Alzheimer's disease is the most common form of dementia in persons over the age of 65, and its etiology is linked to oxidative stress. In this work, an easy and efficient access to two new hydrazones Schiff bases as (2-Cl MHB and 2-Cl BHB). These compounds were prepared by condensation of 2-Chloro phenyl hydrazine with benzil.The structure of each of the two compounds was determined by the X-ray diffraction technique performed on single crystals. In a second part, an attempt to evaluate the biological properties is carried out on the two hydrazones such as the antioxidant power (by two methods: DPPH and CUPRAC) and the anti-cholinesterase activity (AChE, BChE) against the disease of Alzheimer's. The results obtained must be taken into account with other studies to improve their inhibitory activity.