Chemistry Reference
In-Depth Information
OH
OAc
OAC
steps
steps
O
OH
122
143
O
a
b
O
176
27
Reagents and Conditions: (a) i. K
2
CO
3
, MeOH; ii. PCC, CH
2
Cl
2
; (b) TiCl
4
/Zn, THF, reflux, 25 h.
Scheme 6-18
class of oxidative metabolites of cembrene diterpenes. (
รพ
)-11,12-epoxycembrene C
(28), a novel cembrane epoxide, was first isolated in 1978 by Bowden et al. from
the Australian soft coral Sinularia grayi
99
and was subsequently found in various
marine soft coral, that is, Nephthea spp.,
100
Lobophytum spp.,
101
Eunicea spp.,
102
Sinularia spp.,
103
and Sarcophyton spp. Its structure was determined by means of
extensive spectroscopic techniques and chemical degradation. (
)-7, 8-epoxycem-
brene C (33) was first isolated in 1980 by Bowden et al. from the soft coral
OAc
OAc
O
O
a
PhO
2
S
O
+
O
Cl
X
179
X = SO
2
Ph
180
X = H
177
178
O
b
c
O
176
27
Reagents and Conditions: (a) n-BuLi, THF,
40
C; (b) i. Na(Hg), Na
2
HPO
4
, MeOH; ii. K
2
CO
3
, MeOH;
iii. p-TsOH, MeOH; iv. PCC, CH
2
Cl
2
; (c) TiCl
4
/Zn, THF, reflux, 25 h.
Scheme 6-19
Search WWH ::
Custom Search