반응 단계
Following the procedure as described in EXAMPLE 7 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 spiro[furo[2,3-f][1,3]benzodioxole-7,3′-indol]-2′(1′H)-one, and methyl 5-(chloromethyl)-2-furoate to replace 4-methoxybenzyl chloride, methyl 5-[(2′-oxo-2,3-dihydrospiro[furo[2,3-g][1,4]benzodioxine-8,3′-indol]-1′(2′H)-yl)methyl]furan-2-carboxylate was obtained (92%) as a colorless solid: mp 88-92° C. (hexanes/diethyl ether); 1H NMR (300 MHz, CDCl3) δ7.28 (ddd, J=7.8, 7.5, 1.2 Hz, 1H), 7.17 (dd, J=7.2, 0.9 Hz, 1H), 7.12 (d, J=3.6 Hz, 1H), 7.06 (ddd, J=7.8, 7.8, 0.9 Hz, 1H), 6.96 (d, J=7.8 Hz, 1H), 6.50 (s, 1H), 6.37 (d, J=3.6 Hz, 1H), 6.24 (s, 1H), 5.12 (d, J=16.5 Hz, 1H), 4.91 (d, J=9.0 Hz, 1H), 4.90 (d, J=16.5 Hz, 1H), 4.64 (d, J=9.0 Hz, 1H), 4.22-4.18 (m, 2H), 4.14-4.10 (m, 2H), 3.89 (s, 3H); 13C NMR (75 MHz, CDCl3) δ177.2, 158.9, 155.3, 153.4, 144.8, 144.4, 141.4, 138.4, 132.2, 129.1, 124.1, 123.9, 120.9, 119.1, 111.7, 110.3, 109.1, 99.5, 80.1, 64.6, 64.0, 58.1, 52.1, 37.4; MS (ES+) m/z 433.9 (M+1).
