Chemistry Reference
In-Depth Information
O
O
O
Me
O
Me
25
25
O
Guanidinium nitrate (
4
)
O
OBn
OBn
AcO
OTBS
NaOMe, MeOH-CH
2
Cl
2
HO
OTBS
14
100
101
Dess-Martin ox.
90% (2 steps)
Ph
Ph
Ph
Ph
O
O
Me
25
O
O
O
B
OBn
OTBS
H
14
OTBS
+
1
13
O
OTBS
OTBS
OTBS
CH
2
Cl
2
55%
O
Me
O
25
O
OTBS
OBn
1
OTBS
14
13
OTBS
OTBS
OTBS
OH
102
H
2
(1500 psi)
(
S
)-Ru-(BINAP)(OAc)
2
88%
OH
HO
HO
OH
OH
OH
O
H
H
H
OH
OH
O
OH
H
OH
HO
Me
OH
OH
OH
Me
OH
1
25
OH
OH
OH
OH
OH
OH
amphidinol 3 (
103
)
Scheme 7.21
Synthetic studies on amphidinol 3 (103)
reacted with iodine in the presence of TMG (3) to give gem-diiodide. This diiodide was
treated with DBU to afford the vinyl iodide 127 [41]. After conversion of 127 to the maleate
derivative 128, radical cyclization afforded 129, which was led to the natural product
griseolic acid B 130 (Scheme 7.28).
