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Leishmaniasis is a disease caused by protozoa Leishmania spp., considered as a significant and urgent public health problem mainly in developing countries. In the absence of an effective vaccine, the treatment of infected people is one of the most commonly prophylactic measures used to control this disease. However, the therapeutic arsenal is reduced to a few drugs, with serious side effects and variability in efficacy. Attempting to this problem, in this work, a series of benzothiazole derivatives was synthetized and assayed against promastigotes and intracellular amastigotes of L. amazonensis, as well as the toxicity on macrophages. In addition, studies about the mechanism of action were also performed. Among the synthesized molecules, the substitution at position 4 of the aromatic ring appears to be critical for activity. The best compound exhibited IC50 values of 28.86 and 7.70 µM, against promastigotes and amastigotes of L. amazonensis, respectively, being more active than miltefosine, used as reference drug. The in silico analysis of physicochemical and pharmacokinetic (ADMET) properties of this compound suggested a good profile of oral bioavailability and safety. In conclusion, the strategy of using benzothiazole nucleous in the search for new antileishmanial agents was advantageous and preliminar data provide information about the mechanism of action as well as in silico parameters suggest a good profile for preclinical studies.
Assuntos
Antiprotozoários , Benzotiazóis , Hidrazonas , Leishmania , Benzotiazóis/química , Benzotiazóis/farmacologia , Benzotiazóis/síntese química , Antiprotozoários/farmacologia , Antiprotozoários/química , Antiprotozoários/síntese química , Animais , Hidrazonas/química , Hidrazonas/farmacologia , Hidrazonas/síntese química , Camundongos , Leishmania/efeitos dos fármacos , Macrófagos/efeitos dos fármacos , Macrófagos/parasitologia , Relação Estrutura-Atividade , HumanosRESUMO
Asthma is a disease characterized by chronic inflammation and hyper responsiveness of airways. We aimed to assess the relaxant potential of phosphodiesterase-4 (PDE4) inhibitors N-sulfonilhidrazonic derivatives on non-asthmatic and asthmatic guinea pig trachea. Firstly, guinea pigs were sensitized and challenged with ovalbumin, and then morphological, and contractile changes were evaluated resulting from asthma, followed by evaluation of relaxant effect of derivatives on guinea pig trachea and the cAMP levels measurement by ELISA. It has been evidenced hypertrophy of airway smooth muscle, inflammatory infiltrate, and vascular abnormalities. Moreover, only sensitized tracheal rings were responsive to OVA. Contractile response to histamine, but not to carbachol, was greater in sensitized animals, however the relaxant response to aminophylline and isoprenaline were the same in non-asthmatics and asthmatics. N-sulfonilhidrazonic derivatives presented equipotent relaxant action independent of epithelium, with exception of LASSBio-1850 that presented a low efficacy (< 50%) and LASSBio-1847 with a 4-fold higher potency on asthmatics. LASSBio-1847 relaxant curve was impaired in the presence of propranolol and potentiated by isoprenaline in both groups. Furthermore, relaxation was potentiated 54- and 4-fold by forskolin in non-asthmatics and asthmatics, respectively. Likewise, LASSBio-1847 potentiated relaxant curve of aminophylline 147- and 4-fold in both groups. The PKA inhibitor H-89 impaired the relaxant potency of the derivative. Finally, LASSBio-1847 increased tracheal intracellular cAMP levels similarly to rolipram, selective PDE4 inhibitor, in both animals. LASSBio-1847 showed to be promising to relax guinea pig trachea from non-sensitized and sensitized guinea pigs by activation of ß2-adrenergic receptors/AC/cAMP pathway.
