prenyl coumarin on oxidation with m chloroperbenzoic acid in chloroform solvent gave dihydroxanthyletin tetrahedron 27 1247 1971 tetrahedron 27 4901 1971 the synthetic seselin was prepared starting from 7 hydroxy coumarin umbelliferone condensation of 7 hydroxy coumarin with 2 chloro 2 methyl but 3 yne in the presence of base gave propargylether the propargylether on heating at 200 u00b0 c with n n dimethyl aniline gave seselin tetrahedron 27 1247 1971 tetrahedron 27 4901 1971 experimental procedures for in vitro and in vivo evaluation of u00b1 marmesin columbianetin dihydroxanthyletin seselin and coumarin derivatives single trial passive avoidance is widely used as experimental test to assess learning memory functions in rodents scopolamine induced impairment in passive avoidance in vivo and inhibition of acetylcholinesterase in vitro in rodents are commonly employed and screening test to predict potential of an acetylcholinesterase inhibitor as cognitive enhancer anti dementic drug the study was conducted in adult swiss male mice of 3 4 months wt 20 25 g were kept in standard housing condition with 12 h light and dark cycle the food and water were available ad libitum the mice were subjected to single trial passive avoidance test as described by brioni the passive avoidance test was studied by a computerized shuttle box columbus instruments ohio usa provided with a software program pacs 30 the shuttle box is comprised of two compartments an automated door was used to isolate the compartments after an exploration period of 30 s for acclimatization the animal was subjected.