(-)-Axinyssene: A novel cytotoxic diterpene from a Japanese marine sponge Axinyssa sp

Article abstract of DOI:10.1021/ol027202f

(Matrix presented) A novel diterpene, (-)-axinyssene, was isolated from the Japanese marine sponge Axinyssa sp. The structure of (-)-axinyssene was determined on the basis of spectroscopic and synthetic evidence to be 1-methyl-4-[(4E)-5′9′-dimethyl-1′-methylene-4′, 8′-decadienyl]-(4S)-cyclohexene. (-)- and (+)-axinyssene showed mild cytotoxicity against acute promyelocytic leukemia, HL-60 cells.

Full text of DOI:10.1021/ol027202f

ORGANIC
LETTERS
2003
Vol. 5, No. 2
169-171
(−)-Axinyssene: A Novel Cytotoxic
Diterpene from a Japanese Marine
Sponge Axinyssa sp
,†
Kota Kodama,† Ryuichi Higuchi,† Tomofumi Miyamoto,* and
Rob W. M. Van Soest‡
Graduate School of Pharmaceutical Sciences, Kyushu UniVersity,
Maidashi 3-1-1, Higashi-ku, Fukuoka 812-8582, Japan,
and Institute for BiodiVersity and Ecosystem Dynamics,
UniVersity of Amsterdam, P.O. Box 94766, 1090 GT Amsterdam, Netherlands
miyamoto@phar.kyushu-u.ac.jp
Received October 30, 2002
ABSTRACT
A novel diterpene, (−)-axinyssene, was isolated from the Japanese marine sponge Axinyssa sp. The structure of (−)-axinyssene was determined
on the basis of spectroscopic and synthetic evidence to be 1-methyl-4-[(4E)-5′,9′-dimethyl-1′-methylene-4′,8′-decadienyl]-(4S)-cyclohexene.
(−)- and (+)-axinyssene showed mild cytotoxicity against acute promyelocytic leukemia, HL-60 cells.
Marine sponges have proved to be a rich source of secondary
metabolites with unusual structures as well as interesting
biological activities. In the last few decades, it is not unusual
to suggest that most of the bioactive compounds might be
produced by symbiotic microorganisms.1 Sponges of the
genus Axinyssa have been reported to yield a variety of
sesquiterpene, isocyanides, thiocyanates, isothiocyanates,
formamides, and carbonimide dichlorides.2 In the course of
our continuing research on biologically active compounds
from Japanese marine invertebrates, we have investigated
the isolation for the cytotoxic principle from the marine
sponge Axinyssa sp. We report here the isolation and
structure elucidation of a new diterpene, (-)-axinyssene (1).
Axinyssa sp. (wet weight ) 289 g) was collected by hand
at depths of 10 m off Tsutsumi Island, Fukuoka prefecture,
Japan, in September, 1996.3 The n-hexane-soluble fraction
(2.02 g) of the acetone extract obtained from Axinyssa sp.
showed cytotoxicity against HL-60 cells at 33 µg/mL.
Bioassay guided the separation of the active fraction by
Sephadex LH-20, silica gel chromatography (n-hexane/
EtOAc), and reversed-phase HPLC to give an active com-
pound, (-)-axinyssene (1, 1.4 mg), together with four
known sesquiterpenes, isothiocyanate4 (2, 10.1 mg), (+)-
axisothiocyanate 25 (3, 9.8 mg), and epipolasin A6 (4, 7.4
mg).
† Kyushu University.
‡ University of Amsterdam.
(1) Faulkner, D. J. J. Nat. Prod. Rep. 2002, 19, 1-48 and previous reports
in this series.
(2) (a) Marcus, A. H.; Molinski, T. F.; Fahy, E.; Faulkner, D. J. J. Org.
Chem. 1989, 54, 5184. (b) He, H.-Y.; Salva´, J.; Catalos, R. F.; Faulkner,
D. J. J. Org. Chem. 1992, 57, 3191. (c) Patil, A. D.; Freyer, A. J.; Reichwein,
R.; Bean, M. F.; Faucette, L.; Johnson, R. K.; Haltiwanger, R. C.; Eggleston,
D. S. J. Nat. Prod. 1997, 60, 507. (d) Hirota, H.; Okino, T.; Yoshimura,
E.; Fusetani, N. Tetrahedron 1998, 54, 13971. (e) Li, C.-J.; Schmitz, F. J.;
Kelly, M. J. Nat. Prod. 1999, 62, 1330. (f) Petrichtcheva, D. V.; Duque,
C.; Duenas, A.; Zea, S.; Hara, N.; Fujimoto, Y. J. Nat. Prod. 2002, 65,
851.
(3) Axinyssa sp.: Class Demospongiae, order Astrophorida, family
Ancorinidae. A voucher specimen was deposited in the Zoological Museum
in University of Amsterdam (ZMA Por 17060).
10.1021/ol027202f CCC: $25.00 © 2003 American Chemical Society
Published on Web 12/24/2002

