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de Souza LG, Penna EA, Rosa AS, da Silva JC, Schaeffer E, Guimarães JV, de Paiva DM, de Souza VC, Ferreira VNS, Souza DDC, Roxo S, Conceição GB, Constant LEC, Frenzel GB, Landim MJN, Baltazar MLP, Silva CC, Brand ALM, Nunes JS, Montagnoli TL, Zapata-Sudo G, Alves MA, Allonso D, Goliatt PVZC, Miranda MD, da Silva AJM. Benzocarbazoledinones as SARS-CoV-2 Replication Inhibitors: Synthesis, Cell-Based Studies, Enzyme Inhibition, Molecular Modeling, and Pharmacokinetics Insights. Viruses 2024; 16:1768. [PMID: 39599882 PMCID: PMC11598835 DOI: 10.3390/v16111768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/02/2024] [Revised: 11/04/2024] [Accepted: 11/07/2024] [Indexed: 11/29/2024] Open
Abstract
Endemic and pandemic viruses represent significant public health challenges, leading to substantial morbidity and mortality over time. The COVID-19 pandemic has underscored the urgent need for the development and discovery of new, potent antiviral agents. In this study, we present the synthesis and anti-SARS-CoV-2 activity of a series of benzocarbazoledinones, assessed using cell-based screening assays. Our results indicate that four compounds (4a, 4b, 4d, and 4i) exhibit EC50 values below 4 μM without cytotoxic effects in Calu-3 cells. Mechanistic investigations focused on the inhibition of the SARS-CoV-2 main protease (Mpro) and papain-like protease (PLpro) have used enzymatic assays. Notably, compounds 4a and 4b showed Mpro inhibition activity with IC50 values of 0.11 ± 0.05 and 0.37 ± 0.05 µM, respectively. Furthermore, in silico molecular docking, physicochemical, and pharmacokinetic studies were conducted to validate the mechanism and assess bioavailability. Compound 4a was selected for preliminary drug-likeness analysis and in vivo pharmacokinetics investigations, which yielded promising results and corroborated the in vitro and in silico findings, reinforcing its potential as an anti-SARS-CoV-2 lead compound.
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de Oliveira NS, de Souza LG, de Almeida VM, Barreto ARR, Carvalho-Gondim F, Schaeffer E, Santos-Filho OA, Rossi-Bergmann B, da Silva AJM. Synthesis and evaluation of hybrid sulfonamide-chalcones with potential antileishmanial activity. Arch Pharm (Weinheim) 2024; 357:e2300440. [PMID: 38048546 DOI: 10.1002/ardp.202300440] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2023] [Revised: 10/26/2023] [Accepted: 11/14/2023] [Indexed: 12/06/2023]
Abstract
Leishmaniasis is an emerging tropical infectious disease caused by a protozoan parasite of the genus Leishmania. In this work, the molecular hybridization between a trimethoxy chalcone and a sulfonamide group was used to generate a series of sulfonamide-chalcones. A series of eight sulfonamide-chalcone hybrids were made with good yields (up to 95%). These sulfonamide-chalcones were tested against promastigotes of Leishmania amazonensis and cytotoxicity against mouse macrophages, which showed good antileishmanial activity with IC50 = 1.72-3.19 µM. Three of them (10c, 10g, and 10h) were also highly active against intracellular amastigotes and had a good selectivity index (SI > 9). Thus, those three compounds were docked in the cytosolic tryparedoxin peroxidase (cTXNPx) enzyme of the parasite, and molecular dynamics simulations were carried out. This enzyme was selected as a target protein for the sulfonamide-chalcones due to the fact of the anterior report, which identified a strong and stable interaction between the chalcone NAT22 (6) and the cTXNPx. In addition, a prediction of the drug-likeness, and the pharmacokinetic profile of all compounds were made, demonstrating a good profile of those chalcones.
