Investigation on the interaction between theophylline and alkaline substances using the DAOSD approach

The interaction between theophylline and ethylenediamine , choline hydroxide and other alkaline compounds was investigated via UV–Vis spectroscopic method . Upon introduction of alkaline compounds, the π-π transition band of theophylline undergoes a red shift. This phenomenon is a result of removing a proton from the 7-position of a theophylline molecule. Moreover, cross peaks appear in 2D asynchronous spectra generated via the DAOSD approach on theophyllinate and various cation systems. These results suggest that cation-π interaction and cation-anion interactions occur between theophyllinate and various cations including ethylenediamine , choline , tetramethyl ammonium , K + and Cs + . The interaction between anionic theophyllinate and various cation may play a considerable role in the transmembrane transport of theophylline in medicinal process.