Platinum(ii) complex and processes for preparing the same

Abstract

Disclosed herein are novel platinum(II) complexes having a potent anti-tumor activity which are represented by the formula (1), ##STR1## wherein R.sub.1 and R.sub.2, which may be the same or different, are a hydrogen atom or a C.sub.1-4 alkyl group, respectively, or jointly form a cycloalkane group together with the carbon atom attached thereto; two Xs jointly form a group represented by formula (a) or (b) wherein, R.sub.3 is a hydrogen atom or a methyl group; R.sub.4 and R.sub.5, which may be the same or different, are a hydrogen atom or a C.sub.1-4 alkyl group, respectively, or jointly form a cyclobutane together with the carbon thereto; and the absolute configurations at the respective chiral centers in the 4,5-bis(aminomethyl)-1,3-dioxolane moiety are (4R,5R) or (4S,5S); processes for the preparing the same; and their use for treating animal or human cancer. Further, disclosed herein are novel intermediates useful for the preparation of the platinum(II) complexes and processes for preparing said intermediates.