Assuntos
Asma , Broncodilatadores , AMP Cíclico , Modelos Animais de Doenças , Inibidores da Fosfodiesterase 4 , Traqueia , Animais , Cobaias , Inibidores da Fosfodiesterase 4/farmacologia , Asma/tratamento farmacológico , Asma/fisiopatologia , Traqueia/efeitos dos fármacos , Masculino , Broncodilatadores/farmacologia , AMP Cíclico/metabolismo , Músculo Liso/efeitos dos fármacos , Ovalbumina , Relaxamento Muscular/efeitos dos fármacos , Aminofilina/farmacologiaRESUMO
Searching for new alternatives for treating leishmaniasis, we present the synthesis, characterization, and biological evaluation against Leishmania amazonensis of the new ZnCl2(H3)2 complex. H3 is 22-hydrazone-imidazoline-2-yl-chol-5-ene-3ß-ol, a well-known bioactive molecule functioning as a sterol Δ24-sterol methyl transferase (24-SMT) inhibitor. The ZnCl2(H3)2 complex was characterized by infrared, UV-vis, molar conductance measurements, elemental analysis, mass spectrometry, and NMR experiments. The biological results showed that the free ligand H3 and ZnCl2(H3)2 significantly inhibited the growth of promastigotes and intracellular amastigotes. The IC50 values found for H3 and ZnCl2(H3)2 were 5.2 µM and 2.5 µM for promastigotes, and 543 nM and 32 nM for intracellular amastigotes, respectively. Thus, the ZnCl2(H3)2 complex proved to be seventeen times more potent than the free ligand H3 against the intracellular amastigote, the clinically relevant stage. Furthermore, cytotoxicity assays and determination of selectivity index (SI) revealed that ZnCl2(H3)2 (CC50 = 5 µΜ, SI = 156) is more selective than H3 (CC50 = 10 µΜ, SI = 20). Furthermore, as H3 is a specific inhibitor of the 24-SMT, free sterol analysis was performed. The results showed that H3 was not only able to induce depletion of endogenous parasite sterols (episterol and 5-dehydroepisterol) and their replacement by 24-desalkyl sterols (cholesta-5,7,24-trien-3ß-ol and cholesta-7,24-dien-3ß-ol) but also its zinc derivative resulting in a loss of cell viability. Using electron microscopy, studies on the fine ultrastructure of the parasites showed significant differences between the control cells and parasites treated with H3 and ZnCl2(H3)2. The inhibitors induced membrane wrinkle, mitochondrial injury, and abnormal chromatin condensation changes that are more intense in the cells treated with ZnCl2(H3)2.
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A series of resveratrol/hydrazone hybrids were obtained and elucidated by spectroscopic analysis. All compounds were evaluated against colorectal cancer cells (SW480 and Sw620) and nonmalignant cell lines (HaCaT and CHO-K1) to establish the selectivity index. Among the hybrids evaluated, compounds 6e and 7 displayed the highest cytotoxic activity with IC50 values of = 6.5 ± 1.9 µM and 19.0 ± 1.4 µM, respectively, on SW480 cells. In addition, hybrid 7 also exhibited activity on SW620 cells with an IC50 value of 38.41 ± 3.3 µM. Both compounds were even more toxic against these malignant cells in comparison to the nonmalignant ones, as evidenced by higher selectivity indices 48 h after treatment. These compounds displayed better activity and selectivity than parental compounds (PIH and Resveratrol) and the reference drug (5-FU). In addition, it was observed that both compounds caused antiproliferative activity probably exerted by cell cycle arrest at the G2/M or G0/G1 phases, with the formation of cells in the subG0/G1 phase. Furthermore, it was noticed that compound 7 induced mitochondrial depolarization in SW480 cells and positive staining for propidium iodide in both cancer cell lines, suggesting cell membrane damage involving either apoptosis or other processes of death.
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Curcumin and its analogues exhibited anti-inflammatory activity in different experimental models. Recently, we synthesized (2E,3E)-3-buten-2-one-4-(4-hydroxy-3-methoxyphenyl)-2-(4-(4-methoxyphenyl)-2-thiazolyl)hydrazone (RI75), a curcumin analogue with a thiazolyl hydrazone moiety. In the present study, we investigated the effects induced by RI75 in different models of inflammation and pain in mice, as well as some underlying mechanisms. Pre-treatment with RI75 (40 mg/kg, intraperitoneal; i.p.) or curcumin (40 mg/kg, i.p.) reduced the mechanical allodynia and paw edema induced by intraplantar (i.pl) injection of carrageenan. RI75 antiallodynic activity was reduced by pre-treatment with naltrexone (5 and 10 mg/kg, i.p.) and cyproheptadine (10 mg/kg, i.p.), but not glibenclamide (20 and 40 mg/kg, i.p.). In a model of neuropathic pain, a single i.p. administration of RI75 (40 mg/kg) or curcumin (40 mg/kg) attenuated the ongoing mechanical allodynia induced by repeated administrations of paclitaxel. Pre-treatment with RI75 (40 mg/kg, i.p.) or curcumin (40 mg/kg, i.p.) also reduced tumor necrosis factor-α and interleukin-6 production and myeloperoxidase activity induced by carrageenan. The results of the present study demonstrate that RI75, a synthetic curcumin analogue, exhibits antiallodynic and antiedematogenic activities. Activation of opioidergic and serotonergic mechanisms and reduced production of inflammatory mediators and neutrophil recruitment may underlie RI75 activities.