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Caleffi GS, Rosa AS, de Souza LG, Avelar JLS, Nascimento SMR, de Almeida VM, Tucci AR, Ferreira VN, da Silva AJM, Santos-Filho OA, Miranda MD, Costa PRR. Aurones: A Promising Scaffold to Inhibit SARS-CoV-2 Replication. JOURNAL OF NATURAL PRODUCTS 2023; 86:1536-1549. [PMID: 37257024 DOI: 10.1021/acs.jnatprod.3c00249] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Aurones are a small subgroup of flavonoids in which the basic C6-C3-C6 skeleton is arranged as (Z)-2-benzylidenebenzofuran-3(2H)-one. These compounds are structural isomers of flavones and flavonols, natural products reported as potent inhibitors of SARS-CoV-2 replication. Herein, we report the design, synthesis, and anti-SARS-CoV-2 activity of a series of 25 aurones bearing different oxygenated groups (OH, OCH3, OCH2OCH3, OCH2O, OCF2H, and OCH2C6H4R) at the A- and/or B-rings using cell-based screening assays. We observed that 12 of the 25 compounds exhibit EC50 < 3 μM (8e, 8h, 8j, 8k, 8l, 8m, 8p, 8q, 8r, 8w, 8x, and 8y), of which five presented EC50 < 1 μM (8h, 8m, 8p, 8q, and 8w) without evident cytotoxic effect in Calu-3 cells. The substitution of the A- and/or B-ring with OCH3, OCH2OCH3, and OCF2H groups seems beneficial for the antiviral activity, while the corresponding phenolic derivatives showed a significant decrease in the anti-SARS-CoV-2 activity. The most potent compound of the series, aurone 8q (EC50 = 0.4 μM, SI = 2441.3), is 2 to 3 times more effective than the polyphenolic flavonoids myricetin (2) and baicalein (1), respectively. Investigation of the five more active compounds as inhibitors of SARS-CoV-2 3CLpro based on molecular dynamic calculations suggested that these aurones should detach from the active site of 3CLpro, and, probably, they could bind to another SARS-CoV-2 protein target (either receptor or enzyme).
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Strauch MA, Tomaz MA, Monteiro-Machado M, Cons BL, Patrão-Neto FC, Teixeira-Cruz JDM, Tavares-Henriques MDS, Nogueira-Souza PD, Gomes SLS, Costa PRR, Schaeffer E, da Silva AJM, Melo PA. Lapachol and synthetic derivatives: in vitro and in vivo activities against Bothrops snake venoms. PLoS One 2019; 14:e0211229. [PMID: 30689661 PMCID: PMC6349327 DOI: 10.1371/journal.pone.0211229] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2018] [Accepted: 01/09/2019] [Indexed: 01/18/2023] Open
Abstract
Background It is known that local tissue injuries incurred by snakebites are quickly instilled causing extensive, irreversible, tissue destruction that may include loss of limb function or even amputation. Such injuries are not completely neutralized by the available antivenins, which in general are focused on halting systemic effects. Therefore it is prudent to investigate the potential antiophidic effects of natural and synthetic compounds, perhaps combining them with serum therapy, to potentially attenuate or eliminate the adverse local and systemic effects of snake venom. This study assessed a group of quinones that are widely distributed in nature and constitute an important class of natural products that exhibit a range of biological activities. Of these quinones, lapachol is one of the most important compounds, having been first isolated in 1882 from the bark of Tabebuia avellanedae. Methodology/Principal findings It was investigated the ability of lapachol and some new potential active analogues based on the 2-hydroxi-naphthoquinone scaffold to antagonize important activities of Bothrops venoms (Bothrops atrox and Bothrops jararaca) under different experimental protocols in vitro and in vivo. The bioassays used to test the compounds were: procoagulant, phospholipase A2, collagenase and proteolytic activities in vitro, venom-induced hemorrhage, edematogenic, and myotoxic effects in mice. Proteolytic and collagenase activities of Bothrops atrox venom were shown to be inhibited by lapachol and its analogues 3a, 3b, 3c, 3e. The inhibition of these enzymatic activities might help to explain the effects of the analogue 3a in vivo, which decreased skin hemorrhage induced by Bothrops venom. Lapachol and the synthetic analogues 3a and 3b did not inhibit the myotoxic activity induced by Bothrops atrox venom. The negative protective effect of these compounds against the myotoxicity can be partially explained by their lack of ability to effectively inhibit phospholipase A2 venom activity. Bothrops atrox venom also induced edema, which was significantly reduced by the analogue 3a. Conclusions This research using a natural quinone and some related synthetic quinone compounds has shown that they exhibit antivenom activity; especially the compound 3a. The data from 3a showed a decrease in inflammatory venom effects, presumably those that are metalloproteinase-derived. Its ability to counteract such snake venom activities contributes to the search for improving the management of venomous snakebites.
