Comprehensive Vibrational Spectroscopic Investigationof transtranstrans-Pt(N3)2(OH)2(py)2 a Pt(IV) Diazido Anticancer ProdrugCandidate

摘要

We report a detailed study of a promising photoactivatable metal-based anticancer prodrug candidate, trans,trans,trans-[Pt(N3)2(OH)2(py)2] (>C1; py = pyridine), using vibrational spectroscopic techniques. Attenuated total reflection Fourier transform infrared (ATR-FTIR), Raman, and synchrotron radiation far-IR (SR-FIR) spectroscopies were applied to obtain highly resolved ligand and Pt-ligand vibrations for >C1 and its precursors (trans-[Pt(N3)2(py)2] (>C2) and trans-[PtCl2(py)2] (>C3)). Distinct IR- and Raman-active vibrational modes were assigned with the aid of density functional theory calculations, and trends in the frequency shifts as a function of changing Pt coordination environment were determined and detailed for the first time. The data provide the ligand and Pt-ligand (azide, hydroxide, pyridine) vibrational signatures for >C1 in the mid- and far-IR region, which will provide a basis for the better understanding of the interaction of >C1 with biomolecules.