Reaction Steps
Following the procedure as described in EXAMPLE 4 and making non-critical variations using 2-(chloromethyl)-3-fluoropyridine hydrochloride to replace 2-(bromomethyl)tetrahydro-2H-pyran, and (8S)-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, (8S)-1′-[(3-fluoropyridin-2-yl)methyl]-2,3-dihydrospiro[furo[2,3-g][1,4]benzodioxine-8,3′-indol]-2′(1′H)-one was obtained (33%) as a colorless solid: mp 125-126° C. (diethyl ether); 1H NMR (300 MHz, CDCl3) 8.38-8.32 (m, 1H), 7.43-7.34 (m, 1H), 7.28-7.11 (m, 3H), 7.02-6.95 (m, 1H), 6.78 (d, J=7.6 Hz, 1H), 6.48 (s, 1H), 6.44 (s, 1H), 5.31 (d, J=16.2 Hz, 1H), 5.04 (d, J=16.2 Hz, 1H), 4.95 (d, J=8.9 Hz, 1H), 4.67 (d, J=8.9 Hz, 1H), 4.21-4.07 (m, 4H); 13C NMR (75 MHz, CDCl3) δ 177.5, 159.6, 156.2, 155.2, 145.4, 144.5, 142.9, 142.8, 142.2, 138.3, 132.6, 128.6, 124.3, 123.8, 123.3, 123.1, 121.3, 112.2, 109.0, 99.2, 80.2, 64.5, 63.9, 58.1, 40.7; MS (ES+) m/z 404.9 (M+1). Anal. Calcd. for C23H17FN2O4: C, 68.31; H, 4.24; N, 6.93. Found: C, 67.27; H, 4.24; N, 6.93.
