Volumes of some ionophorous antibiotics (monensin, grisorixin and nigericin) according to their state in solution. Acid forms, anion and sodium and potassium salts

Abstract

Apparent molal volumes of the various forms of some ionophorous antibiotics in methanol have been obtained from density measurements. The discussion focuses on the shape and contraction of the various species according to their size and the number of hydroxylic groups which can participate through hydrogen bonding in the formation of the structure. More simple hydroxycarboxylic acids have also been studied to compare the effect of the chelation of these acids and the antibiotics on both the volume and dissociation constant.