Thermodynamics of the interaction between spike protein of severe acute respiratory syndrome-coronavirus-2 and the receptor of human angiotensin converting enzyme 2. Effects of possible ligands

Since the end of 2019, the coronavirus SARS-CoV-2 has caused more than 1000000 deaths all over the world and still lacks a medical treatment despite the attention of the whole scientific community. Human angiotensin-converting enzyme 2 (ACE2) was recently recognized as the transmembrane protein that serves as the point of entry of SARS-CoV-2 into cells, thus constituting the first biomolecular event leading to COVID-19 disease. Here, by means of a state-of-the-art computational approach, we propose a rational evaluation of the molecular mechanisms behind the formation of the protein complex. Moreover, the free energy of binding between ACE2 and the active receptor binding domain of the SARS-CoV-2 spike protein is evaluated quantitatively, providing for the first time the thermodynamics of virus?receptor recognition. Furthermore, the action of different ACE2 ligands is also examined in particular in their capacity to disrupt SARS-CoV-2 recognition, also providing via a free energy profile the quantification of the ligand-induced decreased affinity. These results improve our knowledge on molecular grounds of the SARS-CoV-2 infection and allow us to suggest rationales that could be useful for the subsequent wise molecular design for the treatment of COVID-19 cases

Synthesis, antioxidant properties and neuroprotection of α-phenyl-tert-butylnitrone derived HomoBisNitrones in in vitro and in vivo ischemia models

We herein report the synthesis, antioxidant power and neuroprotective properties of nine homo-bis-nitrones HBNs1–9 as alpha-phenyl-N-tert-butylnitrone (PBN) analogues for stroke therapy. In vitro neuroprotection studies of HBNs1–9 against Oligomycin A/Rotenone and in an oxygen-glucose-deprivation model of ischemia in human neuroblastoma cell cultures, indicate that (1Z,1′Z)-1,1′-(1,3-phenylene)bis(N-benzylmethanimine oxide) (HBN6) is a potent neuroprotective agent that prevents the decrease in neuronal metabolic activity (EC = 1.24 ± 0.39 μM) as well as necrotic and apoptotic cell death. HBN6 shows strong hydroxyl radical scavenger power (81%), and capacity to decrease superoxide production in human neuroblastoma cell cultures (maximal activity = 95.8 ± 3.6%), values significantly superior to the neuroprotective and antioxidant properties of the parent PBN. The higher neuroprotective ability of HBN6 has been rationalized by means of Density Functional Theory calculations. Calculated physicochemical and ADME properties confirmed HBN6 as a hit-agent showing suitable drug-like properties. Finally, the contribution of HBN6 to brain damage prevention was confirmed in a permanent MCAO setting by assessing infarct volume outcome 48 h after stroke in drug administered experimental animals, which provides evidence of a significant reduction of the brain lesion size and strongly suggests that HBN6 is a potential neuroprotective agent against stroke.We would like to thank Soledad Martinez Montero for the excellent technical assistance. This work was supported by grants from the Spanish Ministry of Economy and Competitiveness (SAF2015-65586-R to JMC; CTQ2016- 78205-P and CTQ2016-81797-REDC to IF, and NEUROCENTRO-CM S2017/BMD3760 to RMM and DNG), and Camilo José Cela University (UCJC-2018-04) to MJOG. DDI thanks the University of Alcalá and Spanish Ministry of Science, Innovation and Universities for pre-doctoral FPU grants. BCG thanks the Spanish Ministr

Exploring the Potential of Sulfonamide-Dihydropyridine Hybrids as Multitargeted Ligands for Alzheimer’s Disease Treatment

Alzheimer’s disease (AD) is a multifactorial neurodegenerative disease that has a heavy social and economic impact on all societies and for which there is still no cure. Multitarget-directed ligands (MTDLs) seem to be a promising therapeutic strategy for finding an effective treatment for this disease. For this purpose, new MTDLs were designed and synthesized in three steps by simple and cost-efficient procedures targeting calcium channel blockade, cholinesterase inhibition, and antioxidant activity. The biological and physicochemical results collected in this study allowed us the identification two sulfonamide-dihydropyridine hybrids showing simultaneous cholinesterase inhibition, calcium channel blockade, antioxidant capacity and Nrf2-ARE activating effect, that deserve to be further investigated for AD therapy.This work was supported by the Regional Council of Franche-Comté (2022Y-13659 and 13660 Accurate Project).Peer reviewe

