Dimethyl Sulfoxide Containing Platinum(II) and Palladium(II) Chelate Complexes of Glyoxylic and Pyruvic Acid Thiosemicarbazones. A New Class of Cytotoxic Metal Complexes

Abstract

The complex [Cu(en) 2 (H 2 O)](sy) 2 (en)(H 2 O) 2 has been synthesized and characterized by its electronic and vibrational spectra. The molecular structure of the complex has been determined by X-ray diffraction methods. The complex crystallizes in the orthorhombic space group Pnma with unit-cell parameters a = 10.7236 (5), b = 20.4660(10), c = 14.4523(11)Å and Z = 4. In the cation, the Cu(II) ion has a distorted square pyramidal coordination with two bidendate (en) ligands forming the basal plane and a H 2 O molecule in the apical position. The complex cations and syringate anions constitute chains along the b axis in -A-B-A-fashion. The members of the chains are linked by through N-H···O hydrogen bonds. The (en) molecules are responsible for connecting adjacent layers.

Structure of (dimethyl sulfoxide‐S){glyoxylic acid thiosemicarbazonato(2–)‐O,N,S }platinum(II)

“…Finally, in the case of 1 this was confirmed by single crystal X-ray diffraction [1]. Nevertheless, after careful examination of a crystal specimen of 1, a very small number of plate-shaped crystals (1a) were noticed in the mass of block-shaped crystals reported previously [1], and they were studied by X-ray crystallography. The results of this study, which we report here, revealed that the crystal form 1a does not contain DMSO of solvation.…”

“…The synthesis of 1 and the preparation of a crystalline sample for X-ray diffraction have been described in detail previously [1]. A plate-shaped crystal of 1a for the present study was selected from the same crystalline sample.…”

“…Quite recently [1] we described the synthesis, spectroscopic characterization and cytostatic effect of the complexes [Pt(DMSO)(GT)]·DMSO (1), [Pt(DMSO)(PT)] · ½DMSO (2) and [Pd(DMSO)(PT)] (3), where DMSO = dimethyl sulfoxide, H 2 GT = glyoxylic acid thiosemicarbazone and H 2 PT = pyruvic acid thiosemicarbazone ( Fig. 1), and the structure of complex 1 was confirmed by X-ray crystallography.…”

“…1), and the structure of complex 1 was confirmed by X-ray crystallography. The reasons to design this novel class of cytotoxic metal complexes were stated in detail elsewhere [1], along with a comprehensive literature survey. The complexes mentioned represent a peculiar expansion of the class of Pt(II) and Pd(II) chelates containing tridentate coordinated heterocyclic thiosemicarbazones, whose coordination chemistry and cytostatic activity has been studied by us [2][3][4][5][6][7][8] since a decade.…”

Synthesis of platinum complexes with 2-(5-perfluoroalkyl-1,2,4-oxadiazol-3yl)-pyridine and 2-(3-perfluoroalkyl-1-methyl-1,2,4-triazole-5yl)-pyridine ligands and their in vitro antitumor activity

“…The coordination mode of the complexes in solution was determined by using the 1 H NMR spectra and the assignments of resonances were based on literature data [40,9] and are in good agreement with proposed structure. The numbering of protons used for 1 H NMR is shown in Scheme 2.…”