July 2002
939
4
0)
41)
were analyzed with the diol 12 as the standard compound. In sized by reaction of (C H ) AsCH COCH(CH ) Br with the aldehyde 15
6
5
3
2
3 2
4
2)
43)
(
Chart 2) followed by aqueous acid treatment. Compound 11 was pre-
contrast with the saturated alcohol 2, the saturated ketone 6
formed an Na adduct ion, as did the enone 7 (Fig. 3). Even
ϩ
pared from the aldehyde 15 by reaction with (C H ) PϭCHCOOCH to af-
6
5
3
3
ford the a,b-unsaturated ester, followed by aqueous acid treatment. Com-
pound 5 was obtained by reduction of the a,b-unsaturated ester described
so, the intensity value of the enone 7 (1.00) was higher than
that of the ketone 6 (0.57), and the difference may reflect the above with diisobutylaluminum hydride, followed by aqueous acid treat-
4
4,45)
relative strength of the coordination of the carbonyl group ment. Compound 10
was obtained by esterification of cholenic acid
16 (purchased from Steraloids Inc. Wilton, NH, U.S.A., Chart 2) with
trimethylsilyldiazomethane. Compound 4 was prepared by LiAlH re-
duction of compound 10. Compound 3 was obtained by reduction of 5a-
cholest-1-en-3-one with NaBH in the presence of CeCl .
ϩ
and olefinic double bond of 7 to Na , as compared with 6
Chart 1c). The higher value of the enone 9 (1.00) than the
ketone 8 (0.84) in group 4, and also that of the unsaturated
4
6)
47)
4
(
4
8)
49)
50,51)
All com-
4
3
1
ester 11 (1.00) compared with the ester 10 (0.88) support the pounds prepared were characterized by H-NMR (JEOL JNM A-500 NMR
coordination of the olefinic double bond and the carbonyl spectrometer, 500 MHz) and FAB mass spectrometry.
1
ϩ
H-NMR (CDCl ) of 3: d 0.64 (3H, s), 0.84 (3H, d, Jϭ6.5 Hz), 0.85 (3H,
group to Na .
3
d, Jϭ6.5 Hz), 0.88 (3H, d, Jϭ6.0 Hz), 0.89 (3H, s), 4.28 (1H, dddd, Jϭ9.0,
In conclusion, steroidal allylic alcohols, a,b-unsaturated
7
1
.0, 1.5, 1.5 Hz), 5.46 (1H, ddd, Jϭ10.0, 1.5, 1.5 Hz), 5.90 (1H, dd, Jϭ10.0,
.5 Hz). 4: d 0.66 (3H, s), 0.92 (3H, d, Jϭ6.5 Hz), 0.99 (3H, s), ca. 3.5 (1H,
ion peaks in FAB mass spectrometry. The adduct ions were m), ca. 3.6 (2H, m), 5.33 (1H, m). 5: d 0.68 (3H, s), 0.99 (3H, s), 1.02 (3H,
ϩ
ketones and an a,b-unsaturated ester afforded Na adduct
d, Jϭ6.5 Hz), 3.35 (1H, m), 4.04 (2H, m), 5.33 (1H, m), 5.53 (2H, m). 9: d
0.70 (3H, s), 0.99 (3H, s), 1.08 (9H, d, Jϭca. 7.0 Hz), 3.51 (1H, m), 5.33
1H, m), 6.05 (1H, d, Jϭ15.5 Hz), 6.70 (1H, dd, Jϭ15.5, 9.0 Hz). 10: d 0.66
3H, s), 0.91 (3H, d, Jϭ6.7 Hz), 0.99 (3H, s), 3.50 (1H, m), 3.64 (3H, s),
suggested to be formed by coordination of the olefinic dou-
ϩ
ble bond and the proximal oxygen function to Na , in which
(
(
5
the cation-p interaction plays an important role. Participation
ϩ
of the olefinic double bond in the stabilization of Na adduct
.33 (1H, m). 11: d 0.70 (3H, s), 0.99 (3H, s), 1.07 (3H, d, Jϭ6.5 Hz), 3.50
ions of type b and c in Chart 1 may be attributed to the delo- (1H, m), 3.70 (3H, s), 5.33 (1H, m), 5.73 (1H, d, Jϭ15.5 Hz), 6.82 (1H, dd,
Jϭ15.5, 9.0 Hz).
calization of positive charge. In this regard, Adams and Gross
studied the lithiation of mono-unsaturated oleyl alcohol, find-
References and Notes
ing that the spatially separated hydroxyl group and olefinic
1) Barber M., Bordoli R. S., Sedgwick R. D., Tyler A. N., Nature (Lon-
don), 293, 270—275 (1981).
2) Williams D. H., Bradley C., Bojesen G., Santikarn S., Taylor L. C. E.,
J. Am. Chem. Soc., 103, 5700—5704 (1981).
ϩ
double bond were unable to form a complex with Li , and
3
3)
that the double bond was not lithiated. Rubino et al. sug-
gested the participation of olefinic p-electrons and a hy-
3
4
)
)
Watson J. T., “Biological Mass Spectrometry,” ed. by Matsuo T.,
Caprioli R. M., Gross M. L., Seyama Y., John Wiley & Sons, 1994,
pp. 23—40.
ϩ 34)
droxyl group of sphingosine to form a complex with Li .
