Solubility of Thiophene-, Furan- and Pyrrole-2-Carboxaldehyde Phenylhydrazone Derivatives in 2.82 mol⋅L−1 Aqueous DMSO at 298.15 K, Inhibition of Lymphoproliferation and Tubulin Polymerization: A Study Based on the Scaled Particle Theory

In this work, the solubilities of nine phenylhydrazone derivatives in water and in 2.82 mol?L^?1 aqueous DMSO at 298.15 K, expressed on the molar fraction scale, are reported. The estimated value of the standard Gibbs energy for transferring the solute from water to 2.82 mol?L^?1 DMSO, $\Delta G^{0}_{\mathrm{W}\rightarrow \mathrm{mix}}$ , for each system, indicates that it is a spontaneous process. Some of the phenylhydrazone derivatives inhibited the induction of T lymphocyte proliferation by phytohaemagglutinin (PHA) but only DPCT and NPCF efficiently inhibited Guinea pig brain tubulin polymerization. Scaled Particle Theory (SPT) was used to interpretate solubility and biological activity results. Based on the results we suggested that the difference in the work of cavity creation ΔΔG _c, associated with the transfer of the phenylhydrazone derivatives from water to 2.82 mol?L^?1 aqueous DMSO, is the dominant factor in the magnitude of $\Delta G^{0}_{\mathrm{W}\rightarrow \mathrm{mix}}$ . The later quantity was considered to be an indirect measurement of the hydrophobic character of these derivatives, and it can be used to interpret the biological results.     

Influence of the dielectric medium on the carbonyl infrared absorption peak of acetylferrocene

The solvent effect on the position of the carbonyl vibrational stretching of acetylferrocene in aprotic media was studied in this work. The solvent-induced shifts in this organometallic compound were interpreted in terms of the alternative reaction field model(SCRF-MO) proposed by Kolling. In contrast to the established trends for carbonyl groups in organic systems, the results suggest that the continuum models for the reaction field are not adequate and that the influence of dipolarity-polarizability described by an inhomogeneous coupling function theta(epsilon )L(n(2)) that assumes optical dielectric saturation is responsible for the carbonyl band shift and, there is empirical evidence that the effect of field-induced intermolecular interaction on band shift, interpreted in terms of the van der Waals forces from the solvent, have a important contribution to this phenomena.