BOX 1: EM015 was obtained as white crystals in 83% yield (4.49 g). m.p. 169.0-169.1°C; 1H NMR (CDCl3, 400 MHz): δ 7.14 (d, 1H, J = 8.26 Hz), 6.41 (d, 1H, J = 8.26 Hz), 5.93 (s, 2H), 5.27 (d, 1H, J = 4.31 Hz), 4.20 (d, 1H, J = 4.32 Hz), 3.99 (s, 3H), 3.87 (s, 3H), 3.83 (s, 3H), 2.79-2.65 (m, 2H), 2.54-2.46 (m, 2H), 2.35 (s, 3H); 13C NMR (CDCl3, 100 MHz): δ 167.7, 152.4, 147.5, 139.3, 134.9, 126.1, 120.3, 118.4, 108.5, 102.3, 93.5, 81.9, 64.2, 61.8, 59.6, 57.7, 46.1, 45.2, 39.8, 20.6, 18.6; high-resolution mass spectra (electrospray ionization; ESI): m/z calculated for C22H23O7NCl (M+1), 448.11481; found, 448.11482 (M+1).