Chemistry Reference
In-Depth Information
AcO
OAc
OAc
O
AcO
AcO
OAc
O
OAc
AcO
O
AcO
(a)
N
3
OAc
O
O
O
AcO
AcO
AcO
N
3
OAc
AcO
OAc
CuSO
4
AcO
O
O
AcO
O
O
OAc
+
sodium ascorbate
O
O
O
AcO
OAc
AcO
O
AcO
AcO
OAc
AcO
H
2
O,MW, 70°C
AcO
O
N
N
N
N
O
AcO
AcO
N
N
AcO
O
O
AcO
OAc
(b)
OAc
OH
HO
21
OH
HO
OH
OH
O
O
O
O
O
HO
N
O
O
N
HO
HO
O
HO
HO
HO
HO
O
N
HO
N
N
HO
HO
OH
O
HO
OH
N
OH
22
OH
O
O
O
O
HO
HO
HO
O
OH
HO
HO
O
O
HO
N
N
23
OH
O
HO
N
OH
HO
OH
HO
O
OH
OH
HO
O
OH
O
HO
HO
O
OH
O
O
HO
HO
HO
O
HO
OH
HO
OH
O
OH
O
N
N
HO
O
O
O
HO
O
OH
HO
O
HO
N
X
O
HO
O
N
N
HO
n
HO
HO
O
N
OH
N
HO
OH
O
N
OH
O
HO
N
O
O
O
X
HO
N
N
O
HO
OH
n
OH
HO
O
O
O
HO
OH
N
HO
N
OH
N
OH
O
O
O
O
N
HO
24
O
OH
HO
HO
O
X
N
N
HO
OH
n
OH
N
OH
O
OH
HO
OH
O
O
O
HO
O
HO
OH
HO
X
O
HO
N
n
N
OH
O
N
25
X=OCH
2
, n=0
26
X=O, n=2
OH
OH
SCHEME 13.4
(a) General procedure of Cu(I)-catalyzed reactions between azido-sugar
cores and alkyne lactosides, exemplified for
21
. (b) Structures of mono-
22
and multivalent
lactoside triazoles
23
-
26
.
selective cell adhesion molecules interact with leukocytes, leading, at first, to their
characteristic tethering and rolling on the vascular endothelium. Subsequently, adhe-
sion and migration of leukocytes through the endothelial monolayer, whereby they
interact transiently with selectins, lead to their extravasation, originally intended as a
defensive strategy [23]. However, when occurring in excess, extravasation of leuko-
cytes to inflammation sites can cause severe acute or chronic reactions, such as stroke,
psoriasis, and rheumatoid arthritis. Thus, the inhibition of selectins can be consid-
ered as an important approach for the treatment of inflammatory diseases. To date,
only three selectins have been identified: L-selectin, expressed on all leukocytes; E-
selectin, expressed by cytokine-activated endothelial cells; and P-selectin, expressed
Search WWH ::
Custom Search