“…Pyridazines are important biologically active scaffolds, possessing antihypertensive 4 , cardiotonic 5 , analgesic 6 , anti-inflammatory 7 , antidepressant 8 , antibacterial 9 , anticancer 10 , nephrotopic drugs 11 , antithrombic 12 , diuretic 13 and anti-HIV 14 activities. Some pyridazine derivatives, such as bemoradan 15 , indolidan 16 , levosimendan 17 , pimobendan 18 , zardaverine 19 and imazodan 20 , have already appeared in the clinical market. Nitrogen containing heterocycles play an important role not only for life science industry but also in many other industrial fields related to special and fine chemistry.…”