Theoretical study of structure spectral properties of Tacrine as Alzheimer drug

Tacrine (9-amino-1,2,3,4-tetrahydroacridine) as a reversible inhibitor of acetylcholinesterase (AChE),was the first drug for the symptomatic treatment of Alzheimer’s disease (AD). NMR structuredetermination still presents some considerable challenges: the method is limited to systems ofrelatively small molecular mass, data collection times are long, data analysis remains a lengthyprocedure, and it is difficult to evaluate the quality of the final structures but calculation of a structureitself has become extremely rapid, and new labeling methods have significantly improved bothspectral quality and automated analysis, whilst rigorous standards and data formats affordcompatibility of different software packages. In this theoretical study, we used HF and DFT (BLYP,B3LYP) method for chemical shift nucleus magnetic resonance DFT-NMR. The basis set used were6–31G, 6–31G** and 6-31G++. The results show a reasonably good correlation between calculatedand experimental chemical shifts. Agreement of experiment and calculated data suggesting thatstudies of drug structures can be pursued with some degree of confidence with this level of theory.