Design and synthesis of novel 3,5-bis-N-(aryl/heteroaryl) carbamoyl-4-aryl-1,4-dihydropyridines as small molecule BACE-1 inhibitors
摘要:
Alzheimer disease (AD) is a neuronal dementia for which no treatment has been consolidated yet. Major pathologic hallmark of AD is the aggregated extracellular amyloid-beta plaques in the brains of disease sufferers. A beta-peptide is a major component of amyloid plaques and is produced from amyloid precursor protein (APP) via the proteolysis action. An aspartyl protease known as beta-site amyloid precursor protein cleaving enzyme (BACE-1) is responsible for this proteolytic action. Distinctive role of BACE-1 in AD pathogenesis has made it a validated target to develop anti-Alzheimer agents. Our structure-based virtual screening method led to the synthesis of novel 3,5-bis-N-(aryl/heteroaryl) carbamoyl-4-aryl-1,4-dihydropyridine BACE-1 inhibitors (6a-6p; in vitro hits). Molecular docking and DFT-based ab initio studies using B3LYP functional in association with triple-zeta basis set (TZV) proposed binding mode and binding energies of ligands in the active site of the receptor. In vitro BACE-1 inhibitory activities were determined by enzymatic fluorescence resonance energy transfer (FRET) assay. Most of the synthesized dihydropyridine scaffolds were active against BACE-1 while 6d, 6k, 6n and 6a were found to be the most potent molecules with IC50 values of 4.21, 4.27, 4.66 and 6.78 mu M, respectively. Superior BACE-1 inhibitory activities were observed for dihydropyridine derivatives containing fused/nonfused thiazole containing groups, possibly attributing to the additional interactions with S2-S3 subpocket residues. Relatively reliable correlation between calculated binding energies and experimental BACE-1 inhibitory activities was achieved (R-2 = 0.51). Moreover, compounds 6d, 6k, 6n and 6a exhibited relatively no calcium channel blocking activity with regard to nifedipine suggesting them as appropriate candidates for further modification(s) to BACE-1 inhibitory scaffolds. (C) 2013 Elsevier Ltd. All rights reserved.
An efficient and modified biginelli one-pot synthesis of new isoxazole substitted 3,4-dihydropyrimidin-2(1<i>H</i>)-ones and thiones catalyzed by VCl<sub>3</sub>
An efficient and modifiedBiginellione-potsynthesis of new-isoxazole substituted 3,4-dihydropyrimidin-2(1H)-ones and thiones from aromatic aldehydes, ketoamide and urea/thiourea in acetonitrile using VCl3 as the catalyst is described.
Alzheimer disease (AD) is a neuronal dementia for which no treatment has been consolidated yet. Major pathologic hallmark of AD is the aggregated extracellular amyloid-beta plaques in the brains of disease sufferers. A beta-peptide is a major component of amyloid plaques and is produced from amyloid precursor protein (APP) via the proteolysis action. An aspartyl protease known as beta-site amyloid precursor protein cleaving enzyme (BACE-1) is responsible for this proteolytic action. Distinctive role of BACE-1 in AD pathogenesis has made it a validated target to develop anti-Alzheimer agents. Our structure-based virtual screening method led to the synthesis of novel 3,5-bis-N-(aryl/heteroaryl) carbamoyl-4-aryl-1,4-dihydropyridine BACE-1 inhibitors (6a-6p; in vitro hits). Molecular docking and DFT-based ab initio studies using B3LYP functional in association with triple-zeta basis set (TZV) proposed binding mode and binding energies of ligands in the active site of the receptor. In vitro BACE-1 inhibitory activities were determined by enzymatic fluorescence resonance energy transfer (FRET) assay. Most of the synthesized dihydropyridine scaffolds were active against BACE-1 while 6d, 6k, 6n and 6a were found to be the most potent molecules with IC50 values of 4.21, 4.27, 4.66 and 6.78 mu M, respectively. Superior BACE-1 inhibitory activities were observed for dihydropyridine derivatives containing fused/nonfused thiazole containing groups, possibly attributing to the additional interactions with S2-S3 subpocket residues. Relatively reliable correlation between calculated binding energies and experimental BACE-1 inhibitory activities was achieved (R-2 = 0.51). Moreover, compounds 6d, 6k, 6n and 6a exhibited relatively no calcium channel blocking activity with regard to nifedipine suggesting them as appropriate candidates for further modification(s) to BACE-1 inhibitory scaffolds. (C) 2013 Elsevier Ltd. All rights reserved.
Solid‐Supported Synthesis of Isoxazole‐Substituted 1,4‐Dihydropyridines by Modified Hantzsch Method and Their Aromatization
Abstract The synthesis of isoxazole‐substitutedHantzsch 1,4‐dihydropyridines has been achieved by modified Hantzsch procedure for the first time by utilizing ketoamides in place of keto esters on a neutral alumina support in excellent yields. These 1,4‐dihydropyridines are aromatized to the corresponding pyridines in high yields by using bismuth subnitrate (BiONO3) adsorbed on acidic alumina at ambient