Alzheimer's disease (AD) is a progressive neurodegenerative disorder and the main cause of dementia in the elderly population. Since the treatment of AD has been associated with the activity of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE), their inhibitors remain the main focus of AD investigations. In this study we evaluated cholinesterase inhibitory activity of 14 bicyclo[3.2.1]octene/octadiene derivatives and naturally occurring sesquiterpene alcohol cedrol. These 14 compounds have been efficiently and ecologically prepared by a photochemical approach in batch photochemical reactors. Various compounds with the bicyclo[3.2.1]octene skeleton have already been successfully evaluated for treatment of central nervous system disorders and AD. Among the tested polycyclic derivatives, compounds 4-[ (9 S) -tricyclo [6.3.1.0(2,7)]dodeca-2 ,4 ,6,10-tetraen-9-yl]pyridine (3) and (11 S) -11- (4-chlorophenyl)-12- [( E) - 2- (4-chlorophenyl) ethenyl]tricyclo[6.3.1.0(2,7)] idodeca-2,4,6,9-tetraene (6) showed the best inhibitory activity on BChE (IC50 = 8.8 mu M) and AChE (IC50 = 17.5 mu M), respectively.