Potentiometric Study of Hydroxamic Acids in Non- Aqueous Media

Hydroxamic acids have been recognized as compounds of pharmacological, toxicological and pathological importance. The hydroxamic acid functionality -NOH. C=O, is the outstanding chemical feature of these molecules and is responsible for their biological and medicinal properties. The distribution, transport behavior, bonding to receptors and contribution to metabolic behavior of the molecules depend on the protonation constants. However its value depends on the structure of the molecules. The protonation behavior of two hydroxamic acids was determined in methanol and dimethylsulfoxide using glass and platinum electrode and calomel as reference electrodes. Tertbutylammonium hydroxides were used as the titrant in non-aqueous medium. Based on these data, pKa values of hydroxamic acids are then computed.