Reaction Steps
Following the procedure as described in EXAMPLE 4 and making non-critical variations using 2-(bromomethyl)pyridine to replace 2-(bromomethyl)tetrahydro-2H-pyran, and spiro[furo[3,2-e][2,1,3]benzoxadiazole-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, 1′-(pyridin-2-ylmethyl)spiro[furo[3,2-e][2,1,3]benzoxadiazole-8,3′-indol]-2′(1′H)-one was obtained (81%) as a colorless solid: mp 180-182° C.; 1H NMR (300 MHz, CDCl3) δ8.63-8.59 (m, 1H), 7.84 (d, J=9.6 Hz, 1H), 7.77-7.70 (m, 1H), 7.57 (d, J=7.8 Hz, 1H), 7.32 (d, J=9.6 Hz, 1H), 7.28-7.16 (m, 3H), 7.04 (ddd, J=7.5, 7.5, 0.9 Hz, 1H), 6.88 (d, J=7.8 Hz, 1H), 5.45 (d, J=16.2 Hz, 1H), 5.28 (d, J=9.6 Hz, 1H), 5.01 (d, J=9.6 Hz, 1H), 4.92 (d, J=16.2 Hz, 1H); 13C NMR (75 MHz, CDCl3) δ176.1, 163.0, 155.1, 149.4, 148.3, 144.9, 142.2, 137.3, 129.8, 129.7, 123.7, 123.67, 122.8, 121.9, 121.6, 119.4, 110.1, 107.0, 82.0, 57.4, 46.5; MS (ES+) m/z 371.0 (M+1).