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Faiões VDS, da Frota LCRM, Cunha-Junior EF, Barcellos JCF, Da Silva T, Netto CD, Da-Silva SAG, da Silva AJM, Costa PRR, Torres-Santos EC. Second-generation pterocarpanquinones: synthesis and antileishmanial activity. J Venom Anim Toxins Incl Trop Dis 2018; 24:35. [PMID: 30519257 PMCID: PMC6263544 DOI: 10.1186/s40409-018-0174-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2018] [Accepted: 11/07/2018] [Indexed: 11/26/2022] Open
Abstract
Background Despite the development of new therapies for leishmaniasis, among the 200 countries or territories reporting to the WHO, 87 were identified as endemic for Tegumentary Leishmaniasis and 75 as endemic for Visceral Leishmaniasis. The identification of antileishmanial drug candidates is essential to fill the drug discovery pipeline for leishmaniasis. In the hit molecule LQB-118 selected, the first generation of pterocarpanquinones was effective and safe against experimental visceral and cutaneous leishmaniasis via oral delivery. In this paper, we report the synthesis and antileishmanial activity of the second generation of pterocarpanoquinones. Methods The second generation of pterocarpanquinones 2a-f was prepared through a palladium-catalyzed oxyarylation of dihydronaphtalen and chromens with iodolawsone, easily prepared by iodination of lawsone. The spectrum of antileishmanial activity was evaluated in promastigotes and intracellular amastigotes of L. amazonensis, L. braziliensis, and L. infantum. Toxicity was assessed in peritoneal macrophages and selective index calculated by CC50/IC50. Oxidative stress was measured by intracellular ROS levels and mitochondrial membrane potential in treated cells. Results In this work, we answered two pertinent questions about the structure of the first-generation pterocarpanquinones: the configuration and positions of rings B (pyran) and C (furan) and the presence of oxygen in the B ring. When rings B and C are exchanged, we noted an improvement of the activity against promastigotes and amastigotes of L. amazonensis and promastigotes of L. infantum. As to the oxygen in ring B of the new generation, we observed that the oxygenated compound 2b is approximately twice as active against L. braziliensis promastigotes than its deoxy derivative 2a. Another modification that improved the activity was the addition of the methylenedioxy group. A variation in the susceptibility among species was evident in the clinically relevant form of the parasite, the intracellular amastigote. L. amazonensis was the species most susceptible to novel derivatives, whilst L. infantum was resistant to most of them. The pterocarpanoquinones (2b and 2c) that possess the oxygen atom in ring B showed induction of increased ROS production. Conclusions The data presented indicate that the pterocarpanoquinones are promising compounds for the development of new leishmanicidal agents.
