Identification and total synthesis of a novel dimethylated fatty acid from the caribbean sponge Calyx podatypa

Article abstract of DOI:10.1021/np990529d

The dimethylated fatty acid 9,13-dimethyltetradecanoic acid was identified for the first time in nature in the Caribbean sponge Calyx podatypa where it occurs together with the rare 10,13-dimethyltetradecanoic acid. The characterization of the novel compound was accomplished using GC- MS, pyrrolidide derivatization, and a five-step total synthesis starting with 8-bromooctanoic acid. The first racemic total synthesis for the rare 10,13- dimethyltetradecanoic acid is also described.

Full text of DOI:10.1021/np990529d

6
66
J . Nat. Prod. 2000, 63, 666-669
Id en tifica tion a n d Tota l Syn th esis of a Novel Dim eth yla ted F a tty Acid fr om th e
Ca r ibbea n Sp on ge Ca lyx pod a typa
N e´ stor M. Carballeira* and Mayra Pag a´ n
Department of Chemistry, University of Puerto Rico, P.O. Box 23346, San J uan, Puerto Rico 00931
Received October 20, 1999
The dimethylated fatty acid 9,13-dimethyltetradecanoic acid was identified for the first time in nature
in the Caribbean sponge Calyx podatypa where it occurs together with the rare 10,13-dimethyltetra-
decanoic acid. The characterization of the novel compound was accomplished using GC-MS, pyrrolidide
derivatization, and a five-step total synthesis starting with 8-bromooctanoic acid. The first racemic total
synthesis for the rare 10,13-dimethyltetradecanoic acid is also described.
Marine fatty acids are of interest for the different roles
and biological properties they exhibit in the cells of marine
organisms.1 Some of these fatty acids have displayed
interesting biological activities. For example, short-chain
fatty acids containing 12-16 carbons, mainly of bacterial
origin, display antimicrobial activity against Gram-positive
bacteria.2 On the other hand, longer-chain analogues
diminished peak at m/z 280 with higher than normal
flanking peaks at m/z 266 and m/z 294, and a second
diminished peak at m/z 210 with higher than normal
flanking peaks at m/z 196 and m/z 224. This suggested
5
methyl branching at carbons 9 and 13. The mass spectrum
of N-10,13-dimethyltetradecanoylpyrrolidine displayed simi-
5
lar fragmentations, as had been reported earlier.
5
,9
possessing 26-28 carbons, with the ∆ diunsaturation,
Final structural confirmation for these dimethylated
fatty acids was achieved through their total synthesis. The
best route for the racemic synthesis of methyl 9,13-
dimethyltetradecanoate (1) was achieved through the
coupling reaction of 6-methyl-2-heptanone and (7-meth-
3
are effective as topoisomerase I inhibitors. J ust recently,
we explored the phospholipid fatty acid composition of the
Caribbean sponge Calyx podatypa Van Soest (Phloeodic-
tyidae) and found several novel short-chain fatty acids in
the complex mixture of more than 85 different fatty acids
oxycarbonylheptyl)triphenylphosphonium bromide (Scheme
4
that were characterized. However, at that time we were
7
1
9
5
). The known 6-methyl-2-heptanone was obtained in a
1% yield through the catalytic hydrogenation of 6-methyl-
-hepten-2-one. The salt (7-methoxycarbonylheptyl)tri-
unable to characterize two dimethylated fatty acids due to
their low abundance and close gas chromatographic coelu-
tion of their methyl esters in nonpolar capillary gas
chromatography. Several plausible structural candidates
for these fatty acids can be proposed guided by our
preliminary mass spectral data and biosynthetic consid-
erations. However, the only way left to characterize these
compounds was through their total synthesis followed by
gas chromatographic coelution of the corresponding natural
and synthetic fatty acid methyl esters. We now wish to
report the identification and total synthesis of these two
acids as the novel 9,13-dimethyltetradecanoic acid and the
phenylphosphonium bromide was readily obtained from
commercially available 8-bromooctanoic acid, via esterifi-
cation with HCl/MeOH followed by reaction with triphen-
8
ylphosphine. Coupling of the methylated heptanone with
the Wittig salt resulted in a 73% yield of a 1.4:1 mixture
of the (Z/E)-isomers of methyl 9,13-dimethyl-8-tetradec-
enoate, which upon catalytic hydrogenation afforded the
desired methyl 9,13-dimethyltetradecanoate (1). A GC
coelution experiment with the natural methyl esters dem-
onstrated that the first peak of the two closely related GC
peaks (ECL ) 15.28) indeed corresponded to 1.
