1'-(4-hydroxybenzyl)-5,6-dihydrospiro[benzo[1,2-b:5,4-b']difuran-3,3'-indol]-2'(1'H)-one 、
1'-(3-hydroxybenzyl)-5,6-dihydrospiro[benzo[1,2-b:5,4-b']difuran-3,3'-indol]-2'(1'H)-one 以2-{4-[(2′-oxo-5,6-dihydrospiro[benzo[1,2-b:5,4-b′]difuran-3,3′-indol]-1′(2′H)-yl)methyl]phenoxy}acetamide was obtained (81%) as a colorless solid的产率得到2-{4-[(2'-oxo-5,6-dihydrospiro[benzo[1,2-b:5,4-b']difuran-3,3'-indol]-1'(2'H)-yl)methyl]phenoxy}acetamide