The oxidation stability of base stocks in the presence of some synthesized Benzothiazoles derivatives, 2-
(benzothiazol-2-ylthio)-N-butylacetamide (Ia), 2-(benzo-thiazol-2-ylthio)-N-octyl-acetamide (Ib) and 2-
(benzothiazol-2-ylthio)-N-dodecylaceta-mide(Ic), as oxidation inhibitors has been studied. The structures of these
prepared compounds are elucidated by the common tools of analysis, Elemental analysis, I.R. and 1H-NMR
spectroscopy. The oxidation reaction of these compounds with one of the base stocks that used in the formulation
of the local lubricating oil was investigated, using the change in Total Acid Number (TAN), Viscosity, and InfraRed (IR) spectroscopy. The data obtained, reveals that these prepared compounds gave good results. The
efficiency order is shown as follows Ib and Ic > Ia.