Regioselective Nucleophilic Aromatic Substitution: Theoretical and Experimental Insights into 4-Aminoquinazoline Synthesis as a Privileged Structure in Medicinal Chemistry.

The 4-aminoquinazoline scaffold is a privileged structure in medicinal chemistry. Regioselective nucleophilic aromatic substitution (SAr) for replacing the chlorine atom at the 4-position of 2,4-dichloroquinazoline precursors is well documented in the scientific literature and has proven useful in synthesizing 2-chloro-4-aminoquinazolines and/or 2,4-diaminoquinazolines for various therapeutic applications. While numerous reports describe reaction conditions involving different nucleophiles, solvents, temperatures, and reaction times, discussions on the regioselectivity of the SAr step remain scarce.

Histone deacetylase inhibition mitigates cognitive deficits and astrocyte dysfunction induced by amyloid-β (Aβ) oligomers.

Background And Purpose: Inhibitors of histone deacetylases (iHDACs) are promising drugs for neurodegenerative diseases. We have evaluated the therapeutic potential of the new iHDAC LASSBio-1911 in Aβ oligomer (AβO) toxicity models and astrocytes, key players in neuroinflammation and Alzheimer's disease (AD).

Experimental Approach: Astrocyte phenotype and synapse density were evaluated by flow cytometry, Western blotting, immunofluorescence and qPCR, in vitro and in mice.

Remapping the Chemical Space and the Pharmacological Space of Drugs: What Can We Expect from the Road Ahead?

This work examines the current landscape of drug discovery and development, with a particular focus on the chemical and pharmacological spaces. It emphasizes the importance of understanding these spaces to anticipate future trends in drug discovery. The use of cheminformatics and data analysis enabled in silico exploration of these spaces, allowing a perspective of drugs, approved drugs after 2020, and clinical candidates, which were extracted from the newly released ChEMBL34 (March 2024).

Molecular hybridization: a powerful tool for multitarget drug discovery.

Introduction: The current drug discovery paradigm of 'one drug, multiple targets' has gained attention from both the academic medicinal chemistry community and the pharmaceutical industry. This is in response to the urgent need for effective agents to treat multifactorial chronic diseases. The molecular hybridization strategy is a useful tool that has been widely explored, particularly in the last two decades, for the design of multi-target drugs.

The Magic Methyl and Its Tricks in Drug Discovery and Development.

One of the key scientific aspects of small-molecule drug discovery and development is the analysis of the relationship between its chemical structure and biological activity. Understanding the effects that lead to significant changes in biological activity is of paramount importance for the rational design and optimization of bioactive molecules. The "methylation effect", or the "magic methyl" effect, is a factor that stands out due to the number of examples that demonstrate profound changes in either pharmacodynamic or pharmacokinetic properties.

Methyl Effect on the Metabolism, Chemical Stability, and Permeability Profile of Bioactive -Sulfonylhydrazones.

Sulfonylhydrazones are privileged structures with multifaceted pharmacological activity. Exploring the hypoglycemic properties of these organic compounds, we previously revealed a new series of -sulfonylhydrazones (NSH) as antidiabetic drug candidates. Here, we evaluated the microsomal metabolism, chemical stability, and permeability profile of these NSH prototypes, focusing on the pharmacokinetic differences in -methylated and non--methylated analogs.

Design, Synthesis and Pharmacological Evaluation of Novel Conformationally Restricted -arylpiperazine Derivatives Characterized as D/D Receptor Ligands, Candidates for the Treatment of Neurodegenerative Diseases.

Most neurodegenerative diseases are multifactorial, and the discovery of several molecular mechanisms related to their pathogenesis is constantly advancing. Dopamine and dopaminergic receptor subtypes are involved in the pathophysiology of several neurological disorders, such as schizophrenia, depression and drug addiction. For this reason, the dopaminergic system and dopamine receptor ligands play a key role in the treatment of such disorders.

Investigating the Molecular Basis for the Selective Inhibition of Aldehyde Dehydrogenase 2 by the Isoflavonoid Daidzin.

Background: ALDH-2 has been considered an important molecular target for the treatment of drug addiction due to its involvement in the metabolism of the neurotransmitter dopamine: however, the molecular basis for the selective inhibition of ALDH-2 versus ALDH-1 should be better investigated to enable a more pragmatic approach to the design of novel ALDH-2 selective inhibitors.

Objective: In the present study, we investigated the molecular basis for the selective inhibition of ALDH-2 by the antioxidant isoflavonoid daidzin (IC50 = 0.15 μM) compared to isoform 1 of ALDH through molecular dynamics studies and semiempirical calculations of the enthalpy of interaction.

Turning Donepezil into a Multi-Target-Directed Ligand through a Merging Strategy.

Thanks to the widespread use and safety profile of donepezil (1) in the treatment of Alzheimer's disease (AD), one of the most widely adopted multi-target-directed ligand (MTDL) design strategies is to modify its molecular structure by linking a second fragment carrying an additional AD-relevant biological property. Herein, supported by a proposed combination therapy of 1 and the quinone drug idebenone, we rationally designed novel 1-based MTDLs targeting Aβ and oxidative pathways. By exploiting a bioisosteric replacement of the indanone core of 1 with a 1,4-naphthoquinone, we ended up with a series of highly merged derivatives, in principle devoid of the "physicochemical challenge" typical of large hybrid-based MTDLs.

N-Acylhydrazones as drugs.

Over the last two decades, N-acylhydrazone (NAH) has been proven to be a very versatile and promising motif in drug design and medicinal chemistry. Herein, we discuss the current and future challenges in the emergence of bioactive NAH-based scaffolds and to developing strategies to overcome the failures in drug discovery. The NAH-related approved drugs nitrofurazone, nitrofurantoin, carbazochrome, testosterone 17-enanthate 3-benzilic acid hydrazine, nifuroxazide, dantrolene, and azumolene are already used as therapeutics in various countries.

An Unusual Intramolecular Halogen Bond Guides Conformational Selection.

PIK-75 is a phosphoinositide-3-kinase (PI3K) α-isoform-selective inhibitor with high potency. Although published structure-activity relationship data show the importance of the NO and the Br substituents in PIK-75, none of the published studies could correctly determine the underlying reason for their importance. In this publication, we report the first X-ray crystal structure of PIK-75 in complex with the kinase GSK-3β.

Structural basis for the agonist action at free fatty acid receptor 1 (FFA1R or GPR40).

G-protein-coupled receptor 40 (GPR40) was recently identified as an interesting target for treatment of type 2 diabetes. The high level of expression in pancreatic beta cells and the dependence of glucose on stimulating the secretion of insulin led to great excitement in this field. The identification of this target was followed by the development of a series of agonists with great potential for the treatment of diabetes.