Scheme 1From: Synthesis and evaluation of substituted diphenyl-1,3,4-oxadiazole derivatives for central nervous system depressant activity(a) Conc. H2SO4, Ethanol, Reflux 4hr; (b) Hydrazine Hydrate, Ethanol, Reflux 8 hr; (c) Substituted benzoic acid (R=p-OH, p-NH2, p-Cl, p-NO2, o-Br), Phosphorous Oxychloride, Reflux 2-3 hr.Back to article page