Mixed ligand complex via zinc(II)-mediated in situ oxidative heterocyclization of hydrochloride salt of 2-chlorobenzaldehyde hydralazine hydrazone as potential of antihypertensive agent.

An unusual tetrahedral mixed ligand Zn(II) complex ZnT(L)Cl, where L = 2-chlorobenzaldehyde hydralazine hydrazone and T = in situ generated 3-(2-chlorophenyl)-1,2,4-triazolo[3,4-a]phthalazine is reported. Structure of the fused triazole has been confirmed by single crystal X-ray diffraction studies. Structure of Co(II), Ni(II), Cu(II) and Zn(II) complexes has been confirmed by spectral and analytical methods. Metal complexes have exhibited better activity in the fructose induced hypertension studies in animal model and are comparable with the standard.