Polyfunctional Natural Products: Carbohydrates

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Polyfunctional Natural ProductsCarbohydrates

• 24.1 Nomenclatuur and Structure (page 1235)

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Polyfunctional Natural ProductsCarbohydrates

• 24.1 Nomenclatuur and Structure (page 1235)

Problem 24.1 Generalize from the definition of a
triose to generate the structures of an
aldotetrose and an aldopentose.
Glyceraldehyde is an aldotriose because it has a
three-carbon backbone and an aldehyde group. Fig.
24.2
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Polyfunctional Natural ProductsCarbohydrates

• 24.1 Nomenclatuur and Structure (page 1236)

Aldo sugars are written with the aldehyde group
at the top and the primary alcohol at the bottom.
In this scheme, called a Fischer projection,
horizontal bonds are taken as coming toward the
viewer and vertical bonds as retreating. If the
OH adjacent to the primary alcohol at the bottom
is on the right, the sugar is a member of the D
series. If it is on the left, it is in the L
series. Fig. 24.3
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Polyfunctional Natural ProductsCarbohydrates

• 24.1 Nomenclatuur and Structure (page 1237)

There is no relation between D and L and the sign
of optical rotation, () and (-). Fig. 24.4
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Polyfunctional Natural ProductsCarbohydrates

• 24.1 Nomenclatuur and Structure (page 1237)

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Polyfunctional Natural ProductsCarbohydrates

• 24.1 Nomenclatuur and Structure (page 1237)

Problem 24.3 Write Fischer projections for the
molecules in Figure 24.6
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Polyfunctional Natural ProductsCarbohydrates

• 24.1 Nomenclatuur and Structure (page 1237)

22 stereoisomers both D and L isomers shown
23 stereoisomers only D-diastereoisomers shown!
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Polyfunctional Natural ProductsCarbohydrates

• 24.1 Nomenclatuur and Structure (page 1238)

24 stereoisomers only D-diastereoisomers shown!
The eight D-aldohexoses Fig. 24.10
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Polyfunctional Natural ProductsCarbohydrates

• 24.1 Nomenclatuur and Structure (page 1238)

D-Fructose, a common ketohexose. Fig. 24.10
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Polyfunctional Natural ProductsCarbohydrates

• 24.1 Nomenclatuur and Structure (page 1238)

Problems 24.4 24.5 Problem 24.6 Treatment of
D-glucose with sodium borohydride (NaBH4) gives
D-glucitol (sorbitol), C6H14O6. Show the
structure of D-glucitol and write a brief
mechanism for this simple reaction
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Polyfunctional Natural ProductsCarbohydrates

• 24.1 Nomenclatuur and Structure (page 1239)

Why?
Although reduction with sodium borohydride,
followed by hydrolysis, proceeds normally to give
an alcohol, neither NMR or IR reveals large
amounts of an aldehyde in the starting
material. Fig. 24.12
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Polyfunctional Natural ProductsCarbohydrates

• 24.1 Nomenclatuur and Structure (page 1239)

Intramolecular hemiacetal formation is analogous
to hydration and intermolecular hemiacetal
formation. Five- and six-membered ring
hemiacetals are easily made, and are often more
stable than their open forms. Fig. 24.13
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Polyfunctional Natural ProductsCarbohydrates

• 24.1 Nomenclatuur and Structure (page 1240)

Example
Intramolecular hemiacetal formation is analogous
to hydration and intermolecular hemiacetal
formation. Five- and six-membered ring
hemiacetals are easily made, and are often more
stable than their open forms. Fig. 24.13
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Polyfunctional Natural ProductsCarbohydrates

• 24.1 Nomenclatuur and Structure (page 1241)

In an aldohexose, intramolecular hemiacetal
formation results in a furanose (five-membered
ring) or pyranose (six-membered ring) Fig. 24.14
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Polyfunctional Natural ProductsCarbohydrates

• 24.1 Nomenclatuur and Structure (page 1241)

Fischer projections for D-glucofuranose and
D-glucopyranose Fig. 24.5
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Polyfunctional Natural ProductsCarbohydrates

• 24.1 Nomenclatuur and Structure (page 1242)

If two compounds are in equilibrium, irreversible
reaction of the minor partner can result in
complete conversion into a product. As long as
the equilibrium exists, the small amount of the
reactive molecule will be replenished as it is
used up. Fig. 24.16
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Polyfunctional Natural ProductsCarbohydrates

• 24.1 Nomenclatuur and Structure (page 1242)

