1-methyl-1H-spiro[furo[3,2-g][1,4]benzoxazine-8,3'-indole]-2,2'(1'H,3H)-dione 、 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1-methyl-1′-[(2R)-tetrahydrofuran-2-ylmethyl]-1H-spiro[furo[3,2-g][1,4]benzoxazine-8,3′-indole]-2,2′(1′H,3H)-dione was obtained (69%) as an off-white solid的产率得到1-methyl-1'-[(2R)-tetrahydrofuran-2-ylmethyl]-1H-spiro[furo[3,2-g][1,4]benzoxazine-8,3'-indole]-2,2'(1'H,3H)-dione