Chemistry Reference
In-Depth Information
BnO
OBn
BnO
BnO
O
O
OBn
N
43
or
44
N
N
O
BnO
1. MsCl
2. ethylene
diamine
O
HN
HN
O
BnO
O
N
N
N
OBn
BnO
O
O
OBn
BnO
BnO
BnO
BnO
BnO
O
45
O
BnO
OBn
N
N
N
yield without template
- 5%.
yield with template
- 25%.
O
BnO
O
HN
N
HN
template =
O
BnO
O
N
N
N
OBn
O
O
46
BnO
BnO
BnO
BnO
yield without template
- 0%.
yield with template
- 20%.
FIGURE 9.17
Cyclization of the linear symmetrical sucroses.
receptors. The functional groups (azide, acetylene) engaged in the preparation of
macrocycles can be placed at the desired position of sucrose molecule; such deriva-
tives are easily available from the parent disaccharide. The availability of differently
activated sucrose derivatives may open a route to much complex, sucrose-derived
products by their “click” coupling with other interesting molecules such as other
(biologically important) sugars, amino acids, or peptides.
Although we have not yet prepared such “click-derived” macrocycles in a free
form, we believe they are available. We have already reported that fully benzylated
sucrose macrocycles (e.g.,
27
in Fig. 9.10) can be easily deprotected [42]. This result
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