Intramolecular hemiacetal formation results in
two C(1) stereoisomers called anomers. Fig.
24.17
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Polyfunctional Natural ProductsCarbohydrates

• 24.1 Nomenclatuur and Structure (page 1245)

The first step in creating a three-dimensional
drawing is rotation around the indicated
carbon-carbon bond. This motions generates a new
Fischer projection. Fig. 24.19
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Polyfunctional Natural ProductsCarbohydrates

• 24.1 Nomenclatuur and Structure (page 1245)

Problem 24.9 Draw the flat, Haworth form of the
?-anomer.
Next, tip the molecule over in clockwise fashion
to produce a flat Haworth form Fig. 24.20
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Polyfunctional Natural ProductsCarbohydrates

• 24.1 Nomenclatuur and Structure (page 1245)

Problem 24.10 Follow this same procedure for the
?-anomer.
Now let the flat, Haworth form relax to a chair.
Dont forget that there are always two possible
chair forms. Fig. 24.21
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Polyfunctional Natural ProductsCarbohydrates

• 24.1 Nomenclatuur and Structure (page 1246)

Problem 24.11 Transform the Fischer projection
into a three-dimensional picture of
D-mannopyranose
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1246)
• 24.2a Mutarotation of Sugars

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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1246)
• 24.2a Mutarotation of Sugars

The ?- and ?-anomers can equilibrate through the
small amount of the open form present at
equilibrium Fig. 24.22
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1247)
• 24.2a Mutarotation of Sugars

Problem 24.12 Write a mechanism for the
acid-catalyzed mutarotation of D-glucopyranose
(in 3-dimensional structures!)
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1246)
• 24.2b Isomerization of Sugars in Base

Explain!
In base, D-glucose equilibrates with D-mannose
and D-fructose, a keto sugar. Fig. 24.23
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1248)
• 24.2b Isomerization of Sugars in Base

Lobry de Bruijn-Alberda van Ekenstein reaction!
A mechanism of the equilibration of D-Glucose and
D-mannose involves formation of an enolate
followed by reprotonation Fig. 24.24
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1248)
• 24.2b Isomerization of Sugars in Base

Protonation on oxygen generates a double enol,
which can lead to D-fructose (or the
D-aldohexoses, D-glucose, and D-mannose). Fig.
24.25
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1249)
• 24.2c Reduction

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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1249)
• 24.2c Reduction

Problem 24.15 Reduction of D-altrose with sodium
borohydride in water gives an optically active
molecule, D-altritol. However, the same procedure
aplied to D-allose gives an optically inactive,
meso hexa-alcohol. Explain.
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1250)
• 24.2d Oxidation

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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1250)
• 24.2d Oxidation

Problem 24.16 Write a mechanism for this
oxidation. Hint for the first step What reaction
is likely between an aldehyde and water?
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1250)
• 24.2d Oxidation

Problem 24.17 Examination of the NMR and IR
spectra of typical aldonic acids often shows
little evidence for the carboxylic acid group.
Explain this odd behavior.
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1251)
• 24.2d Oxidation

Oxidation with nitric acid generates an aldaric
acid in which the end groups are both carboxylic
acids. Figure 24.28
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1251)
• 24.2e Ether and Ester formation

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Polyfunctional Natural ProductsCarbohydrates

• 17.10 Synthesis of Ethers from Alkoxides (pag
  845)

Formation of ethers via Sn2 process!
Williamson ether synthesis!!
Alkoxides can displace halides in an SN2 reaction
to make ethers. This reaction is the Williamson
ether synthesis. Figure 17.56
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Polyfunctional Natural ProductsCarbohydrates

• 17.10 Synthesis of Ethers from Alkoxides

Formation of ethers via Sn2 process!
Williamson ether synthesis!!
Alkoxides can displace halides in an SN2 reaction
to make ethers. This reaction is the Williamson
ether synthesis. Figure 17.56
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1251)
• 24.2e Ether and Ester formation

Formation of ethers via Sn2 process!
Williamson ether synthesis!!
A similar process can be carried out in base with
a Williamson ether synthesis. Notice in this
example that neither the existing ether at C(1)
nor the pyranose ring connection is disturbed in
the benzylation. Figure 24.30
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1251)
• 24.2e Ether and Ester formation

?
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1251)
• 24.2e Ether and Ester formation

All the free hydroxyl groups can be esterified
with acetic anhydride. Figure 24.30
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1253)
• 24.2e Ether and Ester formation

?
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1253)
• 24.2e Ether and Ester formation