Assuntos
Curcumina , Hiperalgesia , Interleucina-6 , Neuralgia , Fator de Necrose Tumoral alfa , Animais , Curcumina/análogos & derivados , Curcumina/farmacologia , Modelos Animais de Doenças , Edema/tratamento farmacológico , Edema/metabolismo , Hiperalgesia/tratamento farmacológico , Hiperalgesia/metabolismo , Inflamação/induzido quimicamente , Interleucina-6/antagonistas & inibidores , Interleucina-6/biossíntese , Camundongos , Neuralgia/tratamento farmacológico , Neuralgia/metabolismo , Fator de Necrose Tumoral alfa/antagonistas & inibidores , Fator de Necrose Tumoral alfa/biossínteseRESUMO
BACKGROUND: Leishmaniasis is a worldwide health problem, highly endemic in developing countries. Among the four main clinical forms of the disease, visceral leishmaniasis is the most severe, fatal in 95% of cases. The undesired side-effects from first-line chemotherapy and the reported drug resistance search for effective drugs that can replace or supplement those currently used in an urgent need. Aminoguanidine hydrazones (AGH's) have been explored for exhibiting a diverse spectrum of biological activities, in particular the antileishmanial activity of MGBG. The bioisosteres thiosemicarbazones (TSC's) offer a similar biological activity diversity, including antiprotozoal effects against Leishmania species and Trypanosoma cruzi. OBJECTIVES: Considering the impact of leishmaniasis worldwide, this work aimed to design, synthesize, and perform a screening upon L. chagasi amastigotes and for the cytotoxicity of the small "inhouse" library of both AGH and TSC derivatives and their structurally-related compounds. METHODS: A set of AGH's (3-7), TSC's (9, 10), and semicarbazones (11) were initially synthesized. Subsequently, different semi-constrained analogs were designed and also prepared, including thiazolidines (12), dihydrothiazines (13), imidazolines (15), pyrimidines (16, 18) azines (19, 20), and benzotriazepinones (23-25). All intermediates and target compounds were obtained with satisfactory yields and exhibited spectral data consistent with their structures. All final compounds were evaluated against L. chagasi amastigotes and J774.A1 cell line. Molecular docking was performed towards trypanothione reductase using GOLD® software. RESULTS: The AGH's 3i, 4a, and 5d, and the TSC's 9i, 9k, and 9o were selected as valuable hits. These compounds presented antileishmanial activity compared with pentamidine, showing IC50 values ranged from 0.6 to 7.27 µM, maximal effects up to 55.3%, and satisfactory SI values (ranged from 11 to 87). On the other hand, most of the resulting semi-constrained analogs were found cytotoxic or presented reduced antileishmanial activity. In general, TSC class is more promising than its isosteric AGH analogs, and the beneficial aromatic substituent effects are not similar in both series. In silico studies have suggested that these hits are capable of inhibiting the trypanothione reductase from the amastigote forms. CONCLUSION: The promising antileishmanial activity of three AGH's and three TSC's was characterized. These compounds presented antileishmanial activity compared with PTD, showing IC50 values ranged from 0.6 to 7.27 µM, and satisfactory SI values. Further pharmacological assays involving other Leishmania strains are in progress, which will help choose the best hits for in vivo experiments.
Assuntos
Leishmania infantum , Tiossemicarbazonas , Guanidinas , Hidrazonas/farmacologia , Simulação de Acoplamento Molecular , Relação Estrutura-Atividade , Tiossemicarbazonas/farmacologiaRESUMO
The title mol-ecular structure, namely, di-aqua-tris-(µ3-1,3-bis-{[1-(2-oxidophen-yl)ethyl-idene]amino}-propan-2-olato)-µ3-hydroxido-dinitrato-hexa-copper(II) ethanol tris-olvate, [Cu6(C19H19N2O3)3(NO3)2(OH)(H2O)2]·3C2H5OH, corres-ponds to a non-symmetric hexa-nuclear copper complex. The complex exhibits one core in which three CuII metal centres are mutually inter-connected, two by two, via three phenolato oxygen anions acting in a µ2-mode. These three copper cations are inter-connected in a µ3-mode by one hydroxyl group. An open-cube structure is generated in which each of the CuII cations of the three CuO4N units is connected by two µ2-O anions from phenolate groups and one µ3-O atom from a hy-droxy anion. Each of the three penta-coordinated CuII cations situated in the open-cube unit has a distorted NO4 square-pyramidal environment. Each of these three CuII centres is inter-connected with another CuII cation via one enolate O atom in µ2-mode, yielding one CuNO4 unit and two CuNO3 units. The penta-coordinated CuII atom has a distorted square-pyramidal environment while the two tetra-coordinated copper(II) cations are situated in a square-planar environment. A series of intra-molecular O-Hâ¯O hydrogen bonds are observed. In the crystal, the units are connected two by two by inter-molecular C-Hâ¯O and O-Hâ¯O hydrogen bonds, thus forming sheets parallel to the ac plane.