Acetylcholinesterase Inhibition of Diversely Functionalized Quinolinones for Alzheimer's Disease Therapy

In this communication, wereport the synthesis and cholinesterase (ChE)/monoamine oxidase (MAO) inhibition of 19 quinolinones (QN1-19) and 13 dihydroquinolinones (DQN1-13) designed as potential multitarget small molecules (MSM) for Alzheimer¿s disease therapy. Contrary to our expectations, none of them showed significant human recombinant MAO inhibition, but compounds QN8, QN9, and DQN7 displayed promising human recombinant acetylcholinesterase (hrAChE) and butyrylcholinesterase (hrBuChE) inhibition. In particular, molecule QN8 was found to be a potent and quite selective non-competitive inhibitor of hrAChE (IC50 = 0.29 M), with Ki value in nanomolar range (79 nM). Pertinent docking analysis confirmed this result, suggesting that this ligand is an interesting hit for further investigation.R.A., M.S., P.B., and K.M. were supported by European Regional Development Fund/European Social Fund (ERDF/ESF, project PharmaBrain, no. CZ.02.1.01/0.0/0.0/16_025/0007444), University of Hradec Kralove (no. SV2113-2019, VT2019-2021), and EU COST action CA15135 MuTaLig. J.M.C. thanks Ministerio de Economía (MINECO, SAF2015-65586-R) and Universidad Camilo José Cela (UCJC, grants UCJC 2020-03, and UCJC 2020-33) for support

Multipotent cholinesterase/monoamine oxidase inhibitors for the treatment of Alzheimer's disease: design, synthesis, biochemical evaluation, ADMET, molecular modeling, and QSAR analysis of novel donepezil-pyridyl hybrids

The design, synthesis, and biochemical evaluation of donepezil-pyridyl hybrids (DPHs) as multipotent cholinesterase (ChE) and monoamine oxidase (MAO) inhibitors for the potential treatment of Alzheimer's disease (AD) is reported. The 3D-quantitative structure-activity relationship study was used to define 3D-pharmacophores for inhibition of MAO A/B, acetylcholinesterase (AChE), and butyrylcholinesterase (BuChE) enzymes and to design DPHs as novel multi-target drug candidates with potential impact in the therapy of AD. DPH14 (Electrophorus electricus AChE [EeAChE]: half maximal inhibitory concentration [IC50] = 1.1 +/- 0.3 nM; equine butyrylcholinesterase [eqBuChE]: IC50 = 600 +/- 80 nM) was 318-fold more potent for the inhibition of AChE, and 1.3-fold less potent for the inhibition of BuChE than the reference compound ASS234. DPH14 is a potent human recombinant BuChE (hBuChE) inhibitor, in the same range as DPH12 or DPH16, but 13.1-fold less potent than DPH15 for the inhibition of human recombinant AChE (hAChE). Compared with donepezil, DPH14 is almost equipotent for the inhibition of hAChE, and 8.8-fold more potent for hBuChE. Concerning human monoamine oxidase (hMAO) A inhibition, only DPH9 and 5 proved active, compound DPH9 being the most potent (IC50 [MAO A] = 5,700 +/- 2,100 nM). For hMAO B, only DPHs 13 and 14 were moderate inhibitors, and compound DPH14 was the most potent (IC50 [MAO B] = 3,950 +/- 94 nM). Molecular modeling of inhibitor DPH14 within EeAChE showed a binding mode with an extended conformation, interacting simultaneously with both catalytic and peripheral sites of EeAChE thanks to a linker of appropriate length. Absortion, distribution, metabolism, excretion and toxicity analysis showed that structures lacking phenyl-substituent show better druglikeness profiles; in particular, DPHs13-15 showed the most suitable absortion, distribution, metabolism, excretion and toxicity properties. Novel donepezil-pyridyl hybrid DPH14 is a potent, moderately selective hAChE and selective irreversible hMAO B inhibitor which might be considered as a promising compound for further development for the treatment of AD

Multitarget-directed ligands combining cholinesterase and monoamine oxidase inhibition with histamine H3R antagonism for neurodegenerative diseases

J.M.C. thanks MINECO (SAF2012-33304 and SAF2015-65586-R). J.M.C., F.L.M., and A.R. thank UCJC for grants 2015-12, 2014-35, and 2015-21, respectively. J.E. thanks the Fondo de Investigaciones Sanitarias (FIS) (ISCIII/FEDER) (Programa Miguel Servet: CP14/00008 and PI16/00735) and Fundación Mutua Madrileña. O.S. and J.J. thank MHCZ-DRO (UHHK 00179906) for support. R.R.R., H.S., and J.M.C. acknowledge the EU COST Actions CM1103 and CM15135. E.P. and H.S. thank the German Research Foundation (DFG; PRO 1405/2-2, PRO 1405/4-1, SFB 1039 A07, and INST208/664-1).The therapy of complex neurodegenerative diseases requires the development of multitarget-directed drugs (MTDs). Novel indole derivatives with inhibitory activity towards acetyl/butyrylcholinesterases and monoamine oxidases A/B as well as the histamine H3 receptor (H3R) were obtained by optimization of the neuroprotectant ASS234 by incorporating generally accepted H3R pharmacophore motifs. These small-molecule hits demonstrated balanced activities at the targets, mostly in the nanomolar concentration range. Additional in vitro studies showed antioxidative neuroprotective effects as well as the ability to penetrate the blood–brain barrier. With this promising in vitro profile, contilisant (at 1 mg kg−1 i.p.) also significantly improved lipopolysaccharide-induced cognitive deficits.PostprintPeer reviewe

Synthesis, structural, conformational and pharmacological study of some carbamates derived from 8-methyl-8-azabicyclo[3.2.1]octan-3α-ol

A series of benzimidazole, thiazole, and benzothiazole carbamates derived from 8-methyl-8-azabicyclo[3.2.1]octan-3α-ol hydrochloride was synthesized and studied by 1H, 13C NMR and IR spectroscopy. To assist in the interpretation of the spectroscopic data, the free bases were obtained and studied by IR spectroscopy in different media. As in related compounds, spectroscopic results showed that two different carbamates (1-carbamate or 2-carbamate) could be obtained in the case of the hydrochlorides of benzimidazole derivatives. The hydrochlorides studied displayed in DMSO-d 6 solution a preferred flattened chair-envelope conformation with the NCH3 substituent in an equatorial disposition. Pharmacological assays in vitro and in vivo were drawn to evaluate 5-HT3 activity. © 2011 Elsevier B.V. All rights reserved.The authors thank Dr. A. Orjales (FAES S.A. Laboratories, Bilbao, Spain) for the pharmacologicalstudies.Peer Reviewe

Synthesis, spectroscopic, structural and conformational study of some tri-substituted ureas derived from N-methylpiperazine containing phenyl and N-heterocyclic substituents

A series of tri-substituted ureas containing an N-methylpiperazine moiety as well as phenyl and N-heterocyclic substituents were synthesized and studied by 1H, 13C NMR and IR spectroscopies. From 1H and 13C NMR data, in CDCl3 solution at room temperature, a fast inter-conversion of the piperazine ring with the N-CH3 group in equatorial position can be proposed. Amino–imino tautomerism is observed for both thiazole and benzothiazole derivatives. Moreover, with the exception of the imino form of the thiazole derivative, the aryl substituted N-carbamoyl group rotates freely. IR data show that the compounds adopt a planar trans conformation of the single bondCOsingle bondNHsingle bond moiety

Synthesis, spectroscopic, structural and conformational study of some ureas derived from N-methylpiperazine

Trabajo presentado en el 31st European Congress on Molecular Spectroscopy (EUCMOS 2012), celebrado en Cluj-Napoca (Rumanía) del 26 al 31 de agosto de 201