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Riça IG, Netto CD, Rennó MN, Abreu PA, Costa PRR, da Silva AJM, Cavalcante MCM. Anti-inflammatory properties of pterocarpanquinone LQB-118 in mice. Bioorg Med Chem 2016; 24:4415-4423. [PMID: 27492193 DOI: 10.1016/j.bmc.2016.07.046] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2016] [Revised: 07/16/2016] [Accepted: 07/20/2016] [Indexed: 11/29/2022]
Abstract
Pterocarpanquinone (+/-)-LQB-118 presents antineoplastic and antiparasitic properties and also shows great inhibitory effect on TNF-α release in vitro. Here, its anti-inflammatory activity was evaluated in a lipopolysaccharide (LPS)-induced lung inflammation model in C57BL/6 mice. LPS inhalation induced a marked neutrophil infiltration to the lungs which was reduced by intraperitoneal treatment with (+/-)-LQB-118 in a similar manner to that of dexamethasone and even better than that of acetylsalicylic acid. Moreover, (+/-)-LQB-118 administration resulted in decrease of NF-κB activation and KC level in lungs, with a pronounced inhibitory effect on TNF-α release, measured in bronchoalveolar lavage fluid. Trying to understand the anti-inflammatory mechanism by which (+/-)-LQB-118 acts, we performed a molecular modeling analysis, including docking to estrogen receptors α and β. Results suggested that (+/-)-LQB-118 may bind to both receptors, with a similar orientation to 17-β-estradiol. Together, these results showed that (+/-)-LQB-118 exhibits an anti-inflammatory effect, most likely by inhibiting TNF-α release and NF-κB activation, which may be related to the estrogen receptor binding.
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Costa L, Pinheiro RO, Dutra PML, Santos RF, Cunha-Júnior EF, Torres-Santos EC, da Silva AJM, Costa PRR, Da-Silva SAG. Pterocarpanquinone LQB-118 induces apoptosis in Leishmania (Viannia) braziliensis and controls lesions in infected hamsters. PLoS One 2014; 9:e109672. [PMID: 25340550 PMCID: PMC4207686 DOI: 10.1371/journal.pone.0109672] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2014] [Accepted: 09/03/2014] [Indexed: 01/02/2023] Open
Abstract
Previous results demonstrate that the hybrid synthetic pterocarpanquinone LQB-118 presents antileishmanial activity against Leishmania amazonensis in a mouse model. The aim of the present study was to use a hamster model to investigate whether LQB-118 presents antileishmanial activity against Leishmania (Viannia) braziliensis, which is the major Leishmania species related to American tegumentary leishmaniasis. The in vitro antileishmanial activity of LQB-118 on L. braziliensis was tested on the promastigote and intracellular amastigote forms. The cell death induced by LQB-118 in the L. braziliensis promastigotes was analyzed using an annexin V-FITC/PI kit, the oxidative stress was evaluated by 2',7'-dichlorodihydrofluorescein diacetate (H2DCFDA) and the ATP content by luminescence. In situ labeling of DNA fragments by terminal deoxyribonucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) was used to investigate apoptosis in the intracellular amastigotes. L. braziliensis-infected hamsters were treated from the seventh day of infection with LQB-118 administered intralesionally (26 µg/kg/day, three times a week) or orally (4,3 mg/kg/day, five times a week) for eight weeks. LQB-118 was active against the L. braziliensis promastigotes and intracellular amastigotes, producing IC50 (50% inhibitory concentration) values of 3,4±0,1 and 7,5±0,8 µM, respectively. LQB-118 induced promastigote phosphatidylserine externalization accompanied by increased reactive oxygen species production and ATP depletion. Intracellular amastigote DNA fragmentation was also observed, without affecting the viability of macrophages. The treatment of L. braziliensis-infected hamsters with LQB-118, either orally or intralesionally, was effective in the control of lesion size, parasite load and increase intradermal reaction to parasite antigen. Taken together, these results show that the antileishmanial effect of LQB-118 extends to L. braziliensis in the hamster model, involves the induction of parasite apoptosis and shows promising therapeutic option by oral or local routes in leishmaniasis.
