New cholinesterase inhibitors for Alzheimer’s disease: Structure Activity Studies (SARs) and molecular docking of isoquinolone and azepanone derivatives

Docking-Based Prediction of Peptide Binding to MHC Proteins

Major histocompatibility complex (MHC) proteins are the most polymorphic and polygenic proteins in humans. They bind peptides, derived from cleavage of different pathogenic antigens, and are responsible for presenting them to T cells. The peptides recognized by the T cell receptors are denoted as epitopes and they trigger an immune response.In this chapter, we describe a docking protocol for predicting the peptide binding to a given MHC protein using the software tool GOLD. The protocol starts with the construction of a combinatorial peptide library used in the docking and ends with the derivation of a quantitative matrix (QM) accounting for the contribution of each amino acid at each peptide position.

Construction of Spirooxindole Analogues Engrafted with Indole and Pyrazole Scaffolds as Acetylcholinesterase Inhibitors

Twenty-five new hits of spirooxindole analogs 8a-y engrafted with indole and pyrazole scaffolds were designed and constructed via a [3+2]cycloaddition (32CA) reaction starting from three components: new chalcone-based indole and pyrazole scaffolds 5a-d, substituted isatins 6a-c, and secondary amines 7a-d. The potency of the compounds were assessed in modulating cholinesterase (AChE) activity using Ellman's method. Compounds 8i and 8y showed the strongest acetylcholine esterase inhibition (AChEI) with IC50 values of 24.1 and 27.8 μM, respectively. Molecular docking was used to study their interaction with the active site of hAChE.

In silico modeling for dual inhibition of acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzymes in Alzheimer's disease

In this research, we have implemented two-dimensional quantitative structure-activity relationship (2D-QSAR) modeling using two different datasets, namely, acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzyme inhibitors. A third dataset has been derived based on their selectivity and used for the development of partial least squares (PLS) based regression models. The developed models were extensively validated using various internal and external validation parameters. The features appearing in the model against AChE enzyme suggest that a small ring size, higher number of -CH2- groups, higher number of secondary aromatic amines and higher number of aromatic ketone groups may contribute to the inhibitory activity. The features obtained from the model against BuChE enzyme suggest that the sum of topological distances between two nitrogen atoms, higher number of fragments X-C(=X)-X, higher number of secondary aromatic amides, fragment R--CR-X may be more favorable for inhibition. The features obtained from selectivity based model suggest that the number of aromatic ethers, unsaturation content relative to the molecular size and molecular shape may be more specific for the inhibition of the AChE enzyme in comparison to the BuChE enzyme. Moreover, we have implemented the molecular docking studies using the most and least active molecules from the datasets in order to identify the binding pattern between ligand and target enzyme. The obtained information is then correlated with the essential structural features associated with the 2D-QSAR models.

Synthesis, acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) activities, and molecular docking studies of a novel compound based on combination of flurbiprofen and isoniazide

A novel compound (1) shows ∼2.5 and ∼1.7 times enhanced AChE inhibition activity and BuChE inhibition activity respectively compared to flurbiprofen and standard drug (i.e. physostigmine). It has also been confirmed by comparative AutoDock studies.

Sequential alcohol oxidation/putative homo Claisen–Tishchenko-type reaction to give esters: a key process in accessing novel biologically active lactone macrocycles

We report an efficient methodology for the direct oxidative esterification of primary alcohols to diether-esters using pyridinium chlorochromate (PCC).