6-methoxy-5-methylspiro[1-benzofuran-3,3'-indol]-2'(1'H)-one 、
乙腈 以
甲基叔丁基醚 为溶剂,
以(R)-6-methoxy-5-methyl-2H-spiro[benzofuran-3,3′-indolin]-2′-one was isolated as a crystalline colorless solid (0.81 g, 75% recovery)的产率得到(3R)-6-methoxy-5-methylspiro[1-benzofuran-3,3'-indol]-2'(1'H)-one