Figure 3. Intensive fragment peaks in EIMS of 1.
ethylenediamine (TMEDA) complex and geranyl bromide,8
and (+)- and (-)-axinyssene were obtained in 68.2 and
66.4% yields, respectively.9
Figure 1. Structure of (-)-axinyssene (1) and sesquiterpenes.
(-)-Axinyssene (1)7 was obtained as a colorless oil. The
The specific rotation of 1 showed an unreliable value due
to the small quantity of material available; therefore, optical
resolution with a chiral HPLC was applied for determination
of the absolute configuration of 1.10 The synthesized (+)-
and (-)-axinyssenes were subjected to chiral HPLC and
showed retention times at 7.31 min for (+)-axinyssene and
at 7.08 min for (-)-axinyssene, respectively. The retention
time at 7.06 min for natural axinyssene was in good
agreement with that of (-)-axinyssene. Accordingly, the
structure of 1 was determined to be (-)-axinyssene (1-
methyl-4-[(4E)-5′,9′dimethyl-1′-methylene-4′,8′-decadienyl]-
(4S)-cyclohexene).
1
EIMS showed the molecular ion peak at m/z 272. The H
and 13C NMR and HSQC spectral data suggested the
presence of four olefinic methyls, eight methylenes, one
methine, three trisubstituted olefines, and one vinyl. From
the above data, the molecular formula of 1 was suggested
to be C20H32. The 1H-1H COSY and HMBC spectra afforded
partial structures as shown in Figure 2. Furthermore, these
The cytotoxic activity of axinyssenes was evaluated by
the MTT method. The IC50 values of axinyssenes against
HL-60 cells were 16.9 µg/mL (1, natural), 12.1 µg/mL [(+)-
axinyssene], and 9.6 µg/mL [(-)-axinyssene]. The (+)- and
(-)-axinyssenes did not differ significantly in their cytotox-
icity.
The carbon framework of (-)-axinyssene (1) has not been
described and may be biosynthesized via geranyl-geranyl-
diphosphate directly.
(7) Axinyssene (natural, 1): colorless oil; IR (CHCl3, cm-1) 2927, 1456,
1377, 891; EIMS (m/z) 272(M+), 257, 204, 187, 69 (base peak); 1H NMR
(500 MHz, CDCl3) δ 1.48(1H, m, H5), 1.60(6H, s, H10′, H12′), 1.65(3H,
s, H7), 1.68(3H, s, H13′), 1.81(1H, m, H3), 1.94(2H, m, H6′), 1.98(2H, m,
H6), 2.03(2H, m, H7′), 2.05(1H, m, H4), 2.08(2H, m, H3), 4.74(2H, d, J )
6.9, H11′), 5.10(1H, t, J ) 6.2, H8′), 5.14(1H, t, J ) 6.4, H4′), 5.41(1H,
br.s, H2); 13C NMR (125.0 MHz, CDCl3) δ 133.7(s, C1), 120.8(d, C-2),
31.4(t, C3), 39.8(d, C4), 28.4(t, C5), 30.8(t, C6), 23.4(q, C7), 154.3(s, C1′),
34.9(t, C2′), 26.8(t, C3′), 124.2(d, C4′), 135.1(s, C5′), 39.7(t, C6′), 26.8(t,
