Reaction Steps
Following the procedure as described in EXAMPLE 4 and making non-critical variations using 2-chloro-5-(chloromethyl)thiophene to replace 2-(bromomethyl)tetrahydro-2H-pyran, and 4′-chlorospiro[furo[2,3-f][1,3]benzodioxole-7,3′-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, 4′-chloro-1′-[(5-chloro-2-thienyl)methyl]spiro[furo[2,3-f][1,3]benzodioxole-7,3′-indol]-2′(1′H)-one was obtained (67%) as a colorless solid: mp 167-168° C. (diethyl ether/hexanes); 1H NMR (300 MHz, DMSO-d6) δ 7.36 (dd, J=8.0, 8.0 Hz, 1H), 7.20-7.18 (m, 2H), 7.08 (dd, J=8.0, 0.7 Hz, 1H), 6.77 (d, J=3.4 Hz, 1H), 6.66 (s, 1H), 6.12 (s, 1H), 5.94 (s, 2H), 5.09 (ABq, 2H), 4.92 (d, J=9.8 Hz, 1H), 4.75 (d, J=9.8 Hz, 1H); 13C NMR (75 MHz, DMSO-d6) δ 176.1, 156.2, 148.5, 143.3, 141.5, 137.5, 130.5, 129.8, 127.8, 127.7, 127.3, 126.5, 123.6, 116.5, 108.3, 102.4, 101.4, 92.9, 77.0, 57.8, 38.7; MS (ES+) m/z 446.2 (M+1), 448.2 (M+1).
