The author of 《Influence of pH on the action of parasmypathomimetic drugs》 were Luellmann, Heinz; Peters, Thies. And the article was published in European Journal of Pharmacology in 1967. Product Details of 1690-72-8 The author mentioned the following in the article:
The influence of pH on the activity of parasympathomimetics with a tertiary N was investigated using guinea pig isolated atria and ileum segments. Carbachol and arecaidine ester methiodide, both quaternary cholinomimetics, were used as reference compounds The responses of the organs were unchanged within the pH ranges 6.2-8.4 (ileum) and 6.3-8.8 (atria). The pK values of the tertiary parasympathomimetics investigated also lay within these ranges. The tertiary parasympathomimetics had agonist activity only in the protonated form. The slope of the concentration-response curves was reduced for both tertiary and quaternary parasympathomimetics as the OH- concentration was increased. In contrast to the behavior of the quaternary compounds, the intrinsic activity of the tertiary parasympathomimetics increased when OH- concentration was raised. The intrinsic activity of the tertiary compounds may be even higher than that of the quaternary compounds The pH of the medium not only determined the degree of protonation of the tertiary agonists, but also influenced the slope of the concentration-response curves and the intrinsic activity. In the experimental materials used by the author, we found Methyl 1-methylpiperidine-3-carboxylate(cas: 1690-72-8Product Details of 1690-72-8)
Methyl 1-methylpiperidine-3-carboxylate(cas: 1690-72-8) is a member of piperidine. Piperidine is ubiquitous structural motif widely occurred in diverse synthetically and naturally occurring bioactive molecules. Piperidines are an immensely important class of compounds medicinally: the piperidine ring is the most common heterocyclic subunit among FDA approved drugs.Product Details of 1690-72-8
Referemce:
Piperidine – Wikipedia,
Piperidine | C5H11N – PubChem