1-(diphenylmethyl)-3-(7-hydroxy-2,3-dihydro-1,4-benzodioxin-6-yl)-4,6-dimethoxy-1,3-dihydro-2H-indol-2-one 、
1-(diphenylmethyl)-3-(2-hydroxy-4-methoxy-5-methylphenyl)-1,3-dihydro-2H-indol-2-one 以1′-(diphenylmethyl)-4′,6′-dimethoxy-2,3-dihydrospiro[furo[2,3-g][1,4]benzodioxine-8,3′-indol]-2′(1′H)-one was obtained (96%) as a colorless solid的产率得到1'-(diphenylmethyl)-4',6'-dimethoxy-2,3-dihydrospiro[furo[2,3-g][1,4]benzodioxine-8,3'-indol]-2'(1'H)-one