Biology Reference
In-Depth Information
The oxidized macrocyclic dimer eugeniflorin D
2
(
86
, Lee
et al.
,
1997) also deserves special mention, for it features a dehydrovaloneoyl
group. It was isolated from
Eugenia uniflora
together with eugeniflorin
D
1
, a regular macrocyclic dimer (see Chapter 1). Similarly, oenotherin T
1
(
87
), isolated from
Oenothera tetraptera
, is a dehydro-derivative of
trimer oenothein A found in
Oenothera
erythrosepala
and
Oenothera
biennis
(Yoshida
et al.
, 1991c). Interestingly, the cyclohexenetrione
moiety in
87
can be reduced to a valoneoyl group under mild conditions
to give oenothein A (Taniguchi
et al.
, 2002).
GO
GO
O
O
GO
GO
OG
OG
OH
GO
GO
OH
O
O
OH
OH
O
O
OH
OH
O
OH
HO
OH
O
HO
OH
HO
HO
OH
HO
OH
O
O
O
O
OG
O
O
OG
O
O
O
O
Euphorbin B (
88
)
Euphorbin I (
89
)
O
O
O
O
O
O
O
O
H
H
O
HO
OH
OH
O
HO
OH
OH
OH
OH
HO
O
HO
O
OH
G =
OH
R'O
OH
O
O
O
OH
RO
O
OH
GO
OH
O
OH
O
HO
OH
O
(
S
)-HHDP =
O
O
HO
OH
O
O
O
HO
OH
HO
OH
OG
HO
OH HO
OH
O
O
O
Euphorbin C (
90
): R,R' = (
S
)-HHDP
Euphorbin D (
91
): R = R' = G
O
O
O
O
H
O
HO
OH
OH
OH
HO
O
