Synthesis and properties of novel platinum(IV) complexes involving asymmetric chiral diamines as carrier ligands

Abstract

Novel platinum(IV) complexes with asymmetric chiral diamine ligands cis,cis,trans-A(2)PtCl(2)(X)(2) (X = OH, OCOCH3, OCOC2H5, A(2) = NH2CH(CH3)CH2NH(c-C6H11)(apcha), NH2CH(CH3)CH2NH(c-C5H9)(apcpa)) have been prepared. One of the platinum(IV) complexes, ( apcpa)PtCl2(OCOC2H5)(2)(6), was subjected to X-ray crystallographic analysis. The crystal structure of (apcpa)PtCl2(OCOC2H5)(2) (monoclinic, P2(1) (No. 4), a = 9.1391(1), b = 22.2517(1), c = 10.0687(1) Angstrom, beta = 109.105(1)degrees, V = 1934.80(3) Angstrom(3), Z = 4, R-1 = 0.0532) exhibits that the platinum atom achieves a typical octahedral arrangement with two nitrogen atoms in cis positions and two carboxylato group in trnas positions. The spectroscopic data disclose that these platinum(IV) complexes are stable and their molecular structures are retained in aqueous solution. The title complexes are highly cytotoxic in vitro but do not exhibit oral anticancer activity in vivo.