4'-chloro-5,6-dihydrospiro[benzo[1,2-b:5,4-b']difuran-3,3'-indol]-2'(1'H)-one 、 5,6-dihydrospiro[benzo[1,2-b:5,4-b']difuran-3,3'-indol]-2'(1'H)-one 、
(R)-(tetrahydrofuran-2-yl)methyl 4-methylbenzenesulfonate 、
2-(bromomethyl)tetrahydro-2H-pyran 以4′-chloro-1′-[(2R)-tetrahydrofuran-2-ylmethyl]-5,6-dihydrospiro[benzo[1,2-b:5,4-b′]difuran-3,3′-indol]-2′(1′H)-one was obtained (80%) as a colorless solid的产率得到4'-chloro-1'-[(2R)-tetrahydrofuran-2-ylmethyl]-5,6-dihydrospiro[benzo[1,2-b:5,4-b']difuran-3,3'-indol]-2'(1'H)-one