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(a)
(b)
Saturated phospholipid
Carotenoid
FIGURE 3.1
(a) “Carotenoid aggregate” from saturated surfactants with enclosed carotenoids. (b) Real caro-
tenoid aggregate built of carotenoid surfactants.
O
O
Cl
Cl
Br
P
O
O
O
O
HO
HO
O
OH
OPO
3.14
3.12
Br
O
N (CH
3
)
3
O
O
HO
O
OPO
N
3.15
+
O
O
O
O
-
+
OH
HO
O
PO
+
H
OH
N
3.11
(
R
)-
3.16
N
NN
N
O
N
N
O
O
O
O
PO
+
H
OH
N
O
-
(
R
)-
3.15
SCHEME 3.6
lyso compound,
3.15
, is tricky and, not astonishingly, previous attempts in synthesizing carotenoid
phosphatidylcholines had failed (Benade 2001). Later, sodium phosphate groups were successfully
introduced to lutein,
3.4
, and lycophylldiol, resulting in the phosphoesters,
3.17
and
3.18
, respec-
tively, Scheme 3.7 (Foss et al. 2006a). Groups at Hawaii Biotech, Inc., Albany Molecular Research,
Inc., and Cardax Pharmaceuticals, Inc. systematically exploited Method 1, Scheme 3.3, for the
synthesis of hydrophilic carotenoids. Hydroxy carotenoids such as zeaxanthin,
3.3
, lutein,
3.4
, and
especially astaxanthin,
3.6
, were systematically modii ed with a multitude of different hydrophilic
groups, which were connected to the two hydroxyl groups in these carotenoids. This approach was
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