Reaction Steps
Following the procedure as described in EXAMPLE 9 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 3-methylspiro[furo[3,2-f][1,2]benzisoxazole-5,3′-indol]-2′(1′H)-one, and tert-butyl [5-(bromomethyl)pyridin-2-yl]carbamate to replace 2-(bromomethyl)-5-(trifluoromethyl)furan, tert-butyl {5-[(2′-oxo-2,3-dihydrospiro[furo[2,3-g][1,4]benzodioxine-8,3′-indol]-1′(2′H)-yl)methyl]pyridin-2-yl}carbamate was obtained (74%) as a colorless solid: mp 238-239° C.; 1H NMR (300 MHz, DMSO-d6) δ9.81 (s, 1H), 8.30-8.27 (m, 1H), 7.79-7.73 (m, 1H), 7.73-7.66 (m, 1H), 7.31-7.24 (m, 1H), 7.20-7.14 (m, 1H), 7.12-6.99 (m, 2H), 6.52 (s, 1H), 6.06 (s, 1H), 4.89 (ABq, J=22.9, 15.5 Hz, 2H), 4.74 (ABq, J=44.4, 9.3 Hz, 2H), 4.23-4.05 (m, 4H), 1.45 (s, 9H); 13C NMR (75 MHz, DMSO-d6) δ 176.7, 154.6, 152.6, 151.8, 146.9, 144.1, 141.8, 137.8, 137.2, 131.6, 128.7, 126.2, 123.6, 123.1, 121.1, 112.2, 110.8, 109.3, 98.8, 79.5, 79.3, 64.1, 63.5, 57.2, 27.9; MS (ES+) m/z 502.1 (M+1).
