Synthesis, Characterization and Antitumour Activity of 5-Chlorouracil and 5-Chlorouracil-Histidine Complexes with Some Metal(III) Ions

Abstract

Complexes of the type [AIL(OH)CI], [ML(OH)₂] and [M′LL′(H₂O)CI], where HL = 5-chlorouracil; HL′ = histidine; M = Cr(III) or Fe(III) and M′ = Al(III), Cr(III) or Fe(III), were synthesized and characterized. The complexes are polymeric in nature showing high decomposition points and are insoiuble in water and common organic solvents. 5-Chlorouracil is coordinated to the metal ion through the O atom of C₍₄₎[dbnd]O and the N atoni of N₍₁₎ while histidine through the O atom of -COO⁻ and the N atom of -NH₂ group. The μ_eff values, electronic spectral bands and ESR spectra suggest a polymeric 6-coordinate spin-free octahedral stereochemistry for the Cr(III) and Fe(III) complexes. In vivo and in vitro antitumour activity results indicate that the Cr(III) complexes have significant activity against P815 murine mastocytoma but the Al(III) complexes show poor activity.