Chemistry Reference
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COOMe
R
1
R
1
No. R
1
R
2
No. R
1
R
2
79 H OH
80 H AcO
81 OH H
82 =O
R
2
R
2
75 H OH
76 H AcO
77 OH H
78 =O
O
O
O
O
Figure 6-7
An unidentified Japanese species of the same genus yielded several cembranoids
(75-78), all having seven-membered lactone systems. Their structures were
elucidated based on spectral data and chemical correlations.
40
Several other
seven-membered cembranoid lactones, (1E,3E,8S,11Z)-4,8-dimethyl-1-isopropyl-
7-oxo-cyclotetradeca-1,3,11-triene and its 7R and 7S-hydroxyderivative (79-82),
were isolated from an Australian species (Figure 6-7).
41
Two novel irregular cembranoids possessing a 13-membered carbocyclic skele-
ton, sarcotol (83), and sarcotal acetata (84) were reported from another unidentified
Sarcophyton species (Figure 6-8), whose structures were determined by spectro-
scopic and single-crystal x-ray analyses and chemical conversion.
42,43
Two new cytotoxic tetraterpenes, methylsarcophytotate (85) and methylchloro-
sarcophytoate (86), were isolated from the species of Japanese seawater.
44
Another
novel tetraterpenoid, methylisosartortuate (88), was reported being isolated from
S. tortuosum; its structure was determined by spectral data and confirmed by
x-ray studies.
45
The same species yielded one more unique tetracyclic tetraterpe-
noid, methylsartortuate (89), and its structure was confirmed by x-ray diffraction.
46
A new biscembranoid, methylneosartotuate (87), and a novel bisepoxidecembra-
noid 66 along with a known compound, methylsarcoate (65), were isolated from
an Australian species of S. tortuosum; their structures were elucidated by 1-D
and 2-D NMR spectral data.
35
A unique new tetraterpenoid 90 was also isolated
from the Chinese species S. tortuosum, and its structure was established by compa-
rison of its spectra with its derivatives (Figure 6-9).
47
OH
OH
O
O
OH
AcO
Sarcotol (
83
)
Sarcotal acetate (
84
)
Figure 6-8
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