Treatment with dilute HCl and alcohol converts
only the OH at the anomeric position C(1) into
an acetal called a glycoside. Figure
24.32
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1253)
• 24.2e Ether and Ester formation

Glycoside!
Why only methoxylation at the C-1 position?
Treatment with dilute HCl and alcohol converts
only the OH at the anomeric position C(1) into
an acetal called a glycoside. Figure
24.32
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1253)
• 24.2e Ether and Ester formation

Although all OH groups can be reversibly
protonated, loss of only the anomeric OH leads to
a resonance-stabilized cation. Addition of
alcohol at this position gives the glycoside.
Figure 24.33
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1253)
• 24.2e Ether and Ester formation

Although all OH groups can be reversibly
protonated, loss of only the anomeric OH leads to
a resonance-stabilized cation. Addition of
alcohol at this position gives the glycoside.
Figure 24.33
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1254)
• 24.2e Ether and Ester formation

Methyl ?- and methyl ?-D-glucopyranosides. Figure
24.34
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1254)
• 24.2e Ether and Ester formation

?
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1254)
• 24.2e Ether and Ester formation

Hydrolysis of the fully methylated compounds
leads to a hemiacetal in which only the methoxyl
group at the anomeric position C(1) has been
converted into an OH. Figure 24.35
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1254)
• 24.2e Ether and Ester formation

Problem 24.18 Explain carefully why it is only
the acetal methoxyl group that is converted into
a hydroxyl group.
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1255)
• 24.2f Osazone Formation

What product would you expect from the above
reaction?
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1255)
• 24.2f Osazone Formation

What product would you expect from the above
reaction?
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1255)
• 24.2f Osazone Formation

The small amount of free aldehyde present at
equilibrium accounts for phenylhydrazone
formation at C(1). Figure 24.36
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1256)
• 24.2f Osazone Formation

Problem 24.14 Write a mechanism for the above
reaction.
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1256)
• 24.2f Osazone Formation

The actual reaction is far more complicated!
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1256)
• 24.2f Osazone Formation

Osazone formation involves conversion of C(2) as
well as C(1) into phenylhydrazones. Figure
24.37
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1256)
• 24.2f Osazone Formation

How come?
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1256)
• 24.2f Osazone Formation

The C(1) phenylhydrazone is an imine and
therefore in equilibrium with an enamine. This
enamine is also an enol. Figure 24.38
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Polyfunctional Natural ProductsCarbohydrates
Reaction of the ketone with phenylhydrazine leads
to a new phenylhydrazone that can eliminate
aniline to give a new imine. Reaction with a
third equivalent of phenylhydrazine leads to the
osazone. Figure 24.39
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1257)
• 24.2f Osazone Formation

Attention!!!!
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1257)
• 24.2g Methods of Lengthening and Shortening
  Chains in Carbohydrates

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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1257)
• 24.2g Methods of Lengthening and Shortening
  Chains in Carbohydrates

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Polyfunctional Natural ProductsCarbohydrates
Kiliani-Fischer Synthesis

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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1259)
• 24.2f Methods of Lengthening and Shortening
  Chains in Carbohydrates

Problem 24.20 Apply the Kiliani-Fischer synthesis
to D-glyceraldehyde. What new sugars are formed?
It is not necessary to write mechanisms for the
reactions.

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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1259)
• 24.2f Methods of Lengthening and Shortening
  Chains in Carbohydrates

Problem 24.21 The following two sugars are
produced by Kiliani-Fischer synthesis from an
unknown sugar (Fig. 24.42). What is the
structure of that unknown sugar?

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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1259)
• 24.2f Methods of Lengthening and Shortening
  Chains in Carbohydrates

The Ruff degradation

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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1259)
• 24.2f Methods of Lengthening and Shortening
  Chains in Carbohydrates

Mechanism complicated!

The Ruff degradation shortens the starting sugar
by one carbon. It is the original aldehyde carbon
that is lost! Figure 24.43
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Polyfunctional Natural ProductsCarbohydrates

• 24.2 Reactions of Sugars (page 1260)
• 24.2f Methods of Lengthening and Shortening
  Chains in Carbohydrates

The Wohl degradation

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Polyfunctional Natural ProductsCarbohydrates

• 24.4 The Fischer Determination of the
  Structures of D-Glucose (and the 15 other
  Aldohexoses (page 1262)

Accomplished by Emil Fischer in 1891
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Polyfunctional Natural ProductsCarbohydrates