To confirm the structure of the other isomer the racemic
synthesis of methyl 10,13-dimethyltetradecanoate (2) was
also undertaken, which is the first reported synthesis for
this compound (Scheme 2). Our synthesis started with
commercially available 9-bromo-1-nonanol (Aldrich), which,
upon reaction with triphenylphosphine, resulted in a 71%
isolated yield of (9-hydroxynonyl)triphenylphosphonium
bromide. Reaction of the latter Wittig salt with 5-methyl-
5
rare 10,13-dimethyltetradecanoic acid. These acids are of
interest because they have the potential to display anti-
microbial activity, inasmuch as the monomethylated ana-
logues 13-methyltetradecanoic acid and 12-methyltetra-
decanoic acid show antimicrobial activity (MIC ) 3.13 µg/
mL) against Streptococcus mutans MT509.6 Herein we
report the results of our investigation.
The fatty acid composition of C. podatypa was previously
reported, and 85 different saturated, methylated, and
4
polyunsaturated fatty acids were identified. In addition,
2
-hexanone, in the presence of potassium t-butoxide in
two dimethylated hexadecanoic acids were not character-
ized due to their low abundance and almost identical
capillary GC elution times (ECL (equivalent-chain length)
values of 15.28 and 15.30). Mass spectrometry of their
pyrrolidide derivatives suggested, although vaguely, that
these compounds could be the unknown 9,13-dimethyltet-
radecanoic acid and the rare 10,13-dimethyltetradecanoic
THF, resulted in a 69% yield of a 1:1 mixture of the Z/E
isomers of 10,13-dimethyl-9-tetradecen-1-ol. In this reac-
tion some minor hydrocarbon products, such as different
Z/E combinations of 2,5,15,18-tetramethyl-5,4-nonadiene,
were also obtained in trace amounts. These hydrocarbon
products could have been formed from a nonane-1,9-
bis(triphenylphosphonium bromide) salt, which was ap-
parently also formed during the preparation of the phos-
phonium salt. However, these hydrocarbons were easily
removed from the alcohol by Si gel column chromatography.
Catalytic hydrogenation of the dimethylated 9-tetradecenol
afforded, in quantitative yield, 10,13-dimethyltetradecan-
5
acid. For example, the mass spectrum of N-9,13-dimeth-
yltetradecanoylpyrrolidine displayed a molecular ion peak
at m/z 309 and two key fragmentations, one with a
*
To whom correspondence should be addressed. Tel.: (787) 764-0000,
ext. 4791. Fax: (787) 756-8242. E-mail: ncarball@upracd.upr.clu.edu.
1
0.1021/np990529d CCC: $19.00
© 2000 American Chemical Society and American Society of Pharmacognosy
Published on Web 03/25/2000

Notes
J ournal of Natural Products, 2000, Vol. 63, No. 5 667
Sch em e 1
Sch em e 2
1
-ol. Interesting to mention at this point is that the related
CDCl
3
(77.0 ppm). Fatty acid methyl esters were analyzed by
trimethylated alcohol, namely the 6,10,13-trimethyltet-
GC-MS at 70 eV using a Hewlett-Packard 5972A MS Chem-
Station equipped with a 30 m × 0.25 mm special performance
capillary column (HP-5MS) of polymethylsiloxane cross-linked
with 5% phenyl methylpolysiloxane. HRMS data was obtained
in a VG AutoSpec high-resolution mass spectrometer.