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Fernandes TDA, Vaz BG, Silva AJMD, Esteves PM, Eberlin MN, Costa PRR. Palladium-catalyzed arylation of enoates with iodobenzene: stereoselective synthesis of trisubstituted olefins. J BRAZIL CHEM SOC 2013. [DOI: 10.1590/s0103-50532013000300018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Fernandes TDA, Vaz BG, Silva AJMD, Esteves PM, Eberlin MN, Costa PRR. Palladium-Catalyzed Arylation of Enoates with Iodobenzene: Stereoselective Synthesis of Trisubstituted Olefins. J BRAZIL CHEM SOC 2013. [DOI: 10.5935/0103-5053.20130067] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
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Fernandes TDA, Gontijo Vaz B, Eberlin MN, da Silva AJM, Costa PRR. Palladium-Catalyzed Tandem Heck-Lactonization from o-Iodophenols and Enoates: Synthesis of Coumarins and the Study of the Mechanism by Electrospray Ionization Mass Spectrometry. J Org Chem 2010; 75:7085-91. [DOI: 10.1021/jo1010922] [Citation(s) in RCA: 45] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Salustiano EJS, Netto CD, Fernandes RF, da Silva AJM, Bacelar TS, Castro CP, Buarque CD, Maia RC, Rumjanek VM, Costa PRR. Comparison of the cytotoxic effect of lapachol, α-lapachone and pentacyclic 1,4-naphthoquinones on human leukemic cells. Invest New Drugs 2009; 28:139-44. [DOI: 10.1007/s10637-009-9231-y] [Citation(s) in RCA: 37] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2008] [Accepted: 02/10/2009] [Indexed: 10/21/2022]
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Frota LCRMD, Canavez RCP, Gomes SLDS, Costa PRR, Silva AJMD. Iodination of phenols in water using easy to handle amine-iodine complexes. J BRAZIL CHEM SOC 2009. [DOI: 10.1590/s0103-50532009001000021] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
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Kaushik-Basu N, Bopda-Waffo A, Talele TT, Basu A, Costa PRR, da Silva AJM, Sarafianos SG, Noël F. Identification and characterization of coumestans as novel HCV NS5B polymerase inhibitors. Nucleic Acids Res 2008; 36:1482-96. [PMID: 18203743 PMCID: PMC2275130 DOI: 10.1093/nar/gkm1178] [Citation(s) in RCA: 73] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2007] [Revised: 12/22/2007] [Accepted: 12/26/2007] [Indexed: 12/31/2022] Open
Abstract
The hepatitis C virus (HCV) NS5B is essential for viral RNA replication and is therefore a prime target for development of HCV replication inhibitors. Here, we report the identification of a new class of HCV NS5B inhibitors belonging to the coumestan family of phytoestrogens. Based on the in vitro NS5B RNA-dependent RNA polymerase (RdRp) inhibition in the low micromolar range by wedelolactone, a naturally occurring coumestan, we evaluated the anti-NS5B activity of four synthetic coumestan analogues bearing different patterns of substitutions in their A and D rings, and observed a good structure-activity correlation. Kinetic characterization of coumestans revealed a noncompetitive mode of inhibition with respect to nucleoside triphosphate (rNTP) substrate and a mixed mode of inhibition towards the nucleic acid template, with a major competitive component. The modified order of addition experiments with coumestans and nucleic acid substrates affected the potencies of the coumestan inhibitors. Coumestan interference at the step of NS5B-RNA binary complex formation was confirmed by cross-linking experiments. Molecular docking of coumestans within the allosteric site of NS5B yielded significant correlation between their calculated binding energies and IC(50) values. Coumestans thus add to the diversifying pool of anti-NS5B agents and provide a novel scaffold for structural refinement and development of potent NS5B inhibitors.