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SUMMARY Introduction: Leishmaniasis is a disease caused by protozoa of the genus Leishmania and is considered endemic in 98 countries. Treatment with pentavalent antimonials has a high toxicity, which motivates the search for effective and less toxic drugs. α- and β-lapachones have shown different biological activities, including antiprotozoa. In recent studies, the isonicotinoylhydrazone and phthalazinylhydrazone groups were considered innovative in the development of antileishmania drugs. Molecular hybridization is a strategy for the rational development of new prototypes, where the main compound is produced through the appropriate binding of pharmacophoric subunits. Aims: To synthesize four hybrids of α- and β-lapachones, together with the isonicotinoylhydrazone and phthalazinylhydrazone groups and to determine the antileishmania activity against the promastigotic forms of L. amazonensis, L. infantum and L. major. Results: β-lapachone derivatives were more active against all tested leishmania species. βACIL (IC50 0.044μM) and βHDZ (IC50 0.023μM) showed 15-fold higher activity than amphotericin B. The high selectivity index exhibited by the compounds indicates greater safety for vertebrate host cells. Conclusion: The results of this work show that the hybrids βACIL and (3HDZ are promising molecules for the development of new antileishmania drugs.
RESUMEN Introducción: Leishmaniasis es una enfermedad causada por protozoos del género Leishmania y se considera endémica en 98 países. El tratamiento con antimoniales pentavalentes tiene una alta toxicidad, lo que motiva la búsqueda de fármacos eficaces y menos tóxico. α- y β-lapachones han mostrado diferentes actividades biológicas, incluido los antiprotozoarios. En estudios recientes, los grupos isonicotinoilhidra-zona y ftalazinilhidrazona se consideraron innovadores en el desarrollo de fármacos antileishmania. La hibridación molecular es una estrategia para el desarrollo racional de nuevos prototipos, donde el compuesto principal se produce a través de la unión apropiada de subunidades farmacofóricas. Objetivos: Sintetizar cuatro híbridos de α- y β-lapachones, junto con los grupos isonicotinoilhidrazona y ftalazinilhidrazona y determinar la actividad antileishmania frente a las formas promastigotas de L. amazonensis, L. infantum y L. major. Resultados: Los derivados de β-lapachone fueron más activos contra todas las especies de leishmania probadas. La βACIL (CI50 0,044μM) y βHDZ (CI50 0,023μM) mostraron actividad 15 veces mayor que la anfotericina B. El alto índice de selectividad que presentan los compuestos indica una mayor seguridad para las células huésped del vertebrado. Conclusión: Los resultados de este trabajo demuestran que los híbridos (ACIL y (HDZ son moléculas prometodoras para el desarrollo de nuevos fármacos antileishmania.
RESUMO Introdução: A leishmaniose é uma doença causada por protozoários do género Leishmania e é considerada endémica em 98 países. O tratamento com antimoniais pentavalentes apresenta alta toxicidade, o que motiva a pesquisa por medicamentos eficazes e menos tóxicos. α- e β-lapachones tém mostrado diferentes atividades biológicas, incluindo antiprotozoários. Em estudos recentes, os grupos isonicotinoilhi-drazona e ftalazinilhidrazona foram considerados inovadores no desenvolvimento de drogas antileishmania. A hibridização molecular é uma estratégia para o desenvolvimento racional de novos protótipos, onde o composto principal é produzido através da ligação apropriada de subunidades farmacofóricas. Objetivos: Sintetizar quatro híbridos de α- e β-lapachones, juntamente com os grupos isonicotinoil-hidra-zona e ftalazinilhidrazona e determinar a atividade antileishmania contra as formas promastigóticas de L. amazonensis, L. infantum e L. major. Resultados: Os derivados de β-lapachona foram mais ativos contra todas as espécies de leishmania testadas. BACIL (IC50 0,044 μM) e βHDZ (IC50 0,023 μM) apresentaram atividade 15 vezes maior do que a anfotericina B. O alto índice de seletividade dos compostos indica maior segurança para células hospedeiras de vertebrados. Conclusaõ: Os resultados deste trabalho mostram que os híbridos βACIL e βHDZ são moléculas promissoras para o desenvolvimento de novos fármacos antileishmania.
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This paper reports on the synthesis and characterization of two new polypyridyl-hydrazone Schiff bases, (E)-N'-(6-oxo-1,10-phenanthrolin-5(6H)-ylidene)thiophene-2-carbohydrazide (L1) and (E)-N'-(6-oxo-1,10-phenanthrolin-5(6H)-ylidene)furan-2-carbohydrazide (L2), and their two Ru(II) complexes of the general formula [RuCl(DMSO)(phen)(Ln)](PF6). Considering that hydrazides are a structural part of severa l drugs and metal complexes containing phenanthroline derivatives are known to interact with DNA and to exhibit antitumor activity, more potent anticancer agents can be obtained by covalently linking the thiophene acid hydrazide or the furoic acid hydrazide to a 1,10-phenanthroline moiety. These ligands and the Ru(II) complexes were characterized by elemental analyses, electronic, vibrational, 1H NMR, and ESI-MS spectroscopies. Ru is bound to two different N-heterocyclic ligands. One chloride and one S-bonded DMSO in cis-configuration to each other complete the octahedral coordination sphere around the metal ion. The ligands are very effective in inhibiting cellular growth in a chronic myelogenous leukemia cell line, K562. Both complexes are able to interact with DNA and present moderate cytotoxic activity, but 5 min of UV-light exposure increases cytotoxicity by three times.