An im a l Ma ter ia l. C. podatypa Van Soest (class Demospon-
giae, order Haplosclerida, family Phloeodictyidae) was collected
near Mona Island, Puerto Rico, in 1992, at 20 m depth by
scuba. A voucher specimen (no. MI-030) is stored at the
Chemistry Department of the University of Puerto Rico, R ´ı o
Piedras campus.
radecan-1-ol, is the aggregation pheromone of the predatory
stink bug Stiretrus anchorago.9,10 The 10,13-dimethyltet-
radecan-1-ol was further oxidized with pyridinium dichro-
mate in DMF to the expected 10,13-dimethyltetradecanoic
acid, but only trace amounts of the product were isolated.
Final esterification in methanolic HCl afforded enough
methyl 10,13-dimethyltetradecanoate (2) to secure the
structure of the natural compound by GC coelution
(
ECL ) 15.30) with the natural methyl esters from C.
podatypa. We have reported this dimethylated fatty acid
earlier from the sponge Ectyoplasia ferox based on GC and
MS data alone.5
Isola tion a n d Id en tifica tion of F a tty Acid s. The proce-
dure for the extraction and identification of the phospholipid
4
fatty acids from C. podatypa was described previously.
We presented here the identification and racemic syn-
thesis of the methyl ester of a new dimethylated fatty acid,
namely the 9,13-dimethyltetradecanoic acid. We have also
accomplished the first synthesis of the methyl ester of the
6-Meth yl-2-h ep ta n on e. Into a 25-mL round-bottomed flask
were placed 15 mL of distilled MeOH, 0.65 g (5.2 mmol) of
6
2
-methyl-5-hepten-2-one, and catalytic amounts of PtO . The
mixture was allowed to react for 24 h under a hydrogen-filled
balloon. Then, it was filtered and the solvent evaporated in
1
0,13-dimethyltetradecanoic acid, a compound first identi-
vacuo, affording 0.60 g (91% yield) of the known saturated
5
fied in the sponge E. ferox. The elution order of the methyl
esters of these two isomers in nonpolar capillary GC was
also determined. However, the stereochemistry at C-9 and
C-10 in the natural fatty acids will still remain unknown
until a suitable analytical methodology is developed for the
elucidation of the stereochemistry of internally methylated
chiral carbons in fatty acids. Further work is in progress
determining the structures of unusual marine dimethyl-
ated iso-branched fatty acids.
ketone.7
Meth yl 8-Br om oocta n oa te. 8-Bromooctanoic acid (14.7 g,
6
6.2 mmol) and catalytic amounts of HCl were stirred in
refluxing MeOH (25 mL) for 24 h. After this time, the solvent
was removed in vacuo, affording 15.0 g (96% yield) of the
known methyl ester, which was used in the next step without
further purification.8
(
7-Meth oxycar bon ylh eptyl)tr iph en ylph osph on iu m Br o-
m id e. To a stirred solution of triphenylphosphine (9.9 g, 37.6
mmol) in acetonitrile was slowly added methyl 8-bromo-
octanoate (7.6 g, 32.1 mmol). The mixture was refluxed under
nitrogen for 36 h. After cooling, the acetonitrile was removed
in vacuo, and the product was washed extensively with ether
using ultrasound followed by decantation of the solvent to give
Exp er im en ta l Section
Gen er a l Exp er im en ta l P r oced u r es. IR spectra were
1
13
recorded on a Nicolet 600 FTIR spectrophotometer. H and
NMR spectra were recorded on a General Electric Bruker DPX-
C
1
the salt as a clear syrup (14.5 g, 90% yield):
300 MHz) δ 7.87-7.67 (15H, m, -C H ), 3.62 (3H, s, -OCH ),
H NMR (CDCl3,
1
3
00 or -500 spectrometer. H NMR chemical shifts were
6
5
3
1
3
recorded with respect to internal (CH
3
)
4
Si, and C NMR
2.24 (2H, t, J ) 7.4 Hz, H-2), 1.55 (6H, m, H-8, H-7, H-3), 1.25
(6H, m, H-4, H-5, H-6); 13C NMR (CDCl
, 75 MHz) δ 174.2 (s,
chemical shifts are reported in parts per million relative to
3

6
68 J ournal of Natural Products, 2000, Vol. 63, No. 5
Notes
),
C-1), 134.9 (s), 133.8 (d), 133.6 (d), 130.4 (d), 51.4 (q), 33.9 (t),
0.2 (t), 30.0 (t), 28.8 (t), 28.6 (t), 24.7 (t), 23.0 (t); HRFABMS
m/z 499.1228 (calcd for C27 Br-H, 499.1225).
