Applied chemical thermodynamics and kinetics on pharmaceutical compounds

Abstract

The important role of thermoanalytical methods in the field of pharmaceutical and galenic research is outlined. The thermodynamic stability of polymorphic forms of a substance is discussed.The development of a pharmaceutical compound or a dosage form is a long-range task affording normally a period of more than ten years. Many research and development steps are necessary from the first step the synthesis of a pharmaceutical compound for which a certain therapeutic effect can be expected to the final step of the galenic formulation.A second development pathway gains to-day a marked importance in creating new dosage forms for already known pharmaceutical compounds. The whole field of the galenic development changed in the last years to a major research and development task. Of course the question may be put foreward what are the rational facts causing such a shift of emphasis. First of all many John Wiley & Sons, Limited, Chichester Akaddmiai Kiad6, Budapest

Influence of Aliphatic Chain Length on Structural, Thermal and Electrochemical Properties of n-alkylene Benzyl Alcohols: A Study of the Odd–Even Effect

“…Considering the lattice energy calculations, it is interesting to note that the energies calculated by Pixel and CrystalExplorer correlate quite well, with the largest difference calculated for Do5OH. Similar results with other computational methods and different physical characteristics were previously reported [31]. Unfortunately, the crystal structures of the n = 1 and 3 chain analogs were determined without hydrogen atoms, and the structure of the chain analog n = 2 is disordered; therefore, a detailed analysis of intermolecular interactions was not conducted.…”

“…The calculated melting entropies for I and II are 0.053 kJ mol −1 K −1 and 0.081 kJ mol −1 K −1 , respectively. The Gibbs free energy diagram (Figure S7) was constructed over the temperature range of 100 K-400 K. The results indicate that two Gibbs free energy curves intersect at approximately 150 K. The heat of fusion rule, entropy of fusion rule [30] and Gibbs energy diagram indicate the enantiotropic relationship between two polymorphs [31][32][33].…”