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Pôças ESC, Touza NA, da Silva AJM, Costa PRR, Noël F. Synergistic interaction between ouabain and 8-methoxy-3,9-dihydroxy coumestan, a non-steroidal synthetic inhibitor of Na+,K+-ATPase. Life Sci 2007; 81:1199-204. [PMID: 17884104 DOI: 10.1016/j.lfs.2007.08.021] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2007] [Revised: 07/13/2007] [Accepted: 08/17/2007] [Indexed: 11/16/2022]
Abstract
The use of combination drugs is very common in therapeutics as in the treatment of infectious diseases, cancer and heart failure but controversies about analysis of these interactions are frequent. The aim of the present work was to characterize the interaction between ouabain and 8-methoxy-3,9-dihydroxy coumestan (LQB93), a non-steroidal synthetic inhibitor of Na+,K+-ATPase, as well as the interaction between ouabain and ouabagenin, two cardiac glycosides sharing the same binding site. Inhibition of rat kidney Na+,K+-ATPase with increasing concentrations of the drugs alone or of mixtures of ouabain:ouabagenin and LQB93:ouabain in a fixed 1:4 ratio was performed. In other experiments, increasing concentrations of LQB93 (or ouabain) in the presence of a fixed concentration of ouabain (or ouabagenin) were used for determining the concentration pairs eliciting 50% inhibition in order to construct isobolograms. The mixture (experimental) curve for the ouabain:ouabagenin combination was superimposed on the additive (theoretical) curve indicating additivity, in accordance with the isobolographic analysis. On the other hand, the empirical curve for LQB93:ouabain (IC50=10.6 microM) was significantly shifted to the left in relation to the theoretical curve (IC50=30.7 microM) indicating synergism, further confirmed by the isobolographic analysis. As a conclusion, we show that the combination of a newly synthesized non-steroidal inhibitor and ouabain have a synergistic effect on Na+,K+-ATPase, further supporting a mechanism of inhibition different from ouabain. Present data also support the use of both the isobolograms and combination curves for the assessment of drug interactions occurring at the same molecular target, a situation poorly investigated.
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Pôças ESC, Lopes DVS, da Silva AJM, Pimenta PHC, Leitão FB, Netto CD, Buarque CD, Brito FV, Costa PRR, Noël F. Structure-activity relationship of wedelolactone analogues: structural requirements for inhibition of Na+, K+ -ATPase and binding to the central benzodiazepine receptor. Bioorg Med Chem 2006; 14:7962-6. [PMID: 16945543 DOI: 10.1016/j.bmc.2006.07.053] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2006] [Revised: 07/04/2006] [Accepted: 07/26/2006] [Indexed: 11/18/2022]
Abstract
Coumestans 2a-i, bearing different patterns of substitution in A- and D-rings, were synthesized and evaluated as inhibitors of kidney Na+, K+ -ATPase and ligands for the central benzodiazepine (BZP) receptor. The presence of a hydroxyl group in position 2 favours the effect on Na+, K+ -ATPase but decreases the affinity for the BZP receptor, allowing the design of more selective molecules than the natural wedelolactone. On the other hand, the presence of a catechol in ring D is important for the effect on both molecular targets.
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Lopes DVS, Caruso RRB, Castro NG, Costa PRR, da Silva AJM, Noël F. Characterization of a new synthetic isoflavonoid with inverse agonist activity at the central benzodiazepine receptor. Eur J Pharmacol 2005; 495:87-96. [PMID: 15249156 DOI: 10.1016/j.ejphar.2004.05.026] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2004] [Revised: 05/10/2004] [Accepted: 05/14/2004] [Indexed: 11/28/2022]
Abstract
Research aimed at developing selective drugs acting on gamma-aminobutyric acid (GABA)A receptors introduced compounds from diverse chemical classes unrelated to the 1,4-benzodiazepines, including flavonoids. These studies also revealed the potential use of inverse agonists as cognition-enhancing agents. Here we report pharmacological properties of the novel synthetic isoflavonoid 2-methoxy-3,8,9-trihydroxy coumestan (PCALC36). PCALC36 displaced [3H]flunitrazepam binding to rat brain synaptosomes with an IC50 of 13.8 microM. Scatchard analysis of the effect of PCALC36 showed a concentration-dependent reduction of the Bmax of [3H]flunitrazepam, without a marked change in Kd. This effect could be reversed by diluting and washing the preparation. Addition of 20-microM GABA shifted to the right the inhibition curve of PCALC36 on [3H]flunitrazepam binding (IC50 ratio of 0.68), which is characteristic for inverse agonists. PCALC36 produced little change in the GABAergic tonic currents recorded by whole-cell patch clamp in cultured rat hippocampal neurones, but it caused a 20% reduction in miniature inhibitory postsynaptic current amplitude and completely antagonised the full (direct) agonist midazolam in a quickly reversible manner. The data suggest that the coumestan backbone can be useful for developing novel ligands at the GABAA receptor.
