Synthesis, cytotoxicity, antibacterial activity and molecular modeling study of new mono , homo and heterobimetallic complexes of palladium (II) with some transition metal ions containing the ligands N-phenyl-N'-(2-thiazolyl)thiourea and Diphosphines Ph2P(CH2)nPPh2( where n = 1- 3)

Abstract

The ligand N-phenyl-N'-(2-thiazolyl) thiourea (LH) was prepared from reaction of phenyl isothiocyanate with 2-aminothiazol. Treatment of deporotonated ligand (LH) with sodium tetrachloro palladate(II) afforded [Pd(L)₂] complex 3. Reaction of complex 3 with [bis(diphenylphosphino) methane, dppm], [1,2-bis(diphenylphosphino)ethane, dppe] and [1,3-bis(diphenylphosphino)propane, dppp] afforded the mixed ligand complexes of the type [Pd(II)L₂(Ph₂P(CH₂)_nPPh₂)], {where n = 1, dppm], n = 2, dppe or n = 3, dppp) 4-6, respectively.  Further, complexes 4-6 were treated with some transition metal salts to give homo- and heterobimetallic complexes 7-21 of the types: [(Ph₂P(CH₂)_nPPh₂) Pd (II)-µ-L₂M'(II)X_m] and [(Ph₂P(CH₂)_nPPh₂)Pd(II)-µ-L₂M'(II)X_m xH₂O] ( where  n= 1, 2, or 3 , M' = Pd(II), Ni(II), Mn(II), Co (II) or Cu (II) and X = Cl^-, m = 2). The ligand and the prepared complexes were characterized by elemental analysis, molar conductivity, magnetic susceptibility, FTIR, UV-Vis, ¹H-³¹P{¹H} NMR and mass spectroscopy. Some of these complexes were assayed for their inhibition activity against human rhabdomyosarcoma cell line (RMS). Interestingly, compound 19 exhibited a significant cytotoxicity inhibition activity ~ 90% for RMS cell line, suggesting being a new lead in the development of human muscle anticancer agent. All the compounds have been screened for their antibacterial activity against S. aureus and E. coli bacterium.