Synthesis, spectroscopic characterizations, DFT calculations and molecular docking studies of new quinoline-oxirane/piperidine/morpholine hybrids from quinoline gem‑dicyanoepoxide

Abstract

We report in this paper a combined experimental and theoretical study of new 2-quinolone-piperidine (5a) and -morpholine (5b-c) hybrids from3-(2-chloroquinolin-3-yl) oxirane-2,2-dicarbonitrile (3) via an epoxide ring opening reaction using appropriate synthetic routes. In a parallel approach, a tandem consecutive process was carried out, without isolation of the brominated intermediate for the synthesis of 2-quinolone-morpholine (5c). The prepared compounds were fully characterized by conventional analytical techniques, and single-crystal X-ray diffraction for compound 5c was also reported. To increase the accuracy of experimental results, DFT and TD-DFT calculations were performed including molecular structure optimization, NMR, optical and electronic data, frontier molecular orbitals and molecular descriptors. In addition, a molecular docking calculation was carried out to estimate the affinity between compounds 3, 5a, 5b and 5c and Acetylcholinesterase (AChE)/ Butyrylcholinesterase (BuChE). Theoretical results are in agreement with the experimental.