Mechanistic aspects of ligand substitution on cis-diaqua(cis-1,2-diaminocyclohexane)platinum(II) by Glycine-l-Leucine

Visual detection of a nerve agent simulant using chemically modified paper strips and dye-assembled inorganic nanocomposite

Chromogenic probe with oxidized bis-indolyl scaffold has been synthesized for the detection of a nerve gas mimicking agent, DCNP (diethyl cyanophosphonate) at pH 8.0 in water. The mechanism of interaction was proposed as the release of cyanide ion through the indole group mediating the hydrolysis of phosphorous-hetero atom bond and, thereafter, the Michael addition of the liberated CN^- ion to the electron deficient C[double bond, length as m-dash]C bond of the bis-indolyl moiety. The reaction featured a remarkable change in color from red to colorless at ambient condition. Then, low-cost and portable paper strips were designed for a rapid and on-site vapor phase detection of DCNP without involving any sophisticated instrument or skilled personnel. Finally, a dye assembled inorganic nanocomposite material was devised to achieve a more sensitive 'turn-on' detection of DCNP in water.

VP, Mitra I, Saha R, K. JCB, Reddy Dodda S, Linert W, Moi SC. In vitro model reaction of sulfur containing bio-relevant ligands with Pt(ii) complex: kinetics, mechanism, bioactivity and computational studies

In vitrodrug reservoir model reactions of thiols with novel Pt(ii) complex were investigated in aqueous medium and the complex and its substituted products show remarkable anticancer property.

Kinetic and Mechanistic Aspects of Ligand Substitution on cis- Diaqua (cis-1,2-Diaminocyclohexane)Platinum(II) with Three Glycine-Containing Dipeptides

The kinetics of the interaction of glycyl-L-valine(L1-L′H), glycyl-L-isoleucine (L2-L′H) and glycyl-L-glutamine(L3-L′H) with cis-[Pt( cis-dach)(OH2)2]2+ (dach = 1,2-diaminocyclohexane) have been studied spectrophotometrically as a function of [ cis-[Pt( cis-dach)(OH2)2]2+], [ligand], pH and temperature at constant ionic strength, where the complex exists predominantly as the diaqua species and the dipeptides as a zwitterion. The substitution reactions show two consecutive steps: the initial is the ligand-assisted anation and the subsequent step is chelation. The activation parameters for both steps were evaluated using Eyring's equation. The low DL H1 ≠ and large negative value of Δ S1 ≠ as well as Δ H2 ≠ and Δ S2 ≠ indicate an associative mode of activation for both the aqua ligand substitution processes. The products of the reactions have been characterised using IR and ESI-mass spectroscopic analysis. The title complex is already established as an anticancer drug; but its reactivity with all biomolecules will confirm its therapeutic activity (i.e. its efficacy versus toxicity).

Ligand substitution reaction on a platinum(ii) complex with bio-relevant thiols: kinetics, mechanism and bioactivity in aqueous medium

Kinetics of the interaction between [Pt(pic)(H₂O)₂](ClO₄)₂and selected thiols has been studied in aqueous medium as a function of [complex], [thiol], pH and temperature at constant ionic strength.