N-[4-[2-(3,4-dihydroxyphenyl)ethyl]phenyl]-3,4-dihydro-4-oxo-2H-1-benzothiopyran-3-carboxamide, 1,1-dioxide 在
sodium hydroxide 、
乙酸酐 作用下,
以10.4 g (45%)的产率得到N-[4-[2-[3,4-Bis(acetyloxy)phenyl]ethyl]phenyl]-4-hydroxy-2H-1-benzothiopyran-3-carboxamide, 1,1-dioxide