Synthesis, antihistaminic and cytotoxic activity of pyridothieno- and pyridodithienotriazines

Article abstract of DOI:10.1016/S0223-5234(99)80013-0

The synthesis of pyrido[3',2':4,5]thieno[3,2-d]-1,2,3-triazines 7a-n and 8a-c and pyrido[3',2':4,5]dithieno[3,2-d]-1,2,3-triazines 15 and 16a-c, and their inhibitory action on the release of histamine from rat mast cells under immunological and chemical stimulus are presented. Compounds 7b and 16a are strong inhibitors under all the conditions tested while 16c is a good inhibitor in all conditions except when it is preincubated with ovoalbumin. Compounds 7k, 7m and 7n are good inhibitors in the immunological experiments but are practically inactive under chemical stimulus. Compounds 6a and 15 show in vitro cytotoxic activity against several human and mouse tumoral cell lines with IC₅₀ values well under 1 mg/mL.