Reaction Steps
Following the procedure as described in EXAMPLE 12 and making non-critical variations using 2,4-dimethylaniline to replace cyclohexanemethylamine, and 4-[(2′-oxo-5,6-dihydrospiro[benzo[1,2-b:5,4-b′]difuran-3,3′-indol]-1′(2′H)-yl)methyl]benzoic acid to replace 3-[(2′-oxo-5,6-dihydrospiro[benzo[1,2-b:5,4-b′]difuran-3,3′-indol]-1′(2′H)-yl)methyl]benzoic acid, N-(2,4-dimethylphenyl)-4-[(2′-oxo-5,6-dihydrospiro[benzo[1,2-b:5,4-b']difuran-3,3′-indol]-1′(2′H)-yl)methyl]benzamide was obtained (59%) as a colorless solid: mp 249-251° C.; 1H NMR (300 MHz, CDCl3) δ7.91-7.83 (m, 2H), 7.76-7.69 (m, 1H), 7.56 (s, 1H), 7.50-7.43 (m, 2H), 7.28-7.17 (m, 2H), 7.09-7.01 (m, 3H), 6.80-6.74 (m, 1H), 6.49 (s, 1H), 6.44 (s, 1H), 5.03 (ABq, 2H), 4.86 (ABq, 2H), 4.60-4.51 (m, 2H), 3.11-2.92 (m, 2H), 2.32 (s, 3H), 2.28 (s, 3H); 13C NMR (75 MHz, CDCl3) δ 178.0, 165.2, 161.9, 161.3, 141.7, 139.6, 135.3, 134.6, 132.9, 132.6, 131.2, 129.8, 128.7, 127.7, 127.4, 124.0, 123.6 (2C), 120.0 (2C), 118.8, 109.1, 93.3, 80.6, 72.4, 57.7, 43.8, 29.0, 20.9, 17.8; MS (ES+) m/z 517.2 (M+1).
