Synthesis and study of biological activity of some new 1,4-benzothiazines

N-(4-methylpyrimidin-2-one-4-yl)-1,4-benzothiazine-2,3-dione 5, 2-thio-2,6-dimethyl[1,3,5]triazino[3,4-c]-1,4-benzo-thiazine 9, [1,2,4]-triazino-2-oxo-[3,4-c][1,4]-benzothiazine 13, 5-arylidene-1H-1,4-benzothiazine[l,3,4]triazole 1,6a-b, 2-thio-6-methyl[1,3,5]triazino[3,4-c]benzothiazine 19, N-(2-propanoyl)-1,4-benzothiazne-3(1H)-one 20, tricyclic compound cyclopenteno-1,4-benzothiazine 21 have been synthesized and characterized by spectral data.