Reaktionsschritte
[α]D +41.3° (MeOH, c 5.2); UV λmax (ε) 242 (4963), 280 (2430), 286 (2212); IR (neat) νmax 3402, 3270, 2960, 1748, 1724, 1676, 1514, 1466, 1343, 1239, 1177 cm-1 ; EIMS m/z (rel intensity) 640/642 (66/27), 398/400 (47/16), 265 (55), 227 (93), 181 (100); high resolution EIMS m/z 640.25676 (calcd for C34H41ClN2O8, -1.6 mmu error). 1H NMR (CDCl3): amino or hydroxyacid unit δ (carbon position, multiplicity; J in Hz) 7,8-epoxy-5-hydroxy--6-methyl-8-phenyl-2-octenoic acid (A) 5.74 (2, d; 16), 6.67 (3, ddd; 15.3, 9.7 and 5.5), .45 (4, dt; 14.3 and 10.4), 2.55 (4, brdd; 14.3 and 5.3), 5.15 (5, ddd; 11.2, 4.8 and 1.8), 1.8 (6, m), 1.14 (6-Me, d; 7.0), 2.92 (7, dd; 7.5 and 2.0), 3.69 (8, d; 2.0), 7.24-7.26 (10/14, m), 7.33-7.39 (11/12/13, m); 3-chloro-4-hydroxyphenylalanine (B) 4.8 (2, m), 5.64 (2-NH, d; 8.8), 3.03 (3, dd; 14.5 and 7.0), 3.11 (3, dd; 14.4 and 5.6), 7.17 (5, d; 2.2), 5.61 (7-OH, s), 6.91 (8, d; 8.3), 7.0 (9, dd; 8.3 and 2.2); 3-amino-2-methylpropionic acid (C) 2.7 (2, m), 1.22 (2-Me, d; 7.3), 3.28 (3, dt; 13.6 and 6.8), 3.49 (3, ddd; 13.6, 5 and 4.1), 6.92 (3-NH, br t; 6.1); leucic acid (D) 4.83 (2, dd; 10.1 and 3.3), 1.36 (3, m), 1.67-1.75 (3, m), 1.67-1.75 (4, m), 0.85 (5, d; 7.5), 0.86 (5', d; 6.8). 13C NMR (CDCl3) unit δ (carbon position) A 165.3 (1), 125.3 (2), 141.0 (3), 36.7 (4), 76.2 (5), 40.6 (6), 13.5 (6-Me), 63.0 (7), 59.0 (8), 136.8 (9), 125.6 (10/14), 128.7 (11/13), 128.6 (12); B 170.9 (1), 53.6 (2), 35.1 (3), 129.9 (4), 129.6 (5), 120.0 (6), 150.4 (7), 116.4 (8), 129.2 (9), C 175.6 (1), 38.3 (2), 14.1 (2-Me), 41.1 (3); D 170.8 (1), 71.3 (2), 39.4 (3), 24.6 (4), 21.3 (5), 22.9 (5').