Assuntos
Complexos de Coordenação/farmacologia , Hidrazonas/farmacologia , Luz , Fenantrolinas/farmacologia , Rutênio/farmacologia , Animais , Bovinos , Morte Celular/efeitos dos fármacos , Complexos de Coordenação/síntese química , Complexos de Coordenação/química , DNA/metabolismo , Dimetil Sulfóxido/química , Humanos , Hidrazonas/síntese química , Hidrazonas/química , Células K562 , Ligantes , Fenantrolinas/síntese química , Fenantrolinas/química , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização por ElectrosprayRESUMO
Toxicity and poor adherence to treatment that favors the generation of resistance in the Leishmania parasites highlight the need to develop better alternatives. Here, we evaluated the in vitro effectiveness of hydrazone derived from chromanes 2-(2,3-dihydro-4H-1-benzothiopyran-4-ylidene) hydrazide (TC1) and 2-(2,3-dihydro-4H-1-benzopyran-4-ylidene) hydrazide (TC2) and the mixture of triterpene saponin hederagenin-3-O-(3,4-O-diacetyl-ß-D-xylopyranosyl-(1à3)-a-L- rhamnopyranosyl-(1à2)-a-L-arabinofuranoside, hederagenin-3-O-(3,4-O-diacetyl-a-L- arabinopyranosyl-(1à3)-a-L-rhamnopyranosyl-(1à2)-a-L-arabinofuranoside and, hederagenin-3-O-(4-O-acetyl-ß-D-xylopyranosyl-(1à3)-a-L-rhamnopyranosyl-(1à2)-a-L-arabinofuranoside from Sapindus saponaria (SS) on L. braziliensis and L. pifanoi. Mixtures of TC1 or TC2 with saponin were formulated for topical application and the therapeutic effectiveness was evaluated in the model for cutaneous leishmaniasis (CL) in golden hamster. The mode of action of these compounds was tested on various parasite processes and ultrastructural parasite modifications. TC1, TC2 and SS showed moderate cytotoxicity when tested independently but toxicity was improved when tested in combination. The compounds were more active against intracellular Leishmania amastigotes. In vivo studies showed that combinations of TC1 or TC2 with SS in 1:1 ratio (w/w) cured 100% of hamsters with no signs associated with toxicity. The compounds did cause changes in the mitochondrial activity of the parasite with a decrease in ATP levels and depolarization of membrane potential and overproduction of reactive oxygen species; nevertheless, these effects were not related to alterations in membrane permeability. The phagolysosome ultrastructure was also affected impacting the survival of Leishmania but the function of the lysosome nor the pH inside the phagolysosome did not change. Lastly, there was a protease inhibition which was directly related to the decrease in the ability of Leishmania to infect and multiply inside the macrophage. The results suggest that the combination of TC1 and TC2 with SS in a 1:1 ratio is capable of curing CL in hamsters. This effect may be due to the ability of these compounds to affect parasite survival and the ability to infect new cells.
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Hidrazonas/farmacologia , Leishmania/efeitos dos fármacos , Sapindus/química , Saponinas/farmacologia , Trifosfato de Adenosina/metabolismo , Animais , Antiprotozoários/farmacologia , Antiprotozoários/toxicidade , Hidrazonas/química , Hidrazonas/toxicidade , Leishmania/metabolismo , Leishmania/ultraestrutura , Leishmania braziliensis/efeitos dos fármacos , Leishmania braziliensis/metabolismo , Leishmania braziliensis/ultraestrutura , Estágios do Ciclo de Vida/efeitos dos fármacos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/ultraestrutura , Peptídeo Hidrolases/efeitos dos fármacos , Peptídeo Hidrolases/metabolismo , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Extratos Vegetais/toxicidade , Reinfecção , Saponinas/química , Saponinas/toxicidadeRESUMO
Nitrofurans (5-nitro-2-hydrazonylfuran as pharmacophore) are a group of widely used antimicrobial drugs but also associated to a variety of side effects. The molecular mechanisms that underlie the cytotoxic effects of nitrofuran drugs are not yet clearly understood. One-electron reduction of 5-nitro group by host enzymes and ROS production via redox cycling have been attributed as mechanisms of cell toxicity. However, the current evidence suggests that nitrofuran ROS generation by itself is uncapable to explain the whole toxic effects associated to nitrofuran consumption, proposing a nitro-reduction independent mechanism of toxicity. In the present work, a series of nitrated and non-nitrated derivatives of nitrofuran drugs were synthesized and evaluated in vitro for their cytotoxicity, ROS-producing capacity, effect on GSH-S-transferase and antibacterial activity. Our studies showed that in human cells non-nitrated derivatives were less toxic than parental drugs but, unexpectedly preserved the ability to generate intracellular ROS in similar amounts to nitrofurans despite not entering into a redox cycle mechanism. In addition, some non-nitrated derivatives although being uncapable to generate ROS exhibited the highest cell toxicity among all derivatives. Inhibition of cytosolic glutathione-S-transferase activity by some derivatives was also observed. Finally, only nitrofuran derivatives displayed antibacterial effect. Results suggest that the combined 2-hydrazonylfuran moiety, redox cycling of 5-nitrofuran, and inhibitory effects on antioxidant enzymes, would be finally responsible for the toxic effects of the studied nitrofurans on mammalian cells.