C7′), 124.4(d, C8′), 131.3(s, C9′), 17.7(q, C10′), 107.1(t, C11′), 16.0(q,
C12′), 25.7(q, C-13′).
Figure 2. Significant correlations in DQF-COSY and PFG-HMBC
spectra of 1.
three partial structures were merged by the aid of the analysis
of EIMS fragmentation as shown in Figure 3.
(8) Suemune, H.; Kawahara, T.; Sakai, K. Chem. Phram. Bull. 1986,
34, 550.
(9) (+)-Axinyssene: colorless oil; [R]D +34.6° (c 0.2, CHCl3). Anal.
Calcd for C20H32: C, 88.16; H, 11.84. Found: C, 87.74; H, 12.35. EIMS
(m/z) 272(M+); 13C NMR (125.0 MHz, CDCl3) δ 133.7(C1), 120.9(C2),
31.5(C3), 39.9(C4), 28.3(C5), 30.8(C6), 23.4(C7), 154.3(C1′), 34.9(C2′),
26.8(C3′), 124.3(C4′), 135.1(C5′), 39.7(C6′), 26.8(C7′), 124.4(C8′), 131.2-
(C9′), 17.7(C10′), 107.2(C11′), 16.0(C12′), 25.7(C13′).
To determine the absolute configuration of 1, (+)- and
(-)-axinyssene were synthesized from the commercially
available limonene and geraniol. The C-10 position of (+)-
and (-)-limonene was alkylated with sec-BuLi-tetamethyl-
(10) (-)-Axinyssene: colorless oil; [R]D -34.2° (c 0.2, CHCl3). Anal.
Calcd for C20H32: C, 88.16; H, 11.84. Found: C, 87.78; H, 12.25. EIMS
(m/z) 272(M+); 13C NMR (125.0 MHz, CDCl3) δ 133.7(C1), 120.8(C2),
31.5(C3), 39.8(C4), 28.4(C5), 30.8(C6), 23.4(C7), 154.3(C1′), 34.9(C2′),
26.8(C3′), 124.2(C4′), 135.1(C5′), 39.7(C6′), 26.7(C7′), 124.4(C8′), 131.3-
(4) Ciminello, P.; Fattorusso, E.; Magno, S.; Mayol, L. Can J. Chem.
1987, 65, 518.
(5) Fattorusso, E.; Magno, S.; Mayol, L.; Santacroce, C.; Sica, D.
Tetrahedron 1975, 31, 269.
1
(C9′), 17.7(C10′), 107.2(C11′), 16.0(C12′), 25.7(C13′); for H NMR data,
(6) Capon, R.; MacLeod, J. Aust. J. Chem. 1988, 41, 979.
see Supporting Information.
170
Org. Lett., Vol. 5, No. 2, 2003

Scheme 1. Synthesis of (+)- and (-)-Axinyssenes
Acknowledgment. We thank Dr. Mary Garson, The
Supporting Information Available: 1H NMR spectra
of natural, synthesized (+)- and (-)-axinyssenes and
two-dimensional NMR spectra of (-)-axinyssenes. This
material is available free of charge via the Internet at
http://pubs.acs.org.
University of Queensland, for reading the manuscript. Mr.
M. Kinoshita and Captain Y. Shichida, of the Fishery
Research Laboratory, Kyushu University are gratefully
acknowledged for assistance with sample collections. This
work was supported in part by a Grant-in-Aid for Scientific
Research (C) (No. 12672055) from The Ministry of Educa-
tion, Sciences, Sports and Culture, Japan.
OL027202F
Org. Lett., Vol. 5, No. 2, 2003
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