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3. 18-oxygenated polyfunctional steroids from the gorgonian
4. Metabolites of the Gorgonian Isis hippuris from India
5. Hippuristerone A (1) was obtained as colorless prisms (14.2 mg), and eluted with n-hexane/EtOAc=4/1; mp 153–154°C; [α]D25 +17° (c 0.5, CHCl3); IR (KBr) νmax 3352, 1726, 1712, and 1252 cm−1; 1H NMR (CDCl3, 500 MHz) δ 4.63 (1H, d, J=10.8 Hz, H-22), 4.03 (1H, dd, J=8.0, 8.0 Hz, H-16), 3.23 (1H, br s, OH-16), 2.35 (1H, ddd, J=15.0, 10.5, 7.0 Hz, H-2β), 2.33 (1H, m, H-2α), 2.31 (1H, m, H-4β), 2.25 (1H, m, H-23), 2.20 (1H, dd, J=8.0, 3.5 Hz, H-15α), 2.12 (3H, s, acetate methyl), 2.10 (1H, m, H-4α), 2.01 (1H, dd, J=5.0, 1.5 Hz, H-1α), 1.98 (3H, s, acetate methyl), 1.94 (1H, q, J=8.0 Hz, H-24), 1.81 (1H, m, H-12β), 1.62 (1H, m, H-11α), 1.59 (1H, m, H-8), 1.58 (3H, s, H3-21), 1.55 (3H, s, H3-26), 1.53 (1H, m, H-5), 1.47 (1H, m, H-12α), 1.44 (3H, s, H3-27), 1.40 (1H, m, H-11β), 1.38 (1H, m, H-15β), 1.36 (1H, m, H-1β), 1.19 (1H, ddd, J=15.0, 8.0, 3.5 Hz, H-14), 1.02 (3H, s, H3-19), 0.96 (3H, s, H3-18), 0.90 (3H, d, J=8.0 Hz, H3-28), 0.86 (3H, d, J=8.0 Hz, H3-29), and 0.79 (1H, dt, J=8.4, 2.8 Hz, H-9); 13C NMR (CDCl3, 125 MHz) δ 211.8 (s, C-3), 171.4 (s, acetate carbonyl), 169.8 (s, acetate carbonyl), 85.6 (s, C-25), 79.4 (s, C-17), 77.2 (d, CH-22), 70.1 (d, CH-16), 67.4 (s, C-20), 53.2 (d, CH-9), 48.4 (d, CH-14), 46.5 (d, CH-5), 44.6 (t, CH2-4), 43.1 (s, C-13), 40.2 (d, CH-24), 38.4 (t, CH2-1), 38.1 (t, CH2-2), 36.3 (t, CH2-12), 35.6 (s, C-10), 34.6 (d, CH-8), 33.5 (d, CH-23), 33.3 (t, CH2-15), 31.4 (t, CH2-7), 28.7 (t, CH2-6), 25.1 (q, CH3-27), 23.0 (q, CH3-26), 22.6 (q, acetate methyl), 21.3 (t, CH2-11), 21.0 (q, acetate methyl), 16.5 (q, CH3-21), 15.5 (q, CH3-18), 11.9 (q, CH3-29), 11.4 (q, CH3-19), and 10.4 (q, CH3-28); FABMS m/z 583 [2 (M+Na)+], 501 (0.7), 483 (2), 441 (2), 423 (2), 371 (3), 341 (6), 313 (5), and 43 (100); HRFABMS 583.3609 (C33H52O7Na, calcd 583.3611).