yield): 1H NMR (CDCl
3.59 (2H, t, J ) 6.5 Hz, H-1), 1.62 (2H, br s, H-9), 1.49 (2H, m,
3
, 300 MHz) δ 7.87-7.68 (15H, m, C
6
H
5
3
1
3
H
32PO
2
2 3
H-2), 1.23 (12H, m, CH ); C NMR (CDCl , 75 MHz) δ 135.0
(s), 133.6 (d), 130.5 (d), 130.4 (d), 62.6 (t, C-1), 32.5 (t), 30.2
(t), 28.9 (t), 28.8 (t), 28.7 (t), 25.4 (t), 22.6 (t), 22.5 (t).
Meth yl 9,13-Dim eth yl-8-tetr a d ecen oa te. To a flame-
dried 50-mL three-necked round-bottom flask, equipped with
a pressure-equalizing dropping funnel, a reflux condenser, and
under a nitrogen atmosphere, was added 4.5 mL of anhydrous
t-BuOH and 0.13 g (3.3 mmol) of potassium. After the
potassium t-butoxide precipitated, the excess alcohol was
removed with a double-ended syringe, and the phosphonium
salt (1.6 g, 3.3 mmol), dissolved in THF, was then slowly added.
After 10 min, 6-methyl-2-heptanone (0.09 g, 0.70 mmol) was
also added to the reaction mixture. The reaction was allowed
to stand overnight, and then it was quenched with a saturated
ammonium chloride solution (25 mL), extracted with ether
10,13-Dim eth yl-9-tetr a d ecen -1-ol. This compound was
prepared from (9-hydroxynonyl)triphenylphosphonium bro-
mide (17.0 g, 35 mmol) and 5-methyl-2-hexanone (3.9 g, 34
mmol), in THF, using potassium t-butoxide (7.8 g, 70 mmol)
as base, following the procedure described above for the
synthesis of the other isomer. The desired product [5.6 g, 69%
yield of a 1:1 mixture of (Z/E)-isomers] was obtained after
evaporation of the solvent in vacuo and purification using Si
gel column chromatography (hexane-ether, 8:2): IR (neat) ν
3500-3100 (OH), 2957, 2924, 2858, 1664 (CdC), 1463, 1384,
max
(
2 × 50 mL), and dried over Na
2
SO
4
. After evaporation of the
1367, 1116, 1057, 723 cm-1
; H NMR (CDCl , 300 MHz) δ 5.10
1
3
solvent in vacuo, the crude product was chromatographed on
Si gel, eluting with hexane-ether (8:2, v/v), and this afforded
the desired product [0.13 g, 73% yield of a mixture of 1.4:1
[1H, m, H-9, (E) and (Z)], 3.63 [2H, t, J ) 6.6 Hz, H-1, (E) and
(Z)], 2.00-1.95 [5H, m, H-8, H-11, OH (E) and (Z)], 1.66 [3H,
s, Me-10, (Z)], 1.57 [3H, s, Me-10, (E)], 1.57-1.49 [3H, m, H-2,
(
Z/E)-isomers]: IR (neat) νmax 2958 (dCH), 2930, 2857, 1737
H-13, (E) and (Z)], 1.29-1.19 [12H, m, CH , (E) and (Z)], 0.89-
2
(CdO), 1622, 1465, 1384, 1366, 1261, 1171, 1091, 1024, 876,
0.87 [6H, d, J ) 6.3 Hz, H-14, Me-13, (E) and (Z)]; 13C NMR
-
1 1
8
7
2
06, 725 cm ; H NMR (CDCl
.0 Hz, H-8, (E) and (Z)], 3.66 [3H, s, -OCH
.30 [2H, t, J ) 7.5 Hz, H-2, (E) and (Z)], 1.99-1.90 [4H, m,
3
, 300 MHz) δ 5.09 [1H, t, J )
(CDCl , 75 MHz) δ 135.7 [s, C-10, (E)], 135.4 [s, C-10, (Z)],
3
3
, (E) and (Z)],
124.9 [d, C-9, (E)], 124.3 [d, C-9, (Z)], 63.1 [t, C-1, (E) and (Z)],
37.6 [t, C-11, (E)], 37.4 [t, C-12, (Z)], 37.3 [t, C-12, (E)], 32.8
[t, C-2, (E) and (Z)], 30.1 [t, (E) and (Z)], 29.9 [t, (E) and (Z)],
29.7 [d, C-13, (E) and (Z)], 29.7 [t, C-11, (Z)], 29.5 [t, (E) and
(Z)], 29.4 [t, (E) and (Z)], 29.3 [t, (E) and (Z)], 28.1 [t, C-8, (E)],
27.9 [t, C-8, (Z)], 25.7 [t, (E) and (Z)], 23.5 [q, Me-10, (E) and
(Z)], 22.6 [q, C-14, Me-13, (E) and (Z)]; HREIMS m/z 240.2459
(calcd for C H32O, 240.2453).
