Biomedical Engineering Reference
In-Depth Information
AlEt
2
O
O
Et
2
AlCl, CH
2
Cl
2
-78° to rt, 12 h
CO
2
Me
CO
2
Me
Me
Me
Cl
TMS
TMS
12
13
AlEt
2
O
OH
H
CO
2
Me
H
H
CO
2
Me
50%
Me
H
H H
Me
15
14
steps
OH
NH
O
O
H
H
O
H H
Me
Hirsutellone B
16
SCHEME 9.3
Synthesis of hirsutellone B
16
by Nicolaou and coworkers.
product. Hence, treating this compound with
N
-(phenylseleno)phthalimide at 0
C
provided the intermediate
23
, which in turn reactedwith the adjacent epoxide to give
24
the bicyclic epoxonium ion
(Scheme 9.5) [13]. From this intermediate, a second
cyclization through the 6-
endo
mode afforded the phenyl selenide
25
as a single
H
H
HO
O
O
H
OH
H
O
TMS
H
H
O
H
18
Abudinol B
17
75%
TMSOTf
H
H
O
3
, CH
2
Cl
2
, -78°C
then Me
2
S, -78°C to 20°C
88%
TMSO
RO
O
H
H
O
H
O
H
H
H
20
: R = TMS
19
Bu
4
NF, THF
99%
21
: R = H
ent
-
17
SCHEME 9.4
Synthesis of
ent
-nakorone
(21)
and
ent
-abudinol (
ent
-
17
).
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