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3012.
3.0 Hz, 1H), 2.34 (m, 1H), 1.97–1.43 (m, 6H), 0.97 (t, J = 7.3 Hz, 3H), 0.95 (d,
J = 6.8 Hz, 3H), 0.88 (d, J = 6.8 Hz, 3H), 0.84 (s, 9H), 0.05 (s, 3H), ꢀ0.04 (s, 3H);
13C NMR (CDCl3, 75 MHz): d 200.0, 164.8, 150.9, 142.9, 141.2, 136.1, 130.9,
129.0, 128.7, 127.2, 126.8, 120.9, 84.7, 73.7, 42.9, 36.7, 36.4, 35.7, 31.4, 25.8,
22.6, 20.1, 17.9, 14.6, 13.3, 10.9, ꢀ4.7; HRMS (ESIMS): Calcd for C31H46O4NaSi
[M+Na]+: 533.3063. Found: 533.3048; Analytical and spectral data of
compound 7: Rf = 0.32 (SiO2, 20% EtOAc in petroleum ether);
ð½a 2D2
ꢂ
= ꢀ180.66 (c 0.14, CHCl3); IR (neat): vmax 3474 (br), 2924, 2868, 1715,
1615, 1585, 1458, 1382, 1252 and 1060 cmꢀ1
;
1H NMR (CDCl3, 500 MHz): d
7.51–7.43 (m, 2H), 7.42–7.28 (m, 4H), 7.05 (dd, J = 9.8, 6.8 Hz, 1H), 7.01 (d,
J = 15.7 Hz, 1H), 6.87 (dd, J = 14.7, 10.8 Hz, 1H), 6.27 (d, J = 15.7 Hz, 1H), 6.04 (d,
J = 9.8 Hz, 1H), 3.96 (dd, J = 10.8, 2.9 Hz, 1H), 3.92 (m, 1H), 2.82 (dd, J = 16.7,
2.0 Hz, 1H), 2.66 (dd, J = 16.7, 9.8 Hz, 1H), 2.34 (m, 1H), 1.95 (m, 1H), 1.84–1.66
(m, 3H), 1.65–1.47 (m, 2H), 1.00 (t, J = 7.8 Hz, 3H), 0.95 (d, J = 5.9 Hz, 3H), 0.91
(d, J = 5.9 Hz, 3H); 13C NMR (CDCl3, 150 MHz): d 201.7, 165.1, 151.3, 143.8,
142.3, 135.8, 129.6, 129.4, 128.9, 127.4, 126.4, 121.0, 85.0, 72.3, 42.3, 36.7,
35.0, 31.2, 22.6, 20.2, 14.5, 14.1, 10.8; HRMS (ESIMS): Calcd for C25H32O4Na
[M+Na]+: 419.2198. Found: 419.2197; Analytical and spectral data of
compound (ꢀ)-Bitungolide E: Rf = 0.46 (SiO2, 40% EtOAc in petroleum ether);
ð½a 2D2
ꢂ
= ꢀ104.82 (c 0.2, CHCl3); IR (neat): vmax 3404 (br), 2960, 2924, 2855,
1713, 1459, 1384, 1258, and 1059 cmꢀ1
;
1H NMR (CDCl3, 500 MHz): d 7.39 (br
d, J = 7.3 Hz, 2H), 7.31(t, J = 7.3 Hz, 2H), 7.22 (br t, J = 7.3 Hz, 1H), 7.08 (dd,
J = 6.6, 9.5 Hz, 1H), 6.78 (dd, J = 10.3, 15.4 Hz, 1H), 6.56 (br d, J = 15.4 Hz, 1H),
6.46 (dd, J = 10.3, 15.4 Hz, 1H), 6.04 (d, J = 9.6 Hz, 1H), 5.90 (dd, J = 5.9, 15.4 Hz,
1H), 4.63–4.57 (m, 1H), 3.97 (dd, J = 2.9, 10.3 Hz, 1H), 3.80 (m, 1H), 2.36 (m,
1H), 1.95 (m, 1H), 1.80 (m, 2H), 1.70 (m, 1H), 1.60–1.40 (m, 2H), 1.40–1.39
(m,1H), 1.25–1.17 (m, 1H), 0.96 (d, J = 7.3 Hz, 3H), 0.91 (d, J = 6.6 Hz, 3H), 0.89
(t, J = 6.6 Hz, 3H); 13C NMR (CDCl3, 75 MHz): d 164.9, 151.2, 136.1, 132.6, 130.3,
128.6, 128.2, 127.5, 126.3, 120.9, 85.0, 73.3, 70.4, 38.8, 36.7, 36.1, 35.2, 31.0,
20.1, 14.7, 14.6, 11.0; HRMS (ESIMS): calcd for C25H34O4Na [M+Na]+: 421.2354.
Found: 421.2347.
15. (a) Evans, D. A.; Chapman, K. T. Tetrahedron Lett. 1986, 27, 5939; (b) Evans, D.
A.; Chapman, K. T.; Carriera, E. M. J. Am. Chem. Soc. 1988, 110, 3560.
16. Analytical and spectral data of compound 28: Rf = 0.43 (SiO2, 15% EtOAc in
petroleum ether); ð½a D22
= ꢀ112.20 (c 0.14, CHCl3); IR (neat): vmax 2926, 2855,
ꢂ
1722, 1616, 1589, 1461, 1382, 1250, and 1062 cmꢀ1; 1H NMR (CDCl3, 300
MHz): d 7.53–7.42 (m, 2H), 7.42–7.27 (m, 4H), 7.08 (dd, J = 9.8, 6.0 Hz, 1H),
7.02–6.82 (m, 2H), 6.29 (d, J = 15.1 Hz, 1H), 6.05 (d, J = 9.8 Hz, 1H), 4.14 (m, 1H),
3.94 (dd, J = 9.8, 3.0 Hz, 1H), 2.85 (dd, J = 14.3, 8.3 Hz, 1H), 2.44 (dd, J = 14.3,