Synthesis and antihypertensive evaluation of some phthalazines containing 1,3,4-thiadiazines and 1,3,4-thiadiazin-5-ones

Starting from methyl N2[4-methylphthalazin-1-yl]dithiocarbazinate, a number of new phthalazine derivatives containing 1, 3, 4-thiadiazine and 1, 3, 4-thiadiazin-5-one rings were prepared. The structure of the new products was confirmed by spectral analysis besides synthesis via other routes. A preliminary antihypertensive evaluation revealed that most compounds possess moderate antihypertensive activity