A Quantum Chemical Study on Alkaloid Molecules Derived from Nicotinic Acid

A quantum chemical studies were conducted on nicotine, nornicotine, anabasine, arecholine, ricinine, cotinine, -nicotrine, anatabine and myosmine molecules, which are alkaloids derived from or related to nicotine acid, using ab initio methods. As a result, we have proposed a molecular electrostatic potential diagram in the form of a 3D mapped isosurface and a net charge of molecules, which predict or proposed a specific reaction site. The average electrodonating power obtained by the frontier energy of alkaloid molecules was 1.173171, which was larger than the average electroaccepting power of 0.599333. Protonation reactions at specific reaction sites predicted for alkaloid molecules showed that the changes in free energy and enthalpy ranged from -149.257 to -655.769 kJ/mol and -140.970 to -657.806 kJ/mol, respectively and were spontaneous and exothermic reactions. The data and methodology of the research results are expected to be useful for future research on alkaloids.