H-7, H-10, (E) and (Z)], 1.66 [3H, s, Me-9, (Z)], 1.65 [3H, s,
H-3, H-13, (E) and (Z)], 1.57 [3H, s, Me-9, (E)], 1.36-1.25 [10H,
m, (E) and (Z)], 0.87 [6H, d, J ) 6.6 Hz, H-14, Me-13, (Z)],
0
7
.86 [6H, d, J ) 6.6 Hz, H-14, Me-13, (E)]; 13C NMR (CDCl
5 MHz) δ 174.4 [s, C-1, (E) and (Z)], 135.5 [s, C-9, (Z)], 135.5
,
3
[
-
s, C-9, (E)], 125.0 [d, C-8, (Z)], 124.3 [d, C-8, (E)], 51.4 [q,
OCH , (E) and (Z)], 39.9 [t, C-10, (E)], 38.9 [t, C-10, (Z)], 38.7
1
6
3
1
0,13-Dim eth yl-9(Z)-tetr a d ecen -1-ol:
t
R
) 12.56 min,
[t, C-12, (E)], 38.6 [t, C-12, (Z)], 34.0 [t, C-2, (E) and (Z)], 29.1
[t, (E) and (Z)], 29.0 [t, (E) and (Z)], 28.9 [t, (E) and (Z)], 27.9
[t, C-7, (Z)], 27.7 [t, C-7, (E)], 25.8 [t, (E) and (Z)], 25.7 [t, (E)
+
GC-MS (70 eV) m/z 240 [M ] (9), 185 (1), 156 (1), 123 (11),
1
8
12 (10), 110 (19), 109 (23), 97 (16), 96 (22), 95 (37), 83 (33),
2 (46), 81 (41), 79 (11), 71 (11), 70 (21), 69 (100), 68 (30), 67
and (Z)], 24.9 [t, (E) and (Z)], 23.7 [q, Me-9, (E)], 23.4 [q, Me-
9
(49), 57 (66), 56 (73), 55 (98).
, (Z)], 22.6 [q, C-14, Me-13, (E) and (Z)].
1
0,13-Dim eth yl-9(E)-tetr a d ecen -1-ol:
t
R
) 12.76 min,
Meth yl 9,13-d im eth yl-8(Z)-tetr a d ecen oa te: t
R
) 12.79
+
GC-MS (70 eV) m/z 240 [M ] (9), 185 (1), 151(4), 123 (11),
+
min, GC-MS (70 eV) m/z 268 [M ] (18), 237 (10), 183 (10),
1
1
8
(
12 (10), 110 (20), 109 (23), 97 (15), 96 (22), 95 (37), 83 (34),
2 (49), 81 (42), 79 (10), 71 (11), 70 (21), 69 (100), 68 (32), 67
66 (17), 151 (23), 143 (33), 133 (10), 126 (45), 125 (13), 124
(
(
12), 123 (16), 111 (39), 110 (18), 109 (22), 98 (12), 97 (23), 96
16), 95 (20), 87 (17), 83 (63), 81 (34), 79 (13), 74 (21), 70 (37),
51), 57 (68), 56 (79), 55 (99).
