New trends in platinum and palladium complexes as antineoplastic agents

The discovery of cisplatin (cis-Pt(NH3)2Cl2) as an antineoplastic agent has focused attention on the rational design of metal complexes that can be potentially used in cancer chemotherapy. Today, the pharmaceutical industry invests more than $1 billion each year in the development of new metal-based drugs to improve biological activities, in terms of cellular selectivity, therapeutic efficiency and minimization of side effects. Chemotherapies based on transition metals play a key role in cancer treatment, and among them platinum and palladium are the most fruitful. This article reviews the main recent advances in the design and synthesis of platinum- and palladium-based drugs, their structural features and biological studies of them. The rationale for the choice of the ligand, related to leaving groups, the geometry of the complex and the oxidation state of the metal ion, is discussed. An overview of the main biological techniques and approaches for testing the interaction of these molecules with the biological environment, mainly DNA, to validate the effect is also provided

Chelate ring sequence and enthalpy of formation of copper(II) complexes with tetraaza macrocycles

The heats of formation of the Cu2+ tetraaza macrocycle complexes I, m = n =p = 2, q = 3 (CuL2+); m = n = 2, p = q = 3 [CuL1]2+], and II [69238-28-4] were detd. calorimetrically at 25°. The heat of formation of CuL2+ is intermediate between those for analogous complexes with cyclam and 1,4,7,10-tetraazacyclotridecane. L1(isocyclam) incorporates Cu2+ less exothermically than cyclam due to weaker in-plane Cu-N interactions. II has a much lower heat of complexation

New fluorescent chemosensors for metal ions in solution

After a brief introduction on the main transduction mechanisms for metal ion detection by fluorescence, this paper reviews ligand molecules containing fluorophores synthesized and employed in metal ions sensing in solution in the last few years. With the aim of making more readable the paper we have organized it by dividing the subject first for type of fluorophore, then type of metal ion. Because of many acronyms a glossary has been inserted

Enthalpy of formation of copper(II) complexes with 14-membered tetraaza macrocycles

The heat of formation of complex I (n = 2, m = 3) exceeds that of I (n = 3, m = 2), which in turn exceeds that of the fused system II. These effects are caused by deformations in the macrocyclic framework, resulting in decreases in the in-plane Cu-N interactions

Thermochemistry of metal complexes with the rigid ligand 1,3,5-cis,cis-triaminocyclohexane

The heats of formation of 1:1 and 1:2 complexes of Ni2+ and Cu2+ with the ligand 1,3,5-cis,cis-triaminocyclohexane [26150-46-9] were detd. in aq. soln. by microcalorimetric methods. The corresponding entropy values were obtained by combination with literature free energy values. Comparison with data for the coordination of more flexible triamines emphasizes the role of the rigidity of the ligand

Continuous and Discontinuous Thermochromism of Copper(II) and Nickel(II) Complexes with N,N'-diethylethylene diamine

The ir spectra of trans-[ML2]X2 (M = Cu, Ni; L = Et2NCH2CH2NH2; X = BF4-, ClO4-, NO3-) are reversibly temp. sensitive. An increase of temp. causes a red shift in the visible absorption band of the Cu complexes, and the d-d absorption bands of the thermochromic Ni complexes also shift to lower frequencies with increasing temp. From differential scanning calorimetry (DSC) in the temp. range between -100° and the melting decompn. temp. (∼200°), these compds. which show a sharp spectral transformation also show an endothermic transition. The transition temp. measured by DSC is identical with that detd. spectroscopically. Thermogravimetric anal. shows that there is no wt. change on heating