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I
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[30] Selected data for compound 22: Rf = 0.35 (EtOAc/hexanes =
5:1); [a]2D0 (CH3OH, c = 0.69) = ꢀ277.25; IR (film): n˜max = 3260,
2919, 1713, 1660, 1602, 1496, 1443, 1401, 1302, 1261, 1214, 1155,
1055, 750 cmꢀ1; 1H NMR (600 MHz, CD3CN): d = 10.38 (s, 1H),
8.42 (s, 1H), 7.54 (d, J = 7.9 Hz, 1H), 7.42–7.33 (m, 7H), 7.27
(brm, 1H), 7.22 (d, J = 7.0 Hz, 1H), 7.10 (d, J = 7.4 Hz, 1H),
6.89–6.87 (m, 2H), 6.82 (t, J = 7.9 Hz, 1H), 6.77 (d, J = 7.9 Hz,
1H), 6.73 (s, 1H), 6.15 (d, J = 7.9 Hz, 1H), 5.08 (AB quart, J =
12.7 Hz, n˜AB = 17.1 Hz, 2H), 4.55 (t, J = 7.4 Hz, 1H), 4.24 (ddd,
J = 11.4, 8.8, 3.1 Hz, 1H), 3.23 (t, J = 12.7 Hz, 1H), 2.68 (d, J =
11.4 Hz, 1H), 2.00 (m, 1H), 1.01 (d, J = 6.1 Hz, 3H), 0.91 ppm (d,
J = 6.1 Hz, 3H); 13C NMR (150 MHz, CDCl3): d = 174.9, 173.8,
164.3, 156.3, 154.6, 152.9, 152.8, 143.2, 140.6, 138.0, 135.9, 134.5,
131.6, 130.6, 130.0, 129.4, 129.3, 128.8, 128.6, 128.2, 127.2, 126.9,
124.8, 124.5, 123.2, 122.7, 116.6, 112.4, 98.3, 67.0, 57.8, 57.0, 56.4,
37.8, 31.0, 19.6, 19.0 ppm; HRMS (MALDI): calcd for
C43H32Cl2N6O7+: 815.1782 [MþH+], found: 815.1778.
1758
ꢀ 2003 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Angew. Chem. Int. Ed. 2003, 42, 1753 – 1758