Biomedical Engineering Reference
In-Depth Information
OH
OH
1. C
9
H
19
CHO
80°C
Bn
Bn
HO
[3,3]
C
9
H
19
C
9
H
19
N
N
2. H
+
Bn
Bn
Bn
NHBn
H
H
H
H
H
H
H
290
291
292
O
O
steps
Bn
C
9
H
19
Bn
C
9
H
19
Bn
Bn
(-)-Preussin (
294
)
293
SCHEME 9.50
Synthesis of preussin
294
by Overman and coworkers.
been reported to show antitumor activity against several types of cancer cell lines. In
the synthesis of
300
, hydroquinone
295
was initially oxidized to give sulfinyl quinone
296
that was then reacted with diene
297
to afford the tricyclic derivative
299
in 60%
overall yield and an excellent diastereoselectivity via
(Scheme 9.51) [115].
Interestingly, this transformation was carried out under high pressure similar to
related work within the group on the Diels-Alder reaction/[2,3]-sigmatropic domino
reactions [116]. Hydrogenation and recrystallization completed the synthesis of the
biologically active natural product.
Carreno and coworkers also accomplished the synthesis of the related natural
compounds rubiginones A and B, two terpenes from the angucycline family of
compounds, using a similar approach [117].
In 2003, Mander and Thomson reported a total synthesis of sordaricin (
298
),
the aglycone of the natural product sordarin isolated from
Sordaria araneosa
[118].
304
OH
OH
t-
Bu
O
t-
Bu
O
297
HO
S
HO
S
t-
BuOS
DDQ
CH
2
Cl
2
CH
2
Cl
2
, 12 kbar
O
O
O
60% (2 steps)
H
OH
O
295
296
298
Δ
OH
OH
O
O
1. H
2
, Pd/C, 90%
(
trans
/
cis
= 3:2)
O
O
10
5
2. Crystallization
from MeOH
35%
H
(+)-Royleanone
300
(+)-
299
(ee = 97%)
SCHEME 9.51
Synthesis of royleanone
300
by Carreno and coworkers.
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