Biology Reference
In-Depth Information
OH
O
HO
HO
OH
NH
2
OH
O
O
OH
O
+
O
O
OH
O
HO
OH
OH
HO
HO
O
OH
n
O
HO
OH
5
OH
NaBH
3
CN
OH
O
OH
OH
O
HO
HO
OH
O
OH
HO
OH
O
5
OH
HO
OH
NH
2
HN
O
O
O
O
O
O
OH
HO
HO
OH
OH
HO
n
Glc-1-P
Phosphorylase
OH
O
OH
OH
O
HO
HO
OH
O
OH
OH
HO
O
m
OH
HO
OH
NH
2
HN
O
O
O
O
O
O
OH
HO
HO
OH
OH
HO
n
Figure 6.4
Chemoenzymatic synthesis of amylose-grafted cellulose by
means of phosphorylase-catalyzed enzymatic polymerization.
amination, giving rise to the maltooligosaccharide-grafted cellulose.
Therefore, the synthesis of amine-functionalized cellulose was first
performed, which was successfully obtained by three reaction steps,
i.e., the partial tosylation of the OH groups at C-6 positions, the
displacement of the tosylates by the azido groups, and the reduction
to the amino groups (Fig. 6.5).
The reductive amination of the amine-functionalized cellu-
lose with maltoheptaose was carried out by a reaction procedure
same as that of chitosan with maltoheptaose as aforementioned.
Subsequently, the synthesis of the amylose-grafted cellulose was
performed by the phosphorylase-catalyzed enzymatic polymeriza-
tion of Glc-1-P from the maltooligosaccharide graft chains on cellu-
lose (Fig. 6.4).
