magnesium(II) perchlorate 、
indoline-2-carboxylic acid n-propyl ester 、 1-[(2S,3R,4S)-3,4-dihydro-2-dimethoxymethyl-3-hydroxy-2-methyl-6-nitro-2H-1-benzopyran-4-yl]-(2R)-2,3-dihydro-1H-indole-2-carboxylic acid ethyl ester 以
乙腈 为溶剂,
以35%的产率得到1-[(2R,3S,4R)-3,4-dihydro-2-dimethoxymethyl-3-hydroxy-2-methyl-6-nitro-2H-1-benzopyran-4-yl]-(2S)-2,3-dihydro-1H-indole-2-carboxylic acid n-propyl ester