eduzhai > Life Sciences > Biochemistry >

Binuclear platinum (II) complexes with benzodiazine as bridging ligands promote the hydrolysis of methionine and histidine containing peptides: the effect of ligand structure on the catalytic ability of platinum (II) complexes

  • sky
  • (0) Download
  • 20211118
  • Save

... pages left unread,continue reading

Document pages: 12 pages

Abstract: Binuclear platinum complexes [{Pt (EN) cl}2 (- QX)] Cl2 · 2H2O (1), [{Pt (EN) cl}2 (- QZ)] (ClO4) 2 (2) and [{Pt (EN) cl}2 (- phtz)] Cl2 · 4H2O (3) were synthesized and characterized by different spectral techniques. The crystal structure of 1 was determined by single crystal X-ray diffraction analysis, and DFT m06-2x method was used to optimize the structure of 1 – 3. Platinum (II) chloride complexes 1-3 were transformed into corresponding aqueous species 1a-3a, and their reaction with equimolar amounts of AC – L – met – Gly and AC – L – his – Gly dipeptides was studied by 1H NMR spectroscopy in the pH range of 2.0 < < pH < < 2.5 at 37 ° C. It was found that in all the studied reactions with AC – L – met – Gly dipeptide, the met – Gly amide bond had been broken, but complexes 2a and 3aed lower catalytic activity than 1a. However, in the reactions with Ac–L–His–Gly dipeptide, the hydrolysis of the amide bond involving the carboxylic group of histidine was observed only with complex 1a. The observed disparity in the catalytic activity of these complexes is thought to be due to different relative positioning of nitrogen atoms in the bridging qx, qz, and phtz ligands and consequent variation in the intramolecular separation of the two platinum(II) metal centers.

Please select stars to rate!

         

0 comments Sign in to leave a comment.

    Data loading, please wait...
×