0,13-Dim eth yltetr a d eca n -1-ol. This product was ob-
tained in a 100% yield from the catalytic hydrogenation (PtO
1
6
9 (94), 67 (38), 57 (35), 55 (100).
2
)
Meth yl 9,13-d im eth yl-8(E)-tetr a d ecen oa te: t
R
) 12.99
+
of 10,13-dimethyl-9-tetradecen-1-ol (0.93 g, 3.88 mmol) using
the same procedure as described above for the other isomer:
IR (neat) νmax 3500-3100 (OH), 2960, 2934, 2857, 1464, 1383,
min, GC-MS (70 eV) m/z 268 [M ] (18), 237 (10), 166 (16),
1
51 (21), 143 (20), 126 (41), 125 (11), 124 (11), 123 (14), 111
(
(
35), 110 (17), 109 (20), 98 (11), 97 (21), 96 (15), 95 (19), 87
15), 83 (59), 81 (32), 79 (12), 74 (20), 70 (35), 69 (90), 67 (38),
-
1 1
1
377, 1366, 1116, 1059, 716 cm ; H NMR (CDCl
δ 3.62 (2H, t, J ) 6.6 Hz, H-1), 1.85 (1H, s, -OH), 1.57-1.47
3H, m, H-2, H-13), 1.29-1.07 (19H, m, CH ), 0.86 (3H, d, J )
.6 Hz, H-14), 0.85 (3H, d, J ) 6.6 Hz, Me-13), 0.82 (3H, d,
3
, 300 MHz)
5
7 (34), 55 (100).
Meth yl 9,13-Dim eth yltetr a d eca n oa te (1). Into a 25-mL
(
2
6
round-bottom flask was placed 0.019 g (0.07 mmol) of methyl
,13-dimethyl-8-tetradecenoate in 10 mL of distilled MeOH
together with catalytic amounts of PtO . After 24 h under a
1
3
J ) 6.4 Hz, Me-10); C NMR (CDCl
3
2
3
, 75 MHz) δ 63.0 (t, C-1),
7.0 (t), 36.3 (t), 34.7 (t), 33.0 (t), 32.7 (d), 30.0 (t), 29.6 (t),
9.4 (d), 28.3 (t), 27.1 (t), 25.7 (t), 22.8 (t), 22.6 (q), 19.7 (q);
GC-MS (70 eV) m/z 242 [M ] (0.02), 241 (0.09), 224 (0.2), 210
0.06), 196 (0.5), 181 (0.4), 168 (11), 153 (10), 140 (10), 125
9
2
hydrogen-filled balloon the reaction mixture was filtered and
the solvent evaporated in vacuo, affording the saturated
methyl ester 1 (0.019 g, 100% yield): H NMR (CDCl
MHz) δ 3.66 (3H, s, -OCH ), 2.30 (2H, t, J ) 7.6 Hz, H-2),
1
1
0
1
+
(
1
3
, 500
(
2
15), 112 (15), 97 (39), 83 (39), 69 (48), 57 (100); HREIMS m/z
3
+
24.2499 [M - H
2
O] (calcd for C16
H
32, 224.2504).