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Antibacterianos/toxicidade , Microssomos Hepáticos/efeitos dos fármacos , Microssomos Hepáticos/metabolismo , Nitrofuranos/toxicidade , Espécies Reativas de Oxigênio/metabolismo , Células A549 , Animais , Antibacterianos/química , Células HCT116 , Células HEK293 , Células HL-60 , Células Hep G2 , Humanos , Masculino , Nitrofuranos/química , Oxirredução/efeitos dos fármacos , Ratos , Ratos Sprague-DawleyRESUMO
In this work, we report the antileishmanial activity of 15 compounds based on 2-pyrimidinyl hydrazone and N-acylhydrazone derivatives, being 13 new compounds. All compounds were tested against promastigotes and Leishmania amazonensis-GFP amastigotes, as well as murine macrophages. Besides, studies about the mechanism of action of the best antileishmanial compounds and in silico physicochemical and pharmacokinetic properties were performed. Studies about the mechanism of action of representative compounds of each class showed slight differences in mode of action and both are able to cause mitochondrial depolarization and increase of intracellular ROS levels. Through computational tool and further analysis of the physicochemical and pharmacokinetic parameters, the results indicating good oral bioavailability. These results confirm the potential of 2-pyrimidinyl derivatives as lead compounds in antileishmanial drug discovery.
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Antiprotozoários/farmacologia , Hidrazonas/farmacologia , Leishmania/efeitos dos fármacos , Leishmaniose/tratamento farmacológico , Pirimidinas/farmacologia , Animais , Antiprotozoários/síntese química , Antiprotozoários/química , Relação Dose-Resposta a Droga , Descoberta de Drogas , Hidrazonas/síntese química , Hidrazonas/química , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Estrutura Molecular , Testes de Sensibilidade Parasitária , Pirimidinas/síntese química , Pirimidinas/química , Espécies Reativas de Oxigênio/metabolismo , Relação Estrutura-AtividadeRESUMO
Aim: To evaluate the potential of three benzohydrazones (1-3), four acylhydrazones derived from isoniazid (INH-acylhydrazones) (4-7) and one hydrazone (8) as antituberculosis agents. Materials & methods: Inhibitory and bactericidal activities were determined for the reference Mycobacterium tuberculosis (Mtb) strain and clinical isolates. Cytotoxicity, drug combinations and ethidium bromide accumulation assays were also performed. Results: The tested compounds (1-8) presented excellent antituberculosis activity with surprisingly inhibitory (0.12-250 µg/ml) and bactericidal values, even against multidrug-resistant Mtb clinical isolates. Compounds showed high selectivity index, with values reaching 1833.33, and a limited spectrum of activity. Some of the compounds (2 & 8) are also great inhibitors of bacillus efflux pumps. Conclusion: Benzohydrazones and INH-acylhydrazones may be considered scaffolds for the development of new anti-Mtb drugs.
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Antituberculosos/farmacologia , Hidrazonas/farmacologia , Isoniazida/farmacologia , Mycobacterium tuberculosis/efeitos dos fármacos , Animais , Antituberculosos/síntese química , Antituberculosos/química , Linhagem Celular Tumoral , Chlorocebus aethiops , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Etídio/metabolismo , Células HeLa , Humanos , Hidrazonas/síntese química , Hidrazonas/química , Isoniazida/síntese química , Isoniazida/química , Testes de Sensibilidade Microbiana , Estrutura Molecular , Mycobacterium tuberculosis/isolamento & purificação , Tuberculose/microbiologia , Células VeroRESUMO
Three imidazole hydrazone compounds, namely 2-(4-nitro-1H-imidazol-1-yl)-N'-[1-(pyridin-2-yl)ethylidene]acetohydrazide, C12H12N6O3, (1), 2-(2-nitro-1H-imidazol-1-yl)-N'-[1-(pyridin-2-yl)ethylidene]acetohydrazide, C12H12N6O3, (2), and 2-(2-nitro-1H-imidazol-1-yl)-N'-[(phenyl)(pyridin-2-yl)methylidene]acetohydrazide, C17H14N6O3, (3), were obtained and fully characterized, including their crystal structure determinations. While all the compounds proved not to be cytotoxic to J774.A1 macrophage cells, (1) and (3) exhibited activity against Leishmania chagasi, whereas (2) was revealed to be inactive. Since both (1) and (3) exhibited antileishmanial effects, while (2) was devoid of activity, the presence of the acetyl or benzoyl groups was possibly not a determining factor in the observed antiprotozoal activity. In contrast, since (1) and (3) are 4-nitroimidazole derivatives and (2) is a 2-nitroimidazole-derived compound, the presence of the 4-nitro group probably favours antileishmanial activity over the 2-nitro group. The results suggested that further investigations on compounds (1) and (3) as bioreducible antileishmanial prodrug candidates are called for.
