Reaction Steps
Yellow powder; mp 75-76° C.; UV (MeOH) λmax (log ε) 368 (4.09), 206 (4.08) nm; IR (NaCl) γmax 3395, 2921, 1635 cm−1; 1H NMR (CD3OD, 500 MHz) δ 1.63 (3H, s, H-5″), 1.77 (3H, s, H-4″), 3.34 (2H, d, J=7.2 Hz, H-1″), 5.26 (1H, m, H-2″), 6.53 (1H, d, J=8.8 Hz, H-5′), 6.92 (2H, d, J=8.5 Hz, H-3), 7.72 (2H, d, J=8.4 Hz, H-2), 7.74 (1H, d, J=15.2 Hz, H-1), 7.82 (1H, d, J=15.3 Hz, H-β), 7.96 (H, d, J=8.9 Hz, H-6′); 13C NMR (CD3OD, 125 MHz) δ 17.9 (C-4″), 22.2 (C-1″), 25.8 (C-5″), 107.9 (C-5′), 114.4 (C-1′), 116.0 (C-3′), 116.7 (C-3), 118.5 (C-α), 123.2 (C-2″), 127.6 (C-1), 130.3 (C-6′), 131.5 (C-3″), 131.7 (C-2), 144.9 (C-β), 160.9 (C-4), 162.6 (C-4′), 164.7 (C-2′), 192.5 (CO); EIMS m/z 324 (M+, 100), 281 (83), 269 (22), 176 (22) 161 (36), 149 (96), 120 (31).
