MIXED-LIGAND COMPLEXES OF CIS-DICHLOROETHIONINEPLATINUM(II) AND CIS-DICHLOROETHIONINEPALLADIUM(II) WITH SUBSTITUTED PYRIMIDINES

Mixed ligand complexes of cis-dichloroethionineplatinum (II) and cis-d ichloroethioninepalladium (II) with pyrimidines, viz 2-hydroxypyrimidi ne, hydrochloride, isocytosine, 2-mercaptopyrimidine, 5-amino-uracil, 2-thiocytosine, and 2-thiouracil have been synthesised and characteris ed by elemental analysis, conductivity data, IR, UV, H-1 and C-13 NMR spectra. Based on the spectral data it is found that ethionine coordin ates to the metal ion through sulphur and amino nitrogen, leaving a fr ee carboxylic acid group. 2-Hydroxypyrimidine hydrochloride, isocytosi ne, 2-mercapropyrimidine act as monodentate ligands and bind to Pt(II) and Pd(II) through N-3, while 5-aminouracil coordinates to the metal ion through the amino (NH2) group. The 2-thiocytosine and 2-thiouracil however act as bidentate ligands. coordinating to the metal ion throu gh ring nitrogen (N-3) and sulphur.