Addition of sodium salt to allylic alcohols to form stable
ϩ
Pramanik B. N., Das P. R., Bose A. K., J. Nat. Prod., 52, 534—546
[
MϩNa] ion peaks will be useful in molecular weight de-
(
1989).
termination in FAB mass spectrometry.
5
6
7
)
)
)
Teesch L. M., Adams J., Org. Mass Spectrom., 27, 931—943 (1992).
Fujii T., Mass Spectrom. Rev., 19, 111—138 (2000).
Morisaki N., Inoue K., Kobayashi H., Shirai R., Morisaki M., Iwasaki
S., Tetrahedron, 52, 9017—9024 (1996).
Experimental
Instrumentation and Sample Preparation FAB mass spectra were
recorded on a JEOL JMS-HX110 double-focusing mass spectrometer of
EBE arrangement with a JMS-DA7000 data system. The ion acceleration
voltage was 10 kV, and xenon gas was accelerated at a voltage of 6 kV. m-Ni-
trobenzyl alcohol (mNBA) was used as the matrix, and NaCl was used as the
sodium cation source. The CAD spectrum was obtained with helium as the
collision gas, which was metered to cause about 20% attenuation of the main
beam.
8
9
)
Zhou Z., Ogden S., Leary L. A., J. Org. Chem., 55, 5444—5446
(
1990).
)
Orlando R., Bush C. A., Fenselau C., Biomed. Environ. Mass Spec-
trom., 19, 747—754 (1990).
1
1
0) Brüll L. P., Kovacik V., Thomas-Oates J. E., Heerma W., Haverkamp J.,
Rapid Commun. Mass Spectrom., 12, 1520—1532 (1998).
1) Sawada M., Shizuma M., Takai Y., Yamada H., Tanaka T., Okumura
Y., Hidaka Y., Hanafusa T., Takahashi S., Bull. Chem. Soc. Jpn., 65,
1275—1279 (1992).
Sample solutions for the FAB mass analyses, containing 0.5 equivalents
of NaCl, were prepared by mixing 5 ml each of 0.1 M sample compound in
7
)
CHCl –CH OH (1 : 1), 0.05 M NaCl in H O–CH OH (1 : 9) and mNBA. So-
3
3
2
3
1
2) Johnstone R. A. W., Rose M. E., J. Chem. Soc., Chem. Commun.,
lutions for experiments to obtain the relative intensities of sodium adduct
1
983, 1268—1270 (1983).
ions were prepared by mixing 5 ml each of 0.1 M test compound and 0.1 M
7
)
13) Maleknia S., Brodbelt J., J. Am. Chem. Soc., 114, 4295—4298 (1992).
14) Chu I-H., Zhang H., Dearden D. V., J. Am. Chem. Soc., 115, 5736—
standard compound [hexadecene-1,2-diol (12), 5a-cholestane-1a,3b-diol
7
,30,31)
7,32)
(
0
13),
or (20R,22R)-cholest-5-ene-3b,20,22-triol (14) ], 10 ml of
5
744 (1993).
.02 M NaCl, and 10 ml of mNBA. An aliquot of the mixture was applied to
1
1
5) Lattimer R. P., J. Am. Soc. Mass Spectrom., 5, 1072—1080 (1994).
6) Leary J. A., Zhou Z., Ogden S. A., Williams T. D., J. Am. Soc. Mass
Spectrom., 1, 473—480 (1990).
the target tip for FAB mass analyses. FAB mass spectra were obtained by
means of a 5.2 s scan from m/z 10 to 1900. Three values at 20, 30, and 40 s
from the start of the scanning, were averaged. Each sample was measured at
least twice.
1
1
7) Grese R. P., Gross M. L., J. Am. Chem. Soc., 112, 5098—5104 (1990).
8) Teesch L. M., Orlando R. C., Adams J., J. Am. Chem. Soc., 113,
Materials The structures of compounds 1—11 and standard compounds
3
668—3675 (1991).
1
2—14 are listed in Table 1. 5a-Cholestan-3b-ol (2) and m-NBA were pur-
1
9) Cerda B. A., Hoyau S., Ohanessian G., Wesdemiotis C., J. Am. Chem.
Soc., 120, 2437—2448 (1998).
chased from Tokyo Kasei Kogyo Co., Ltd. 5a-Cholestan-3-one (6) and 1,2-
hexadecanediol (12) were purchased from Sigma Chemical Co. and Aldrich
Chemical Co., Inc., respectively. Compounds 1,
3
5,36)
37)
38)
30,31)
20) Dougherty D. A., Science, 271, 163—168 (1996).
21) Ma J. C., Dougherty D. A., Chem. Rev., 97, 1303—1324 (1997).
7, 8, 13,
and
3
2)
39)
1
4
were prepared by the reported methods. Compound 9 was synthe-
2
2
2
2
2
2) Sunner J., Nishizawa K., Kebarle P., J. Phys. Chem., 85, 1814—1820
1981).
3) Guo B. C., Purnell J. W., Castleman A. W., Chem. Phys. Lett., 168,
55—160 (1990).
4) Armentrout P. B., Rodgers M. T., J. Phys. Chem. A, 104, 2238—2247
2000).
5) Caldwell J. W., Kollman P. A., J. Am. Chem. Soc., 117, 4177—4178
1995).
(
1
(
(
6) Nicholas J. B., Hay B. P., Dixon D. A., J. Phys. Chem. A, 103, 1394—
Chart 2
1400 (1999).