Physicochemical properties and biological activity: Thermodynamic properties of compounds related to acetylcholine assessed from depression of freezing-point and enthalpies of dilution

1 Measurements have been made of the osmotic coefficients and enthalpies of dilution of acetylcholine and of compounds related to it in which the carbonyl and ether groups have been replaced by methylene and the trimethylammonium group by triethylammonium. All were iodides. Measurements were also made with tetraethylammonium iodide and agree with published values.