Synthesis, characterization and cholinesterase enzymes inhibitory activity of 1-[3-methyl-5-(2,6,6-trimethyl-cyclohex-1-enyl)-4,5-dihydro-pyrazol-1-yl]-ethanone

• Published in: Journal of molecular structure Vol. 1049; pp. 488 - 493
• Main Authors: Mehdi, Sayed Hasan, Ghalib, Raza Murad, Hashim, Rokiah, da Silva, M. Fátima C. Guedes, Sulaiman, Othman, Murugaiyah, Vikneswaran, Marimuthu, Mani Maran, Naqvi, Mehnaz
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 08.10.2013
• Subjects: 1-[3-Methyl-5-(2,6,6-trimethyl-cyclohex-1-enyl)-4,5-dihydro-pyrazol-1-yl]-ethanone; acetylcholinesterase; Acetylcholinesterase, butyrylcholinesterase; cholinesterase; Crystal structure; Fourier transform infrared spectroscopy; Inter-molecular hydrogen bonding; NMR spectra; nuclear magnetic resonance spectroscopy; physostigmine; X-ray diffraction; 1-[3-Methyl-5-(2,6,6-trimethyl-cyclohex-1-enyl)-4,5-dihydro-pyrazol-1-yl]-ethanone; Inter-molecular hydrogen bonding; NMR spectra; Acetylcholinesterase, butyrylcholinesterase; Crystal structure
• ISSN: 0022-2860; 1872-8014
• DOI: 10.1016/j.molstruc.2013.06.049

The twisting of the cyclohexene ring relative to the pyrazole one gives rise to a medium intense intramolecular interaction of a methyl hydrogen of the former with the centroid of the latter. [Display omitted] •1-[3-Methyl-5-(2,6,6-trimethyl-cyclohex-1-enyl)-4,5-dihydro-pyrazol-1-yl]-ethanone was synthesized.•X-ray crystallography, 1H, 13CNMR and IR spectral studies confirmed the structure.•Inhibitory activity against acetylcholinesterase and butyrylcholinesterase enzyme. The crystal structure of the title compound, 1-[3-methyl-5-(2,6,6-trimethyl-cyclohex-1-enyl)-4,5-dihydro-pyrazol-1-yl]-ethanone has been determined by single crystal X-ray diffraction. It crystallizes in the orthorhombic space group P212121. The FTIR as well as the 1H and 13C NMR spectra of the compound were also recorded and briefly discussed. Compound 1 demonstrated good inhibitory activity against butyrylcholinesterase (BChE; IC50=46.42μM) comparable to physostigmine. However it showed moderate inhibitory activity against acetylcholinesterase (AChE; IC50=157.31μM). It showed moderate inhibitory activity against acetylcholinesterase and selective inhibitory activity towards butyrylcholinesterase enzyme.