2-氨基-4,7-二氢-5H-噻吩并[2,3-c]硫代吡喃-3-羧酸乙酯 以
乙酸乙酯 为溶剂,
以the title compound (2.23 g, yield 84%) was obtained by an operation similar to that of Reference Example 45 and trituration with ethyl acetate的产率得到2-amino-4H,5H,7H-thieno[2,3-c]thiopyran-3-carboxylic acid