反应详情

A mixture of methyl 4-hydroxy-2-methyl-2H-1,2-benzothiazine-3-carboxylate 1,1-dioxide (2.95 g) and 2-amino-7-hydroxy-2,4,6-cycloheptatrien-1-one (1.5 g) in xylene (103 ml) was refluxed for 52 hours. The reaction mixture was cooled to room temperature. The crystals were collected by filtration and washed successively with N,N-dimethylformamide and chloroform to give 4-hydroxy-N-(7-hydroxy-1-oxo-2,4,6-cycloheptatrien-2-yl)-2-methyl-2H-1,2-benzothiazine-3-carboxamide 1,1-dioxide (3.7 g).

1. temperaturewas refluxed for 52 hours
2. filtrationThe crystals were collected by filtration
3. washwashed successively with N,N-dimethylformamide and chloroform