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Silva AJMD, Netto CD, Costa PRR. The first synthesis of (±)-3,4-dihydroxy-8,9-methylenedioxypterocarpan, an antitumoral agent and its coumestan derivative. J BRAZIL CHEM SOC 2004. [DOI: 10.1590/s0103-50532004000600029] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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da Silva AJM, Coelho AL, Simas ABC, Moraes RAM, Pinheiro DA, Fernandes FFA, Arruda EZ, Costa PRR, Melo PA. Synthesis and pharmacological evaluation of prenylated and benzylated pterocarpans against snake venom. Bioorg Med Chem Lett 2004; 14:431-5. [PMID: 14698175 DOI: 10.1016/j.bmcl.2003.10.044] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
Abstract
Edunol (3), a pterocarpan isolated from Harpalyce brasiliana, a plant used in the northeast of Brazil against snakebites, was obtained by synthesis and showed antimyotoxic, antiproteolytic and PLA2 inhibitor properties. These proprieties could be improved through the synthesis of a bioisoster (5), where the prenyl group was replaced by the benzyl group.
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da Silva AJM, Buarque CD, Brito FV, Aurelian L, Macedo LF, Malkas LH, Hickey RJ, Lopes DVS, Noël F, Murakami YLB, Silva NMV, Melo PA, Caruso RRB, Castro NG, Costa PRR. Synthesis and preliminary pharmacological evaluation of new (+/-) 1,4-naphthoquinones structurally related to lapachol. Bioorg Med Chem 2002; 10:2731-8. [PMID: 12057662 DOI: 10.1016/s0968-0896(02)00100-1] [Citation(s) in RCA: 69] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Seven new 1,4-naphthoquinones structurally related to lapachol were synthesized from lawsone and oxygenated arylmercurials. These compounds can also be seen as pterocarpan derivatives where the A-ring was substituted by the 1,4-naphthoquinone nucleus. Pharmacological screening provided evidence of significant biological activities, including effects against proliferation of the MCF-7 human breast cancer cell line, against Herpes Simplex Virus type 2 infection, and against snake poison-induced myotoxicity. One derivative displaced flunitrazepam binding and showed benzodiazepine-like activity, suggesting novel neuroactive structural motifs.
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Amorim MBD, Silva AJMD, Costa PRR. The reaction of safrole derivatives with aluminum chloride: improved procedures for the preparation of catechols or their mono-O-Methylated Derivatives and a mechanistic interpretation. J BRAZIL CHEM SOC 2001. [DOI: 10.1590/s0103-50532001000300005] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
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Chauder BA, Lopes CC, Lopes RSC, da Silva AJM, Snieckus V. Phenylboronic Acid-Mediated Synthesis of 2H-Chromenes. SYNTHESIS-STUTTGART 1998. [DOI: 10.1055/s-1998-2042] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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Costa PRR, Silva AJMD, Vasconcellos MLAA, Lopes CC, Lopes RSC. Variable Chemo-selective Electrophilic Attack on Silylated Aromatic Aldehydes. Synlett 1996. [DOI: 10.1055/s-1996-5530] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/16/2022]
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