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Tetrahedron Letters
Volume 27, Issue 2, 1986, Pages 223-226

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Chlorovulones, new halogenated marine prostanoids with ...
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Chlorovulones, new halogenated marine prostanoids with an antitumor activity from the stolonifer clavularia viridis Quoy and Gaimard
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doi:10.1016/S0040-4039(00)83982-9

Determination of absolute configuration of chlorovulones by cd measurement and by enantioselective synthesis of (−)-chlorovulone II¹

Hiroto Nagaoka, Kazuo Iguchi, Tohru Miyakoshi, Nobuko Yamada and Yasuji Yamada, ^*

Tokyo College of Pharmacy, 1432-1 Horinouchi, Hachioji, Tokyo 192-03, Japan

Received 1 October 1985.

Available online 8 March 2001.

Abstract

Absolute configuration of chlorovulones, new halogenated marine prostanoids with an antitumor activity isolated from the stolonifer Clavularia viridis Quoy and Gaimard, has been established on the basis of the CD measurement of the chlorovulone derivatives and of the enantioselective synthesis of (−)-chlorovulone II.

References

This paper constitutes Part XIII of “Studies on Marine Natural Products.”.

K.Iguchi, S.Kaneta, K.Mori, Y.Yamada, A.Honda, and Y.Mori, Tetrahedron Lett., in press.

All new compounds have been fully characterized by IR, ¹H-NMR(400 MHz), and high resolution mass spectroscopy and/or combustion analysis.

[α_D +4.7°(c 0.17,CHCl₃); UV(EtOH) 247nm( var epsilon 4,500); ¹H-NMR(400 MHz.CDCl₃) δ 2.02(3H,s), 2.35(1H,dd,J=6.5,13.7 Hz,H-11_β), 2.83(1H,dd,J=10.7,13.7 Hz,H-11α), 3.66(3H,s), 3.85(1H, brd, D₂O exchangeable), 4.08(1H,ddd,J=4.6,6.5,10.7 Hz,H-10), 4.25(1H,br,H-9), 5.79(1H,td, J=7.1,14.3Hz), 6.40(2H,m).

[α]_D −42.7°(c 0.15,CHCl₃), UV(EtOH) 248nm( var epsilon 7,200); ¹H-NMR(400 MHz,CDCl₃) δ 2.02(3H,s), 2.43(1H,dd,J=7.3,12.9 Hz,H-11_β), 2.60(1H,dd,J=11.5,12.9 Hz,H-11_α), 3.66(3H,s), 3.79(1H, ddd,J=7.3,8.7,11.5 Hz,H-10), 4.80(1H,brd,J=8.7 Hz,H-9), 5.75(1H,td,J=7.3,14.5 Hz), 6.21 (1H,dd,J=2.3,11.5 Hz), 6.43(1H,dd,J=11.5,14.5 Hz). Oxidation of each alcohol with PCC gave the same dienone 19, showing that 6 and 7 are epimeric at the C-9 position. The relative stereochemistries between C-9 and C-IO for 6 and 7 were suggested by the coupling constants between H-9 and H-IO, respectively.

N. Harada, J. Iwabuchi, Y. Yokota, H. Uda and K. Nakanishi J.Am.Chem.Soc. 103 (1981), p. 5590. Full Text via CrossRef | View Record in Scopus | Cited By in Scopus (52)

[α]_D +40°(c 0.035,CHCl₃); UV(EtOH) 247nm( var epsilon 20,700); ¹H-NMR(400 MHz, CDCl₃) δ 5.68(1H,d, J=4.4 Hz,H-9), 7.60(2H,d,J=8.6 Hz), 7.99(2H,d,J=8.6 Hz).

[α]_D −41°(c 0.022,CHCl₃); UV(EtOH) 248nm( var epsilon 20,700); 1H-NMR(400 MHz,CDCl₃) δ 6.16(1H,d, J=7.1 Hz,H-9), 7.60(2H,d,J=8.4 Hz), 7.93(2H,d,J=8.4 Hz).

Chlorovulone IV (4) was not isolated as a pure state and its structure was suggested on the basis of the spectra of its correspondi0ng acetate². The same absolute configuration of 4 as those of chlorovulone I, II and III was indicated by the formation of chlorovulone IV acetate in the photoisomerization reaction of 5. (fluorescent lamp, C₆H₆).

H. Nagaoka, T. Miyakoshi and Y. Yamada Tetrahedron Lett. 25 (1984), p. 3621. Abstract | PDF (201 K) | View Record in Scopus | Cited By in Scopus (13)

H.Nagaoka, T.Miyakoshi, J.Kasuga and Y.Yamada, Tetrahedron Lett., in press.

K. Ogura, M. Yamashita and G. Tsuchihashi Tetrahedron Lett. (1976), p. 759. Abstract | PDF (202 K) | View Record in Scopus | Cited By in Scopus (13)

[α]_D −40.2(c 0.90,CHCl₃); ¹H-NMR(400 MHz,CDCl₃) 0.88(3H,t,J=6.8 Hz), 2.00(2H,dd,J=7.3, 14.1 Hz), 2.58(1H,d,J=18.8 Hz), 2.79(1H,d,J=18.8 Hz), 3.37(3H,s), 4.62(1H,d,J=7.6 Hz), 4.69(1H,d,J=7.6 Hz), 5.34(1H,m), 5.59(1H,m), 7.39(1H,s).

The ester aldehyde 16 was prepared by the sequence (1) methanolysis of δ-valerolactone (MeONa, MeOH, rt), (2) oxidation of primary hydroxyl group (DMSO, (COCl)₂, CH₂Cl₂, −78° C, and then Et₃N, −78° C to 0° C), (3) Wittig reaction (Ph₃P=CHCHO, ClCH₂CH₂Cl, 80° C).

[α]_D +14.5° (c 0.6, CHCl₃); ¹H-NMR(400 MHz,CDCl₃) δ 0.87(3H,t,J=6.8 Hz), 2.65(1H,dd,J=8.3,14.1 Hz), 2.78(1H,dd,J=6.8,14.1 Hz), 3.36(3H,s), 3.67(3H,s), 4.45(2H,s), 5.26(1H,m), 5.51(1H,m), 6.27(1H,td,J=7.0,15.1 Hz), 6.66(1H,tdd,J=1.3,11.8,15.1 Hz), 7.08(1H,d,J=11.8 Hz), 7.23(1H,s).

H. Kikuchi, Y. Tsukitani, K. Iguchi and Y. Yamada Tetrahedron Lett. 23 (1982), p. 5171. Abstract | PDF (291 K) | View Record in Scopus | Cited By in Scopus (57)
H. Kikuchi, Y. Tsukitani, K. Iguchi and Y. Yamada Tetrahedron Lett. 24 (1983), p. 1549. Abstract | PDF (204 K) | View Record in Scopus | Cited By in Scopus (39)
Erratum; Expression of the absolute configuration at C-12 of clavulones as R in the reference 14b should be read as S. See also the references for claviridenones; M. Kobayashi, T. Yasuzawa, M. Yoshibara, H. Akutsu, Y. Kyogoku and I. Kitagawa Tetrahedron Lett. 23 (1982), p. 5331. Abstract | PDF (291 K) | View Record in Scopus | Cited By in Scopus (30)
M. Kobayashi, T. Yasuzawa, M. Yoshihara, B.W. Son, Y. Kyogoku and I. Kitagawa Chem. Pharm. Bull. 31 (1983), p. 1440. View Record in Scopus | Cited By in Scopus (5)

Tetrahedron Letters
Volume 27, Issue 2, 1986, Pages 223-226

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