Study of phase equilibria and the physicochemical properties of selected pharmaceuticals

Crystal structure determination and thermal behavior upon melting of p -synephrine

“…This value differs from that reported in Ref. [7] (99.7 kJ mol −1 ) probably due to the fact that the experimental conditions are not identical. In our case, the DSC pans were perforated while, in the other case, the DSC experiments were conducted in hermetic pans.…”

“…But no indication is given on the measurement technique of the melting point and no enthalpy value has been determined. More recently, a DSC study carried out at 10 • C min −1 reports that synephrine melts at 190.53 • C with a 99.7 kJ mol −1 associated enthalpy [7]. However, the authors suspect that the product degrades upon melting in these experimental conditions.…”

Physicochemical Properties and Solubility of Hydrochloride Mucolytic Agents

“…Each experiment was performed at least in duplicate. Experimental points have been described by thermodynamic equations based on the theory of local concentrations: Wilson, NRTL, UNIQUAC [8][9][10]. The experimental data are presented in Table 1S, Table 3 and in Figs.…”

“…They were used to determine deviations from ideal solubility in comparison with the experimentally determined points. The equations used are presented in published papers [9,10]. The local concentration theory based models were chosen due to its applicability to a wide variety of APIs.…”

“…The models have been used to determine the solubility of e.g. flurbiprofen [8], octopamine HCl [9], synephrine [10], lobeline HCl [12], methyl xanthines [13], protein kinase CK2 inhibitors [14] or derivatives of anthranilic acid [15]. According to local concentration theory, the average concentrations of the substances described at the molecular level are differentiated.…”