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A new series of 1,4-disubstituted-1,2,3-triazole derivatives were synthesized through the copper-catalyzed azide-alkyne 1,3-dipolar cycloaddition (Click chemistry) and their inhibitory activities were evaluated against different human glioblastoma (GBM) cell lines, including highly drug-resistant human cell lines GBM02, GBM95. The most effective compounds were 9d, containing the methylenoxy moiety linked to triazole and the tosyl-hydrazone group, and the symmetrical bis-triazole 10a, also containing methylenoxy moiety linked to triazole. Single crystal X-ray diffraction analysis was employed for structural elucidation of compound 9d. In silico analyses of physicochemical, pharmacokinetic, and toxicological properties suggest that compounds 8a, 8b, 8c, 9d, and 10a are potential candidates for central nervous system-acting drugs.
Assuntos
Antineoplásicos/farmacologia , Desenho de Fármacos , Glioblastoma/tratamento farmacológico , Triazóis/farmacologia , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Ensaios de Seleção de Medicamentos Antitumorais , Glioblastoma/patologia , Humanos , Estrutura Molecular , Ratos , Relação Estrutura-Atividade , Triazóis/síntese química , Triazóis/química , Células Tumorais CultivadasRESUMO
Abstract A novel molecular system based on 2-((2-(4-chlorophenylhydrazone)methyl)quinoline (1-E ) was synthesized. Interconversion of 1-E to its configurational isomer 1-Z was achieved using UV radiation (250 W Hg lamp). Such isomerization was monitored by ¹H-NMR. The results suggest that the hydrazone derivative can act as a chemical brake in solution. This molecular system was structurally (Single Crystal X-Ray diffraction and DFT calculations) and spectroscopically (NMR, UV, and IR) characterized. Electrochemical measurements showed that configurational changes induce differential redox behavior. In this regard, the reported quinoline system exhibits different dynamic absorption and electrochemical properties that are modulated by UV-light. Therefore, 1-E can be regarded as a potential photo-electrochemical switch.
Resumen Se sintetizó un nuevo sistema molecular basado en 2-((2-(4-chlorofenilhidrazona)metil)quinolina. Del mismo modo, se evaluó la respuesta dinámica de este compuesto a radiación ultravioleta y formación de un enlace de hidrógeno intramolecular. Los resultados muestran que este derivado de hidrazona puede actuar como freno en solución. El sistema en mención es descrito estructural (Cristalografía de Rayos X y cálculos DFT) y espectroscópicamente (RMN, UV e IR). La interconversión de este sistema entre las configuraciones 1-E y 1-Z fue mediada por radiación UV y monitoreada a través de RMN-¹H. El estudio electroquímico mostró un comportamiento diferencial en función de su configuración, aspecto fundamental en el desarrollo de sistemas foto- y electroquímicamente modulados.
Resumo Neste trabalho é apresentado um novo sistema molecular baseado na 2-((2-(4-clorofenilhidrazona)metil)quinolina, capaz de responder dinamicamente à radiação ultravioleta formando uma ligação de hidrogénio intramolecular que atua como um freio na solução. Este sistema é descrito estruturalmente (cristalografia de raios-X e DFT) e por diferentes técnicas espectroscópicas (RMN, de UV e de IV). Radiação UV foi usada para fazer a interconversão da hidrazona 1-E no seu isômero configuracional 1-Z . Este processo foi monitorado pelo RMN. As medidas eletroquímicas mostraram que as mudanças configuracionais entre os isômeros induzem a comportamentos redox diferentes, o que é uma caraterística chave no desenvolvimento de interruptores fotoelectroquímicos.
