Quinoline containing chalcone derivatives as cholinesterase inhibitors and their in silico modeling studies.

Cholinesterases (ChEs) play a vital role in regulating cholinergic transmission. Inhibition of ChEs is thought to be an emerging and useful therapeutic target for neurodegenerative disorders through restoration of acetylcholine (ACh) levels in the brain (e.g. Alzheimer's disease). To increase the chemical diversity of cholinesterase inhibitors, a series of quinoline chalcones derivatives were tested against acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) isoenzymes. All tested compounds (4a-1; 5a-s) exhibited inhibitory activities against AChE and BChE to a considerable extent. Molecular docking studies were performed by using homology models on both AChE and BChE isoenzymes with the aim of exploring probable binding modes of the most potent inhibitor. In order to evaluate drug likeness of newly tested molecules, we carried out in-silico ADME evaluation. All compounds displayed favourable ADME findings which predict good oral bioavailability of these derivatives. Due to an excellent ADME profile the tested compounds were predicted to be safer which can be considered as novel cholinesterase inhibitors.

Monoamine Oxidase Inhibition and Molecular Modeling Studies of Piperidyl-thienyl and 2-Pyrazoline Derivatives of Chalcones.

A series of piperidyl-thienyl & 2-pyrazoline derivatives of quinolyl-thienyl chalcones were tested to observe the structural characteristics for the monoamine oxidase inhibitory (MAO) activity. In both these series, a diverse range of substituted thiophenes are used which enable the structure activity relationship. The compounds showed enhanced inhibition against MAO-A & B as compared to reference compounds. Compound 1c exhibited most potent MAO-A inhibition having IC50 value of 0.062 µM, while 1j showed excellent inhibitory potency against MAO-B having IC50 value of 0.088 µM. The present investigation demonstrated that among piperidyl-thienyl chalcones, almost all the compounds exhibit significant MAO-A inhibition, thus may have antidepressant activity. Whereas among the 2-pyrazoline derivatives of chal-cones, many compounds revealed MAOB inhibition and hence may be applied in the control of senile dementia. Molecular docking studies were carried out against human MAO-A and MAO-B to rationalize important binding site interactions.