and naturally occuring class of biomolecules

made primarily by plants (photosynthesis) and we consume them for energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What does cellulose and chitin serve a purpose of?

A

Have a structural role

(carbs can play a role in drugs too)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a glycoprotein?

A

a protein chain w short branched carb chains coming off of it

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is proteoglycans (mucopolysaccharides)?

A

proteins with long, linear carb chains off the amino acid
(found in connective tissues)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is peptidoglycans?

A

long carb chains linked in between by short oligopeptides

(bacterial cell walls)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Lipopolysaccharides?

A

fatty acids that are linked to carbohydrates

(outer envelope of gram negative bacteria)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Simple sugar formula?

A

Cn(H2O)n

(polyhydroxyaldehydes or polyhydroxyketones or compound that form these upon hydrolysis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What is a monosaccharide?

A

one sugar
defined a carb that cannot be hydrolyzed in the lab using H+/H2O to a simpler carb

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Monosaccharides can be broadly classified according to their number of ________?

A

carbon atoms

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

what does the suffix -ose mean?

A

a sugar

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

naming carbs?

A

prefix w number of carbons then suffix with -ose

ex. pentose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is an aldose?

A

A monosaccharide with an aldehyde

C=O
|
H

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is a ketose?

A

A monosaccharide with a ketone group
=O
assumed ot be on position 2 if not specified

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Combined classification method with number of carbons and carbonyl group present

A

ex. aldohexose

an aldose with 6 carbons

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

how are ketose combinations named?

A

Keto can be dropped and the suffix can be ulose

ex pentulose is the same as ketopentose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What is the smallest most simple monosaccharide?

A

C3 sugars
two trioses one is an aldose and one is a ketose

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

How are fischer projections of sugars drawn?

A

The aldehyde is on top

(most oxidized carbon is drawn on top)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Glyceraldehyde

A

D will rotate to the right
L will rotate left
this is just a coincidence they arent related

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Natural sugars are usually in _______ configuation.

A

D

(amino acids are usually L)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

D/L nomenclature for carbohydrates

A

D sugars have the OH on the penultimate carbon to the right

L sugars have the OH to the left

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What do +/- indicate in nomenclature?

A

+ rotates to the right
- rotates to the left

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

If two sugars have the same common name but are opposite in D and L they can be classified as?

A

enantiomers
all chiral centres have oppositie configurations

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

If two sugars with the same number of carbons dont have all opposite configuattion but some it is called a?

A

diasteriomer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How to identify number of stereoisomers?

A

2^(n)
n=number of steriocenteres

a 3C has 1 stereocentre
4C has 2
etc

25
Q

What is a furanose?

A

5-membered cyclic sugar

origin from a furan

26
Q

What is a pyranose?

A

6-membered cyclic sugar

orgininate from a pyran

26
Q

Formation of hemiacetals occur between the:

A

most oxidized carbon and the OH on the penultimate carbon

27
Q

In hemiacetals the rxn is exclusively _______?

A

intramolecular because these rxn are more favourable than intermolecular rxns

28
Q

When a hemiacetal cyclic sugar is formed it forms a new ______?

A

Stereocenter

29
Q

What is the anomeric carbon?

A

the new stereocenters that forms in the hemiacetal, the other stereocenters remain unchanged

30
Q

What is a B vs A anomer?

A

when OH and CH2OH is on the same side (Beta) cis

when on opp sides (alpha) trans

anomers are also diastereomers

this method of assigning a/b works only if the penultimate OH is involved in hemiacetal formation

31
Q

What is mutarotation?

A

Hemiacetals readily revert back to their carbonyl and alcohol components-anomers interconvert in aqueous solutions

thus when one anomer is dissolved an equilibrium of both mixtures form over time

32
Q

What is a glycosides?

A

Acetals of Sugars

when a hemiacetal reacts with another alcohol to form glycosides

called O-glycosides bc the oxygen is the nuc

33
Q

Glycosides (acetals) are stable in what conditions?

A

basic and neutral pH

34
Q

What is a glycosidic linkage?

A

A glycosidic bond or glycosidic linkage is a type of ether bond that joins a carbohydrate molecule to another group

attaches at the anomeric carbon

35
Q

What is an aldonic acid?

A

CHO -> COOH oxidation

36
Q

What oxidized only the CHO?

A

weak oxidizing agents

37
Q

Halides are strong _______ agents?

A

Oxidizing agents

38
Q

What are strong oxidizing agents?

A

Bromine
Metal ions
Benedicts or Fehling’s reagent

39
Q

What is an aldaric acid?

A

when both the aldehyde and primary OH are oxidized.

40
Q

What is nitric acid used for (HNO3)?

A

strong oxidizing agent
it oxidizes the aldehyde and primary OH

to weak for secondary OHs

41
Q

Meso compounds

A

achiral
optically inactive
has a plane of symmetry

42
Q

what is the purpose of oxidation to uronic acids?

A

only the bottom (primary OH) is oxidized and makes a uronic acid which helps the body excrete unwanted materials

done by enzymes

43
Q

reduction to alditols

A

makes the aldehyde a primary OH

makes sugar alcohols (bc they are poorly metabolized by the body)
(sugar free things)

ex sorbitol
xylitol
if a ketose are reduces a new stereo centre may be formed

44
Q

Aldehydes and ketones with an alpha hydrogen can form an ________.

A

enolate anion.

45
Q

the formation of an enolate destorys the stereochem at the ______.

A

ALPHA CARBON

46
Q

If any one of the D-glucose, D-manose, or D-fructose were placed in a basic solution what would happen?

A

the same equilibrium mixture of all three is formed

they are all structural isomers of each other

47
Q

What is an epimer?

A

are diastereomers that differ in the configuation of one stereocentre

ex d-glucose and d-mannose

48
Q

d-mannose and fructose are _______.

A

consitiutional isomers

49
Q

How does epimerization work?

A

so when you lose an H it makes the molec planar when it is planar when the H is added back it can attack from both sides making the two forms

50
Q

Why does ketoses sometimes give a false + for a reducing aldehyde?

A

bc there is succesive tautomerizations which creates a reducing aldehyde

51
Q

What is an aldol rxn?

A

when an enolate attacks an aldehyde or ketone

it forms a new carbon carbon bond

52
Q

what is the reverse of an aldol rxn?

A

glycolysis (retro-aldol rxn)

53
Q

what is an esterification?

A

When the OH groups convert into an ester using an acid derivative more reactive than ester like an anhydride

54
Q

What is an etherification?

A

when OH are convered to alkoxides and then they are good nucs that convert to form ethers

using DMSO

55
Q

Killiani-fischer synthesis of monosaccharides

A

-carbon-chain lengthening procedure that extends monosachrides by one carbon

uses CN-

two methods
traditional
modern

56
Q

traditional method for synthesis of monosaccs?

A

use CN-
add hydroxide
then make a salt

then put in seperate flasks where they are converted back to a lactone with acid and reduced to an aldehyde

57
Q

modern method

A

uses a catalyst to reduce the nitrile to an imine then hydroylis of the imine results in the aldehye
better bc fewer steps and toxic agents

diassteromertic products can be serperated through HPLC

Orgo2 (7 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions