Marine antitumor agents: 14-deoxycrassin and pseudoplexaurol, new cembranoid diterpenes from the Caribbean gorgonianPseudoplexaura porosa

Faulkner, D. J., Nat. Prod. Rep.8 (1991) 97; and previous papers in the series.

Ciereszko, L. S., and Karns, T. K. B., Comparative Biochemistry of Coral Reef Coelenterates, in: Biology and Geology of Coral Reefs, pp. 183–203. Eds O. A. Jones and R. Endean. Academic Press, New York 1973.

Ciereszko, L. S., Sifford, D. S., and Weinheimer, A. J., Ann. N. Y. Acad. Sci.90 (1960) 917.

Weinheimer, A. J., and Matson, J. A., Lloydia38 (1975) 378.

Pettit, G. R., Day, J. F., Hartwell, J. L., and Wood, H. B., Nature227 (1970) 962.

IR (neat)v max 3436, 2932, 2865, 1720, 1617, 1445, 1378, 1264, 1180, 1132, 1096, 1031, 954, 790 cm−1; LREIMSm/z (%) 318(5), 300(4), 275(5), 241(3), 219(3), 193(11), 147(21), 133(26), 121(36), 107(52), 93(60), 81(100), 67(62), 55(80).

1H-NMR (300-MHz, CDCl3) δ 6.40 (1H, d, J=2.1 Hz, H-17α), 5.59 (1H, d, J=2.1 Hz, H-17β), 5.09 (1H, m), 5.02 (1H, t,J=7.5 Hz), 3.96 (1H, d,J=10.2 Hz), 2.32–1.60 (broad envelope), 1.57 (3H, s), 1.53 (3H, s), 1.35 (3H, s), 1.33–1.10 (broad envelope).

The1H−1H COSY spectrum of3 showed the following cross peaks (partial list): H-17α/H-17β, H-13/H-14, H-14/H-1, H-1/H-2, H-2β/H-3, H-7/H-6, H-7/Me-19, H-11/H-10, H-11/Me-20.

The Selective INEPT spectrum of3 showed the following2,3JCH correlations (partial list): H-17α/C-16, C-15 and C-1; H-17β/C-16 and C-1; H-7/C-6 and C-19; H-11/C-10 and C-20; H-3/C-1; H-19/C-7 and C-8; H-20/C-11 and C-12; H-18/C-4 and C-3.

Booth, H., Tetrahedron Lett.7 (1965) 411.

Weinheimer, A. J., Matson, J. A., Hossain, M. B., and Van der Helm, D., Tetrahedron Lett.34 (1977) 2923.

Ravi, B. N., and Faulkner, D. J., J. org. Chem.43 (1978) 2127.

IR (neat)v max 3425, 2961, 2923, 2871, 1650, 1445, 1384, 1259, 1236, 1109, 1095, 1061, 1029, 896, 801 cm−1; LREIMSm/z (%) 304(3), 286(1), 273(2), 187(2), 161(7), 159(6), 133(22), 119(27), 107(38), 93(53), 91(42), 81(76), 67(61), 55(100).

The Selective INEPT spectrum of4 showed the following2,3JCH correlations (partial list): H-17αβ/C-1, C-15 and C-16; H-16/C-15, C-17 and C-1; H-3/C-2 and C-5; H-18/C-3, C-4 and C-5.

Carlsen, P. H. J., Katsuki, T., Martin, V. S., and Sharpless, K. B., J. org. Chem.46 (1981) 3936.