protective colloid, binder, stabilizer and suspending agent, particularly in
applications where a nonionic material is desired. Natrosol is also used in
cosmetic preparations as a thickening agent for shampoos, conditioners,
liquid soaps and shaving creams.
6.3.11 Miscellaneous carbohydrates
Sugar phosphates
These sugars are formed by phosphorylation with ATP, e.g. glucose
6-phosphate. They are extremely important in carbohydrate metabolism.
We have already seen that nucleotides contain sugar phosphates.
OH
O
O 3 PO
O
H O
H
OH
Glucose 6-phosphate
2Nitrogen-containing sugars
Glycosylamines In these sugars, the anomeric –OH group (of common
sugars) is replaced by an amino (–NH 2 ) group: for example, adenosine.
O
O
H
OH OH
N
N
N
N
NH 2
Adenosine, a nucleoside
O
O
H
O
H O
H
NH 2
OH
Glucosamine, an amino sugar
Amino sugars In amino sugars, a non-anomeric –OH group (of common
sugars) is replaced by an amino (–NH 2 ) group: for example, glucosamine,
which is found in exoskeletons of insects and crustacea, and also isolated
from heparin (anticoagulant in mast cells in arterial cell walls). Other amino
sugars are found in antibiotics such as streptomycin and gentamicin.
Carbohydrate antibiotics Antibiotics that contain one or more amino
sugars within the molecule are called carbohydrate antibiotics. For example, gentamicin is composed of three different units: purpurosamine,
2-deoxystreptamine and garosamine. Other examples include streptomycin
and neomycin.
6.3 CARBOHYDRATES
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