• 24.4 The Fischer Determination of the
  Structures of D-Glucose (and the 15 other
  Aldohexoses (page 1263)

Second step Determining the configuration of
C(2) in arabinose by oxidation
Oxidation of D-arabinose leads to an optically
active diacid, which shows that the OH at C(2) in
D-arabinose is on the left. Figure 24.49
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Polyfunctional Natural ProductsCarbohydrates

• 24.4 The Fischer Determination of the
  Structures of D-Glucose (and the 15 other
  Aldohexoses (page 1263)

Current knowledge about the structures of
D-arabinose, D-glucose and D-mannose
What we now know about the structures of
D-arabinose, D-glucose, and D-mannose. Only the
configuration at C(3) of D-arabinose, which
becomes C(4) in D-glucose and D-mannose, is left
to be determined. Figure 24.50
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Polyfunctional Natural ProductsCarbohydrates
If true than both diacids should be optically
active upon oxidation with nitric acid!
Third step Determining the configuration of
C(4) in glucose en mannose by oxidation
Figure 24.51
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Polyfunctional Natural ProductsCarbohydrates
If true than both diacids should be optically
active upon oxidation with nitric acid!
Third step Determining the configuration of
C(4) in glucose en mannose by oxidation
Figure 24.51
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Polyfunctional Natural ProductsCarbohydrates
Third step Determining the configuration of
C(4) in glucose en mannose by oxidation
If true than only one acid should be optically
active!
Assumption OH on the left!
However, if the unknown OH is on the left, one
possible diacid is meso, not optically
active. Figure 24.52
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Polyfunctional Natural ProductsCarbohydrates
Third step Determining the configuration of
C(4) in glucose en mannose by oxidation
If true than only one acid should be optically
active!
However, if the unknown OH is on the left, one
possible diacid is meso, not optically
active. Figure 24.52
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Polyfunctional Natural ProductsCarbohydrates
Experimental Result Both sugars gave an
optically active diacid!
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Polyfunctional Natural ProductsCarbohydrates

• 24.4 The Fischer Determination of the
  Structures of D-Glucose (and the 15 other
  Aldohexoses (page 1265)

Now we know the structure of D-arabinose,
L-arabinose, and the two structures (A and B)
shared by D-glucose and D-mannose. We do not know
which structure belongs to D-glucose and which to
D-mannose Figure 24.53
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Polyfunctional Natural ProductsCarbohydrates

• 24.4 The Fischer Determination of the
  Structures of D-Glucose (and the 15 other
  Aldohexoses (page 1266)

Two different sugars may give the same aldaric
acid when oxidized!
Oxidation with nitric acid renders the ends of a
sugar equivalent. Both the aldehyde end and the
primary alchohol end are converted into the same
group, a carboxylic acid. Figure 24.54
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Polyfunctional Natural ProductsCarbohydrates

• 24.4 The Fischer Determination of the
  Structures of D-Glucose (and the 15 other
  Aldohexoses (page 1266)

Two different sugars may give the same aldaric
acid when oxidized!
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Polyfunctional Natural ProductsCarbohydrates

• 24.4 The Fischer Determination of the
  Structures of D-Glucose (and the 15 other
  Aldohexoses (page 1266)

If D-glucose has the structure A, oxidation of
another sugar, L-gulose, can give the same
aldaric acid. Note in this case that the L-gulose
is drawn with the CH2OH at the top and the CHO at
the bottom. Figure 24.55
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Polyfunctional Natural ProductsCarbohydrates

• 24.4 The Fischer Determination of the
  Structures of D-Glucose (and the 15 other
  Aldohexoses (page 1266)

If glucose would have structure B only glucose
would yield this aldaric acid!
However, there is no sugar other than B that can
give this aldaric acid. As this fact does not
match the experimental results, D-glucose must
have structure A. Figure 24.56
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Polyfunctional Natural ProductsCarbohydrates

• 24.4 The Fischer Determination of the
  Structures of D-Glucose (and the 15 other
  Aldohexoses (page 1266)

However, this is not true! Conclusion Glucose
has structure A!
However, there is no sugar other than B that can
give this aldaric acid. As this fact does not
match the experimental results, D-glucose must
have structure A. Figure 24.56
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Polyfunctional Natural ProductsCarbohydrates

• 24.4 The Fischer Determination of the
  Structures of D-Glucose (and the 15 other
  Aldohexoses (page 1266)

This outcome also reveals the structure of
L-Gulose!
However, there is no sugar other than B that can
give this aldaric acid. As this fact does not
match the experimental results, D-glucose must
have structure A. Figure 24.56
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Polyfunctional Natural ProductsCarbohydrates