.61 (2H, m, H-3), 1.51 (1H, m, H-13), 1.35-1.21 (15H, m),
Meth yl 10,13-Dim eth yltetr a d eca n oa te (2). To a solution
of pyridinium dichromate (2.2 g, 5.9 mmol) dissolved in DMF
20 mL) was added 10,13-dimethyltetradecanol (0.26 g, 1.08
mmol) dissolved in DMF (5 mL). The mixture was allowed to
react for 20 h. The reaction mixture was then quenched with
.14-1.11 (2H, m, H-12), 0.86 (6H, d, J ) 6.6 Hz, Me-13, H-14),
.83 (3H, d, J ) 6.6 Hz, Me-9); 1 C NMR (CDCl
3
3
, 125 MHz) δ
(
3
74.4 (s, CdO), 51.5 (q, -OCH ), 39.3 (t), 37.3 (t), 37.0 (t), 34.1
(t), 32.7 (d, C-9), 29.3 (t), 29.2 (t), 28.1 (t), 28.0 (d, C-13), 27.0
(t), 24.9 (t), 24.8 (t), 22.7 (q, C-14), 22.6 (q, C-15), 19.7 (q, Me-
+
2 4
water, extracted with ether, and dried over Na SO . The
9
); GC-MS (70 eV) m/z 270 [M ] (8), 171 (13), 153 (6), 143
product thus obtained was immediately reacted with catalytic
amounts of HCl in refluxing MeOH (25 mL) for 24 h. After
this time the solvent was removed in vacuo, affording only
traces of the known saturated methyl ester 2 together with
residual aldehyde.5
(16), 135 (6), 115 (7), 111 (8), 101 (9), 97 (13), 86 (62), 83 (16),
7
5 (20), 74 (100), 71 (24), 69 (34), 67 (6), 57 (47), 55 (51).
N-9,13-Dim eth yltetr a d eca n oylp yr r olid in e: GC-MS (70
+
eV) m/z 309 [M] (2), 294 (1), 280 (0.1), 266 (1), 252 (0.3), 238
(
1
(
1), 224 (1), 210 (0.2), 196 (3), 182 (1), 168 (2), 154 (1), 140 (3),
26 (17), 114 (8), 113 (100), 98 (9), 85 (6), 71 (11), 70 (14), 57
8), 56 (7), 55 (19).
9-Hydr oxyn on yl)tr iph en ylph osph on iu m Br om ide. This
Ack n ow led gm en t. This work was supported by the Na-
tional Institutes of Health (NIH) under grant no. 5S06GM08102.
We thank Dr. Abimael D. Rodr ´ı guez (UPR-R ´ı o Piedras) for a
sample of C. podatypa. Mr. Ra u´ l Blanco performed the
HREIMS determinations at the Materials Characterization
Center (MCC).
(
compound was prepared from triphenylphosphine (13.9 g, 53
mmol) and 9-bromo-1-nonanol (11.8 g, 53 mmol), in benzene,
following the same procedure as detailed above for the other
1
1
salt. The salt was obtained as a clear syrup (18.1 g, 71%

Notes
J ournal of Natural Products, 2000, Vol. 63, No. 5 669
Refer en ces a n d Notes
(7) Miller, K. V.; J emiolo, B.; Gassett, J . W.; J elinek, I.; Wiesler, D.;
Novotny, M. J . Chem. Ecol. 1998, 24, 673-683.
(8) Cravatt, B. F.; Lerner, R. A.; Boger, D. L. J . Am. Chem. Soc. 1996,
118, 580-590.
(
(
1) Djerassi, C.; Lam, W.-K. Acc. Chem. Res. 1991, 24, 69-75.
2) Carballeira, N. M.; Reyes, E. D.; Sostre, A.; Rodr ´ı guez, A. D.;
Rodr ´ı guez, J . L.; Gonz a´ lez, F. A. J . Nat. Prod. 1997, 60, 502-504.
3) Nemoto, T.; Yoshino, G.; Ojika, M.; Sakagami, Y. Tetrahedron 1997,
(9) Mori, K.; Wu, J . Liebigs Ann. Chem. 1991, 8, 783-788.
(10) Kochansky, J .; Aldrich, J . R.; Lusby, W. R. J . Chem. Ecol. 1989, 15,
1717-1728.
(
(
5
3, 16699-16710.
4) Carballeira, N. M.; Pag a´ n, M.; Rodr ´ı guez, A. D. J . Nat. Prod. 1998,
1, 1049-1052.
(11) Wang, Q.; He, M.; He, X.; Yuan, G. Rapid Commun. Mass Spectrom.
1997, 11, 1728-1730.
6
(
5) Carballeira, N. M.; Maldonado, M. E. Lipids 1989, 24, 371-374.
6) Hattori, M.; Miyachi, K.; Hada, S.; Kakiuchi, N.; Kiuchi, F.; Tsuda,
Y.; Namba, T. Chem. Pharm. Bull. 1987, 35, 3507-3510.
(
NP990529D