Reaction Steps
Following the procedure as described in EXAMPLE 4 and making non-critical variations using (S)-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, (S)-1′-(pyridin-2-ylmethyl)-2,3-dihydrospiro[furo[2,3-g][1,4]benzodioxine-8,3′-indol]-2′(1′H)-one was obtained (95%) as a colorless solid: mp 144-146° C. (diethyl ether/hexanes); 1H NMR (300 MHz, CDCl3) δ8.59 (dd, J=5.1, 0.6 Hz, 1H), 7.73 (ddd, J=7.8, 7.5, 1.5 Hz, 1H), 7.33-7.27 (m, 2H), 7.22 (ddd, J=7.7, 7.7, 1.3 Hz, 1H), 7.17 (dd, J=7.4, 0.9 Hz, 1H), 7.03 (ddd, J=7.5, 7.5, 0.9 Hz, 1H), 6.95 (d, J=7.8 Hz, 1H), 6.51 (s, 1H), 6.29 (s, 1H), 5.26 (d, J=15.9 Hz, 1H), 5.04 (d, J=15.9 Hz, 1H), 4.96 (d, J=9.0 Hz, 1H), 4.68 (d, J=9.0 Hz, 1H), 4.22-4.18 (m, 2H), 4.15-4.11 (m, 2H); 13C NMR (75 MHz, CDCl3) δ177.7, 155.4, 155.3, 148.6, 144.8, 142.0, 138.4, 138.2, 132.2, 129.0, 124.0, 123.7, 123.3, 122.3, 121.1, 111.8, 109.7, 99.5, 80.3, 64.6, 64.0, 58.2, 45.5; MS (ES+) m/z 387.0 (M+1).
