Multinuclear NMR spectroscopy and antiproliferative activity in vitro of platinum(II) and palladium(II) complexes with 6-mercaptopurine

• Published in: Journal of molecular structure 2004-11, Vol.707 (1), p.241-247
• Main Authors: Łakomska, Iwona, Pazderski, Leszek, Sitkowski, Jerzy, Kozerski, Lech, Pełczyńska, Marzena, Nasulewicz, Anna, Opolski, Adam, Szłyk, Edward
• Format: Article
• Language: English
• Subjects: 6-mercaptopurine; Antiproliferative activity in vitro; Multinuclear NMR; Palladium complex; Platinum complex
• ISSN: 0022-2860; 1872-8014
• DOI: 10.1016/j.molstruc.2004.07.027

A series of Pd(II) and Pt(II) complexes with 6-mercaptopurine (6-Hmp) of formulae Pd(6-Hmp) 2Cl 2 ( 1), Pd(6-mp) 2·2H 2O ( 2), Pt(6-mp) 2·2H 2O ( 3), Pt(6-mp)(dmso)Cl ( 4) was synthesized and studied by IR, far-IR, 1H, 13C, 15N NMR. ( 1) has an ionic character and consists of distinct [Pd(6-Hmp) 2] 2+ cations and uncoordinated Cl − anions, whereas ( 2,3) are neutral species with central atoms bis-chelated by the deprotonated 6-mp − ligands. NMR studies suggest that S and N(7) are the complexation sites, while far-IR spectra indicate the square-planar geometry of Pd(II) or Pt(II). In ( 4) the Pt(II) atom is coordinated by one chelating 6-mp − anion, S-bonded dmso molecule and a terminal chloride. The antiproliferative activity in vitro of ( 2–4) was tested against human leukaemia HL-60 cells, being exhibited for ( 2) at the level ca. six times lower than in case of cisplatin.