Chemistry Reference
In-Depth Information
H
3
CO
OCH
3
H
3
CO
OCH
3
H
3
C
H
3
C
O
H
3
C
CH
3
MeOH, HC(OMe)
3
O
O
O
O
O
+
N
O
NH
D-manno
-
64
Cl
CH
3
CH
3
60
82
83
only one stereoisomer
6-deoxy-L-allo-nojirimycin
1.) CbzCl, NaHCO
3
2.) OsO
4
, NMO
H
3
CO
OCH
3
OH
HO
HO
OH
O
N
HO
Cbz
HO
H
CH
3
CH
3
84
85
35% over 3 steps
99%ee
Scheme 4.13
Preparation of nojirimycin derivatives using hetero-Diels-Alder reactions with
60
as key step.
D-xylose
D-xylo
1.) HO-NH
3
Cl
H
2
O, NaHCO
3
2.) tBu-OCl, C
H
2
Cl
2
TBDPSO
TBDPSO
HO
Cl
HO
O
O
O
OH
O
O
O
O
N
O
CH
3
CH
3
CH
3
CH
3
OH
O
86
87
88
69% from D-xylose (
86
)
ent
-epibatadine
H
2
N
N
Cl
Cl
4
O
87
+
N
CHCl
3
, iPrOH, H
2
O
95%
ent
-
66
ent
-
89
94%, 96%ee
88
ent
-physoperuvine
CH
3
H
2
N
N
Cl
O
90
+
87
CHCl
3
, iPrOH, H
2
O
OH
93%
91
ent
-
92
93%, 96%ee
Scheme 4.14
Heterodienophile
88
in the preparation of
ent
-epibatadine (
ent
-
89
) and
ent
-physoperuvine (
ent
-
92
).
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