Conformational and NBO studies of serotonin as a radical scavenger. Changes induced by the OH group

摘要

Serotonin (5-hydroxytryptamine, SER) is a neurotransmitter that affects many different processes within the human body. We studied the conformational space of SER, and explored in depth the significant stereoelectronic features for the structure stabilization and antioxidant activity. Forty-eight equilibrium structures were described at the B3LY13/6-311++G(d,p) level, characterizing four non-previously reported conformers. Electron distributions were analyzed by topological QTAIM (Quantum Theory of atoms in molecules) and natural bond orbital (NBO) studies. The study was supplemented by an exploration of molecular electrostatic potential (MEP). Intramolecular hydrogen interactions were also investigated: N10 center dot center dot center dot H-C4 or N10 center dot center dot center dot H-C2 hydrogen bondings were depicted in 5 conformers.