To assess the chemical stability of new QASs, additional 1 H and 13 C NMR spectra of 2 exemplary salts: 1Asp and 1Ala were acquired 5 and 7 months following their synthesis, respectively. From the comparison of the obtained spectra (Fig. can be observed that the same signals originating from cations and anions of QASs are present in the spectra obtained both immediately after synthesis and after long-term storage. This result implies that the new QASs can be stored in pure form for at least 5 months without the appearance of any decomposition products in noticeable amounts.