Reaction Steps
[α]D +68.1° (MeOH, c 0.075); UV λmax (ε) 246 (25500), 284 (5200); IR (neat) νmax 3401, 3282, 2962, 1744, 1728, 1668, 1540, 1505, 1464, 1258, 1198, 1177, 1066, 694 cm-1 ; EIMS m/z (rel intensity) 624/626 (0.8/0.3), 398/400 (43/14), 227(78), 195/197 (58/26) 91 (100); high resolution EIMS m/z 624.2650 (calcd for C34H41ClN2O7, -4.8 mmu error); 1H-NMR(CDCl3):amino or hydroxy acid unit δ (carbon position, multiplicity; J in Hz) 5-hydroxy-6-methyl-8-phenyl-2,7-octadienoic acid (A) 5.77 (2, d; 14.1), 6.67 (3, m), 2.38 (4, m), 2.50 (4, m), 5.01 (5, m), 2.56 (6, m), 1.13 (6-Me, d; 6.5), 6.03 (7, dd; 15.8 and 8.6), 6.42 (8, d; 15.8), 7.29-7.35 (10/11/13/14, m), 7.23 (12; m); 3-chloro-4-methoxyphenylalanine (B) 4.82 (2, m), 5.64 (2-NH, m), 3.06 (3, m), 3.13 (3, m), 7.22 (5, m), 3.87 (7-OMe, s), 6.83 (8, m), 7.08 (9, m); 3-amino-2-methylpropionic acid (C) 2.72 (2, m), 1.22 (2-Me, d; 6.7), 3.26 (3, m), 3.53 (3, m), 6.90 (3-NH, m); 2-hydroxyvaleric acid (D) 4.81 (2, dd; 8.8 and 3.9), 1.63 (3, m), 1.68 (3, m), 1.33 (4-H2, m). 0.74 (5, t; 7.3).
