Platinum amine ligands

A versatile synthesis of monoamine platinum(II) complexes of the type ptCl3(amine)], where the nature of the amine ligand can be varied readily, involves treatment of the iodo-bridged dimer [PtI(/r-I)L]2 (L = NH3, methylamine, ethylamine, isopropylamine, cyclobutylamine, and... 

A wide range of multidentate amine ligands coordinate to platinum. The conformational analysis of chelate ring systems by NMR has been reviewed by Hawkins, and platinum complexes are included in this work.959 Amine ligands with sulfur groups can also act as chelates, and this subject has also been reviewed.960... 

In general terms, both steric effects and electronic factors are expected to play a role in determinating the reactivity of square-planar platinum complexes. The presence of planar amine ligands in cis- or /ran.y-Pt(anion )2 complexes and their orientation with respect to the coordination plane, as well as their substituents, can reduce the rates of DNA binding or thio binding compared to aliphatic ammine and amine complexes. Especially, substituents close to the coordination site should be expected to slow down axial substitution reactions at Pt. As there is now little doubt that DNA platina-tion is a key event (or THE key event) in the mechanism of action of platinum anticancer drugs, attention to the process of formation of the major adduct (GG) as an intrastrand cross-link between N(7) atoms of two adjacent guanine (G) residues, will remain important. 

Recent studies have shown that coordinated ammonia and amine ligands under basic conditions may effect nucleophilic attack at carbonyl centres in organic compounds, " These reactions occur due to formation of deprotonated amido species which can act as nucleophiles. For example, reaction of cobalt(III) and platinum(IV)ammines with ketones gives the corresponding Co and Pt imine complexes. A similar reaction between [Ru(NH3)6] and diones produces the corresponding Ru diimine (108). It has also been found that nitrilepentaammineruthenium(II)... 

Swiss pharmaceutical company Roche. It is a new platinum anticancer drug, result of a trinuclear platinum coordination complex with chloride and amine ligands. It is active through covalent adducts with DNA inducing apoptosis. 

Amine Ligands Are Not Lost From Platinum Upon Binding to DNA... 

A normal platinum azide is not known, but complex azides of both Pt(II) and Pt(IV) have been described. When investigating the latter, Curtius and Rissom [62] obtained red solutions of the potassium salt which exploded violently when heated, and a dark red residue, obtained upon concentration, exploded spontaneously with high brisance. The sensitivity disappears in combination with large organic cations or amine ligands, yielding compounds that decompose slowly when heated but are stable to impact. They are, however, photosensitive and will deteriorate within hours or days. 

The most important reaction of platinum(II) alkene complexes is nucleophilic attack at a coordinated carbon atom. The most studied nucleophile in this context is the amine nitrogen. Amines attack coordinated monoalkenes, and if tertiary phosphine or amine ligands are present these stabilize the Zwitterionic platinum-carbon a-bonded complexes that are formed (equation 239) The attack occurs trans to platinum. Substituents adjacent to the... 

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