Designing Tailored Thiosemicarbazones with Bespoke Properties: The Styrene Moiety Imparts Potent Activity, Inhibits Heme Center Oxidation, and Results in a Novel "Stealth Zinc(II) Complex?

Dharmasivam M., KAYA B., Wijesinghe T., Azad M. G., Gonzalvez M. A., Hussaini M., ...More

JOURNAL OF MEDICINAL CHEMISTRY, vol.66, no.2, pp.1426-1453, 2023 (SCI-Expanded) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 66 Issue: 2
  • Publication Date: 2023
  • Doi Number: 10.1021/acs.jmedchem.2c01600
  • Journal Name: JOURNAL OF MEDICINAL CHEMISTRY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus, Academic Search Premier, BIOSIS, Biotechnology Research Abstracts, CAB Abstracts, Chemical Abstracts Core, Chimica, EMBASE, MEDLINE, Veterinary Science Database, Index Chemicus (IC)
  • Page Numbers: pp.1426-1453
  • Istanbul University Affiliated: No

Abstract

A novel, potent, and selective antitumor agent, 3-thiosemicarbazone (PPP44mT), and its analogues were synthesized and characterized and displayed strikingly distinctive properties. This activity was mediated by the inclusion of a styrene moiety, which through steric and electrochemical mechanisms prevented deleterious oxy-myoglobin or oxy-hemoglobin oxidation relative to other potent thiosemicarbazones, i.e., di-2-pyridylketone-4-cyclohexyl-4-methyl-3-thio semicarbaz one (DpC) or di-2-pyridylketone-4,4-dimethyl-3-thiosemicarbazone (Dp44mT). Structure-activity relationship analysis demonstrated specific tuning of PPP44mT electrochemistry further inhibited oxy-myoglobin or oxy-hemoglobin oxidation. Both PPP44mT and its Cu(II) complexes showed conspicuous almost immediate cytotoxicity against SK-N-MC tumor cells (within 3 h). In contrast, [Zn(PPP44mT)2] demonstrated a pronounced delay in activity, taking 48 h before marked antiproliferative efficacy was apparent. As such, [Zn(PPP44mT)2] was designated as a "stealth Zn(II) complex" that overcomes the near immediate cytotoxicity of PPP44mT or its copper complexes. Upon examination of the suppression of oncogenic signaling, [Zn(PPP44mT)2] was superior at inhibiting cyclin D1 expression compared to DpC or Dp44mT.