RESUMO
The discovery and development of novel inhibitors with activity against variants of human immunodeficiency virus type 1 (HIV-1) is pivotal for overcoming treatment failure. As our ongoing work on research of anti-HIV-1 inhibitors, 32 N-arylsulfonyl-3-acylindole benzoyl hydrazone derivatives were prepared by introduction of the hydrazone fragments on the N-arylsulfonyl-3-acylindolyl skeleton and preliminarily screened in vitro as HIV-1 inhibitors for the first time. Among of all the reported analogues, eight compounds exhibited significant anti-HIV-1 activity, especially N-(3-nitro)phenylsulfonyl-3-acetylindole benzoyl hydrazone (18) and N-(3-nitro)phenylsulfonyl-3-acetyl-6-methylindole benzoyl hydrazone (23) displayed the most potent anti-HIV-1 activity with EC50 values of 0.26 and 0.31 µg/mL, and TI values of >769.23 and >645.16, respectively. It is noteworthy that introduction of R3 as the methyl group and R2 as the hydrogen group could result in more potent compounds. This suggested that introduction of R3 as the methyl group could be taken into account for further preparation of these kinds of compounds as anti-HIV-1 agents
Assuntos
Síndrome da Imunodeficiência Adquirida/tratamento farmacológico , HIV-1/classificação , Fármacos Anti-HIV/análise , Inibidores da Fusão de HIVRESUMO
Cutaneous leishmaniasis (CL) is a neglected tropical disease, which causes severe skin lesions. Due to the lack of effective vaccines, and toxicity or reduced effectiveness of available drugs in addition to complex and prolonged treatments, there is an urgent need to develop alternatives for the treatment for CL with different mechanisms of action. In our effort to search for new promising hits against Leishmania parasites we prepared 18 acyl hydrazone derivatives of thiochroman-4-ones. Compounds were evaluated for their in vitro antileishmanial activity against the intracellular amastigote form of Leishmania panamensis and cytotoxic activity against human monocytes (U-937 ATCC CRL-1593.2). Our results show that derivatization of the thiochroman-4-ones with acyl hydrazones significantly enhances the antileishmanial activity. Among the compounds tested semicarbazone and thiosemicarbazone derivatives of thioflavanone 19 and 20 displayed the highest antileishmanial activities, with EC50 values of 5.4 and 5.1 µM and low cytotoxicities (100.2 and 50.1 µM respectively), resulting in higher indexes of selectivity (IS).
Assuntos
Antiprotozoários/farmacologia , Cromanos/farmacologia , Hidrazonas/farmacologia , Morte Celular/efeitos dos fármacos , Flavanonas/química , Flavanonas/farmacologia , Humanos , Leishmania/efeitos dos fármacos , Monócitos/citologia , Monócitos/efeitos dos fármacosRESUMO
Herein, we report the synthesis of a double hydrazone capable of undergoing photochemical E/Z isomerization through the imine double bonds. The bis(hydrazone) 1-E,E can be considered as a "two-arm" system in which the controlled movement of each arm is obtained by photo-modulation, making possible the appearance of two isolable metastable isomeric states 1-E,Z and 1-Z,Z. Such states are characterized by very specific structural, optical, and electrochemical properties. The latter allows the reversible return from either 1-E,Z or 1-Z,Z to the 1-E,E state. Our results are of great importance in the further development of molecular machines and photochemically controlled reactions by introducing for the first time double hydrazones as tunable photochemical switches.
RESUMO
OBJECTIVE: Scopolamine (SCO) administration to rats induces molecular features of AD and other dementias, including impaired cognition, increased oxidative stress, and imbalanced cholinergic transmission. Although mitochondrial dysfunction is involved in different types of dementias, its role in cognitive impairment induced by SCO has not been well elucidated. The aim of this work was to evaluate the in vivo effect of SCO on different brain mitochondrial parameters in rats to explore its neurotoxic mechanisms of action. METHODS: Saline (Control) or SCO (1 mg/kg) was administered intraperitoneally 30 min prior to neurobehavioral and biochemical evaluations. Novel object recognition and Y-maze paradigms were used to evaluate the impact on memory, while redox profiles in different brain regions and the acetylcholinesterase (AChE) activity of the whole brain were assessed to elucidate the amnesic mechanism of SCO. Finally, the effects of SCO on brain mitochondria were evaluated both ex vivo and in vitro, the latter to determine whether SCO could directly interfere with mitochondrial function. RESULTS: SCO administration induced memory deficit, increased oxidative stress, and increased AChE activities in the hippocampus and prefrontal cortex. Isolated brain mitochondria from rats administered with SCO were more vulnerable to mitochondrial swelling, membrane potential dissipation, H2O2 generation and calcium efflux, all likely resulting from oxidative damage. The in vitro mitochondrial assays suggest that SCO did not affect the organelle function directly. CONCLUSION: In conclusion, the present results indicate that SCO induced cognitive dysfunction and oxidative stress may involve brain mitochondrial impairment, an important target for new neuroprotective compounds against AD and other dementias.