Synthesis and Pharmacological Study of New 3,4-Dihydro-2H,6H-pyrimido( 2,1-b) (1,3)thiazines.

Summary A series of racemic pyrimido-thiazine derivatives was synthesized and many of their in vivo activities found to be comparable to acetylsalicylic acid and aminophenazone in an antiinflammatory model and an antipyretic test. Analogues 7a and 7e are the most potent in rat carrageenin and yeast fever assays. These compounds did not inhibit prostaglandin biosynthesis in vitro.