Reaction Steps
Following the procedure as described in EXAMPLE 4 and making non-critical variations using 2,3-dihydrospiro[furo[2,3-g][1,4]benzodioxine-8,3′-indol]-2′(1′H)-one to replace 5,6-dihydrospiro[benzo[1,2-b:5,4-b′]difuran-3,3′-indol]-2′(1′H)-one, and 2-(bromomethyl)pyridine hydrobromide to replace 2-(bromomethyl)tetrahydro-2H-pyran, 1′-(pyridin-2-ylmethyl)-2,3-dihydrospiro[furo[2,3-g][1,4]benzodioxine-8,3′-indol]-2′(1′H)-one was obtained (80%) as a colorless solid: mp 208-209° C. (hexanes); 1H NMR (300 MHz, CDCl3) δ8.58 (d, J=4.8 Hz, 1H), 7.65 (ddd, J=7.7, 7.7, 1.7 Hz, 1H), 7.28-7.15 (m, 4H), 7.02 (dd, J=7.5, 7.5 Hz, 1H), 6.89 (d, J=7.8 Hz, 1H), 6.51 (s, 1H), 6.31 (s, 1H), 5.21 (d, J=16.0 Hz, 1H), 4.97 (d, J=16.0 Hz, 1H), 4.96 (d, J=8.7 Hz, 1H), 4.68 (d, J=8.7 Hz, 1H), 4.22-4.17 (m, 2H), 4.15-4.10 (m, 2H); 13C NMR (75 MHz, CDCl3) δ 177.6, 155.6, 155.3, 149.6, 144.6, 142.2, 138.3, 137.1, 132.2, 128.9, 123.8, 123.5, 122.8, 121.6, 121.1, 111.8, 109.6, 99.4, 80.2, 64.5, 63.9, 58.2, 46.1; MS (ES+) m/z 387.2 (M+1).