• 24.4 The Fischer Determination of the
  Structures of D-Glucose (and the 15 other
  Aldohexoses (page 1267)

Structures unraveled sofar!
Now we know the structures of these aldohexoses
and aldopentoses. Figure 24.57
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Polyfunctional Natural ProductsCarbohydrates

• 24.4 The Fischer Determination of the
  Structures of D-Glucose (and the 15 other
  Aldohexoses (page 1268)

D-Arabinose and D-ribose give the same osazone,
and therefore can differ only at C(2). The
structure of D-ribose is therefore known.
L-Ribose is simply the mirror image of the
D-isomer. Figure 24.58
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Polyfunctional Natural ProductsCarbohydrates

• 24.4 The Fischer Determination of the
  Structures of D-Glucose (and the 15 other
  Aldohexoses (page 1268)

In a similar way the structures of all the other
aldopentoses and aldohexoses were
established. See Figures 24.59, 24.60, 24.61 and
24.62
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Polyfunctional Natural ProductsCarbohydrates

• 24.5 Something more Di- and Polysaccharides
  (page 1270)

Examples Disaccharides sucrose, lactose,
maltose, Polysaccharide cellulose
How can this structure be unraveled?
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Polyfunctional Natural ProductsCarbohydrates

• 24.5 Something more Di- and Polysaccharides
  (page 1270)

Hydrolysis shows the individual monosaccharides!
In acid, ()-lactose is hydrolyzed to D-glucose
and D-galactose. Figure 24.63
87
Polyfunctional Natural ProductsCarbohydrates
Hydrolysis in dilute acid means that there must
be a glycosidic linkage in ()-lactose Figure
24.64
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Polyfunctional Natural ProductsCarbohydrates

• 24.5 Something more Di- and Polysaccharides
  (page 1271)

The remaining questions about the structure of
()-lactose. Figure 24.65
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Polyfunctional Natural ProductsCarbohydrates
The acid group in lactobionic acid marks the
position of the aldehyde in ()-lactose. As
hydrolysis of lactobionic acid gives a gluconic
acid (not a galactonic acid), it is glucose that
has the free aldehyde in ()-lactose. Figure 24.66
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Polyfunctional Natural ProductsCarbohydrates
The acid group in lactobionic acid marks the
position of the aldehyde in ()-lactose. As
hydrolysis of lactobionic acid gives a gluconic
acid (not a galactonic acid), it is glucose that
has the free aldehyde in ()-lactose. Figure 24.66
We still dont know which OH is making the
connection!!!
91
Polyfunctional Natural ProductsCarbohydrates
The position of the OH used to attach glucose to
C(1) of galactose can be determined through a
series of methylation and hydrolysis
experiments. Figure 24.67
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Polyfunctional Natural ProductsCarbohydrates
The position of the OH used to attach glucose to
C(1) of galactose can be determined through a
series of methylation and hydrolysis
experiments. Figure 24.67
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Polyfunctional Natural ProductsCarbohydrates

• 24.5 Something more Di- and Polysaccharides
  (page 1274)

Problem 24.23 Make a good three-dimensional
drawing of ()-lactose
A Fischer projection for ()-lactose. Figure
24.67
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Polyfunctional Natural ProductsCarbohydrates

• 24.5 Something more Di- and Polysaccharides
  (page 1271)

Sucrose
No aldehyde oxidation with Br2/H2O possible!!!
-gt A nonreducing sugar
Suggest a basic structural feature for such a
sugar
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Polyfunctional Natural ProductsCarbohydrates

• 24.5 Something more Di- and Polysaccharides
  (page 1271)

Sucrose No aldehyde oxidation with Br2/H2O
possible!!!
-gt A nonreducing sugar
In nonreducing sugars, there is no free aldehyde
group. Attachment must be between both C(1)
atoms. Sucrose is an example. Figure 24.69
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Polyfunctional Natural ProductsCarbohydrates

• 24.5 Something more Di- and Polysaccharides
  (page 1276)

Polysaccharides
Cellulose and amylose Figure 24.70
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Polyfunctional Natural ProductsCarbohydrates

• 24.5 Something more Di- and Polysaccharides
• Problems 24.24 24.25
• 24.8 Additional Problems (page 1279)
• Problems 24.27 24.28 24.29 24.30 24.31
  24.32 24.33 24.34 24.37 24.38 24.39 24.40
  24.42 24.43 24.44 24.46 24.48