Biomedical Engineering Reference
In-Depth Information
NMe
3
N
3
HO
MeCN/THF (1:1)
70°C
P(
n
-Bu)
2
HO
HO
(1)
N
Br
(100% conv)
N
3
(1) rt; (2) 55°C
(2)
MeO
128
129
OMe
132
NMe
3
RuO
4
OH
O
THF, rt
H
MeO
MeO
(100% conv)
H-Cube
10% Pd/C, THF
OMe
OMe
130
131
HO
O
HO
80°C
PhI(OCOCF
3
)
2
CH
2
Cl
2
MeO
N
N
H
O
CF
3
MeO
N
MeO
MeO
CF
3
O
O
OMe
OMe
O
135
134
133
F
3
C
O
CF
3
CH
2
Cl
2
O
NMe
3
OH
35°C
MeO
MeOH/H
2
O (4:1)
70
H
μ
L/min
N
MeO
(±)-Oxomaritidine 7
40% overall
(>90% purity by
1
H NMR)
SCHEME 11.42
A new paradigm for molecular assembly: a flow process for the multistep
synthesis of the alkaloid natural product (
)-oxomaritidine
7
.
membered tricyclic spirodieneone intermediate
. The product was then released
directly into a column that contained an immobilized base to effect hydrolysis and the
free amine spontaneously generates the target compound (
135
)-oxomaritidine (
7
)in
40% overall yield and high purity.
H
2
N
138
OH
O
then
HOBt
SO
3
H
MeO
N
H
HO
139
OH
O
H
2
O
2
-urea complex
Buffer pH 4.5
MeO
OH
HO
137
HO
Horseradish Peroxidase
N
P
+
N
N
Br
PF
6
-
NH
OH
O
O
136
H
HO
DIPEA
O
Grossamide
140
MeO
OMe
SCHEME 11.43
Flow synthesis of grossamide
140
.
Search WWH ::
Custom Search